Kripke: Identity and Necessity
There's been some interest in Kripke's article Identity and Necessity
There's a PDF at
Identity and necessity, but it's pretty ugly. Someone might like to link to a better version.
This paper predates the book Naming and Necessity, which has been treated elsewhere on this forum. It covers a similar set of ideas, so one of things we might discuss here is how the book differs from the paper.
Kripke, at a very young age, developed a formal semantics for modal logic, presenting a completeness theorem. His work on possible world semantics ushered in a period of rapid and varied growth in that area. The present paper and the subsequent book look to the wider philosophical implications of that work.
The key topic of the paper is 'How are contingent identity statements possible?", or as Kant may have put it, "How are synthetic a priori judgements possible?".
So there's a start. This thread will be focused on this paper, and posters are asked to stay on-topic and engage with the paper and ideas/arguments therein (it is strongly recommended to read the paper, if you're not already familiar with Kripke's work)
There's a PDF at
Identity and necessity, but it's pretty ugly. Someone might like to link to a better version.
This paper predates the book Naming and Necessity, which has been treated elsewhere on this forum. It covers a similar set of ideas, so one of things we might discuss here is how the book differs from the paper.
Kripke, at a very young age, developed a formal semantics for modal logic, presenting a completeness theorem. His work on possible world semantics ushered in a period of rapid and varied growth in that area. The present paper and the subsequent book look to the wider philosophical implications of that work.
The key topic of the paper is 'How are contingent identity statements possible?", or as Kant may have put it, "How are synthetic a priori judgements possible?".
So there's a start. This thread will be focused on this paper, and posters are asked to stay on-topic and engage with the paper and ideas/arguments therein (it is strongly recommended to read the paper, if you're not already familiar with Kripke's work)
Comments (468)
[math]
(1)\,(x)(y) [(x=y) \supset (Fx \supset Fy] \\(2)\,(x) \Box (x=x) \\(3)\,(x)(y) (x=y) \supset [ \Box (x=x) \supset \Box [(x=y)] \\ (4)\,(x)(y) [(x=y) \supset \Box [(x=y)]
[/math]
What's posited here is that if two things are identical then they are necessarily identical.
So what? Well, if it is right - and it seems it is - then in no possible world is Clark Kent not Superman. For we know the Kent is Superman, and we can swapping x for Superman and y for Kent, we show that necessarily Kent is Superman.
But surely it may have turned out that Superman had taken on a different secret identity?
That's the pull of the argument attributed to David Wiggins.
(the maths I used, for those wanting to use Mathjax is
(1)\,(x)(y) [(x=y) \supset (Fx \supset Fy] \\(2)\,(x) \Box (x=x) \\(3)\,(x)(y) (x=y) \supset [ \Box (x=x) \supset \Box [(x=y)] \\ (4)\,(x)(y) [(x=y) \supset \Box [(x=y)]
)
https://thephilosophyforum.com/discussion/4545/naming-and-necessity-reading-group
https://thephilosophyforum.com/discussion/4857/naming-and-necessity-lecture-three/p1
Some thoughts about terminology. Kripke introduces the term de re modality, which I think to newcomers can be confusing. Care to address this @Banno?
Further, on around page 15, Kripke brings up the statement, that the the 37'th president of the United States is non-rigid and Nixon is rigid. This would sound confusing to someone at first. I can attempt answering this on the basis that one doesn't need to invoke their imagination too wildly and simply designate that there could be a possible world where Humphrey won the election, thus it is contingent. However within the reference frame of our world Nixon won the the 37 elections for the president of the United States, making him a rigid designator. It's important to note that the possibility of 37th election of the United States sets up the possibility that out (this is our criteria condition for identity) of two possible candidates one or the other won. So, following from this we can only reference who won based on the feature of the world obeying causality (Kripke relies on a causal theory of reference).
I'm not sure if this is a good place to start, so please let me know @Banno.
Edit:
I would like to reiterate where people go on a wild goose chase, that counterfactuals like Nixon could have lost the binary relation of either winning or losing the presidency or winning it with respect to the causal chain of events in our world, not some other, and hence the status of Nixon being a rigid designator is assigned by our world not any other. That's just one instance where a counterfactual could have arisen given the epistemic criteria that fulfills the condition of him winning or losing the election. Treat everything else as et. cetera.
And, if it needs to be said in the positive that, yes, the causal chain of events would be the framing relation that allows Nixon to obtain as a rigid designator, in our world.
Kant's synthetic a priori judgement is more in agreement with a Kripke necessary identity statement than a contingent identity statement, though Kant's synthetic a priori is more about knowledge by acquaintance than Kripke's knowledge by description.
Contingent identity statements versus Kant's a priori judgements
Kripke writes in the introduction: "How are contingent identity statements possible? This question is phrased by analogy with the way Kant phrased his question How are synthetic a priori judgments possible?. However, he later writes: "To state finally what I think, as opposed to what seems to be the case, or what others think, I think that in both cases, the case of names and the case of the theoretical identifications, the identity statements are necessary and not contingent"
As regards contingent identity statements, such as "Hesperus is Phosphorus", from Hume's principle of constant conjunction, we logically infer that Hesperus is Phosphorus, and therefore is logically contingent rather than logically necessary.
As regards Kant's synthetic a priori judgement, which is about a priori pure and empirical intuitions, it is not about the identity statement "the postbox is red", rather it is about the identity statement "this is red", and as a priori "knowledge", logically necessary.
Synthetic a priori judgements
I've always thought the phrase "synthetic a priori" was wrong, as it mixes two fundamentally different things. To my understanding, within language are synthetic and analytic propositions, some knowledge can be a priori and some a posteriori and within logic is the necessary and contingent. It is as if one said "anger is a heavy thing", not to be understood literally but metaphorically.
"Synthetic a priori" means no more than humans are born with certain innate abilities, such as the innate ability to be able to distinguish between a loud and quiet noise, something hot and something cold, etc. Children don't need to go to school to be able to distinguish between a sweet and sour taste, as this is instinctive.
The term a priori knowledge is not correct either, in that humans don't have a knowledge of the colour red before seeing it for the first time, but they do have the ability to see the colour red before ever seeing it for the first time. As an analogy, a wine glass passively shatters when the frequency of an opera singer's voice matches the natural resonant frequency of the wine glass, it is not the case that the wine glass is an active participant.
The term "synthetic a priori" should be understood as an idiomatic expression rather than as a literal guide to Kant's doctrine of "transcendental idealism".
Better copy of Identity and Necessity
There is a web site, but one needs to sign in through your library.
https://academic.oup.com/book/36436/chapter/320710138
Anyway, I have to go now to see what Santa Claus has left under the tree.
Right, and our spacetime is necessarily what it is and could not have been different. Bye bye free will?
Sorry, but if you read the paper, Kripke posits the logicality on the empirical finding that Hesperus is Phosphorus. It's only a contingent identity statement upon observation that would allow us to conclude that it is Venus, in fact. Hence it is de facto a synthetic a priori upon examination via observation.
Could you elaborate?
Kantian transcendental idealism, not needing any inverted commas, is predicate on the possibility of synthetic a priori relations, and cannot stand without them, so must be understood as a literal guide to it, whether or not one regards the philosophy itself as legitimate.
In Kant, identity is the ground for truth in analytic judgements, which are never contingent. Synthetic judgements do not rely on identity, and the truth of them relies on the relation between its conceptions, hence is contingent. Kripke wants to unite the contingent with identity, which Kant deemed, if not impossible, then at least logically insufficient in regard to a brand new philosophy.
So maybe Kants term isnt a mere idiom after all. Which is neither here nor there with respect to the thread.
Does Kripke believe that it is possible for us to act differently than we actually act? It seems he doesn't, because our actions are parts of spacetime and spacetime is necessarily identical to itself, which means it cannot be different than it is and so our actions cannot be different than they are.
Could you provide that argument? I'm reading the paper again and see that Wiggins argument seems to point out the fact that sometimes we refer to the same object with two different proper names. But, he (Kripke) goes on to say that we discover these truths after observation, as in the case of Hesperus and Phosphorus being Venus.
I would argue that that is too strictly a transcendental argument. Every day we make choices where seemingly we could have done something otherwise. Even taking your argument to the extreme, there could be a possible world where causality would have allowed for a different event cone to allow a counterfactual to arise.
Yes, seemingly.
Quoting Shawn
Quantum-mechanical indeterminacy could do that. But a world with a different outcome of a quantum measurement would be a different world, with a different identity, than our world. And I cannot be in both worlds, if by "I" we understand someone who is conscious of being only in one world. The "I" in the different world would be my copy, a counterpart.
Yes, a world which is called a possible world ...
Quoting litewave
The issue of personal identity is somewhat justified by the fact that my identity is consistent with the world that my personal I obeys causality in. The degree to which I have influence over the causal chain of events culminating in my identity is not a philosophical question, in my opinion.
https://plato.stanford.edu/entries/identity-transworld/
Yeah, it's an important, but fraught, distinction. I suspect focusing on it will cause yet more confusion. It's a distinction that is important because of ambiguities in natural languages, that simply do not carry over to formal modal languages.
The de dicto interpretation has a wide scope for the modal operator:
[math] De\,dicto: \, \Box \exists (x) F(x) \\De\,re: \, \exists (x) \Box F(x)[/math]
The discussion on p.164 is to the effect that if we can have necessary properties for individuals then (1) must hold; that (1) says the same as that F(x), even if F is (x)(x=x).
So that page is mostly a justification for the soundness of the argument (1-4).
But the actual world is still necessarily identical to itself and therefore cannot be something different than it is. My actions in a merely possible world may be different than my actions in the actual world but my actions in the actual world cannot be different than my actions in the actual world.
This is germane to issues of free will and so on, but in a way logically precedes it. That is, we ought work out how best to talk about such issues prior to addressing them. Work out the grammar before we engage in the conversation.
All this by way of requesting that we stick to the text for now, rather than wander off on a tangent.
In the early part he's basically explaining the problems with looking at proper names as descriptions.
We learn empirically that Hesperus is Phosphorus. This couldn't be so if those two words were descriptions.
But we did learn that the star we see in the morning is the same as the star we see in the evening - they are both Venus.
So we can learn that two descriptions are of the same individual.
Now, necessarily, Hesperus is Phosphorus. But is is necessary that the morning star is the evening star?
If you really need a physical grounding for entertaining the notion of possible worlds, then assume the many worlds interpretation...AND there's no issue with things being deterministic given the MWI. You can still have counterparts and alternate versions of you.
The discussion on pg. 164 in N&N?
That's what I would call a category mistake.
Oh, okay.
Quoting Banno
I think it's important to make a distinction here about properties of objects and properties of individuals. Would it be accurate to label descriptions as also constituting properties also?
Hmm. Individuals as in individual constants... a,b,c...
and properties of individuals as in fa, fb, ga...
Descriptions are presumably formula that pick out at least one individual. "The man who invented bifocals" would be something like "The x such that x is a man and x invented bifocals".
Let's look at "the author of Hamlet", "H". This picks out one individual. "The author of Hamlet might not have written Hamlet" has ambiguous parsings.
It might be that Shakespeare did not write Hamlet; that the individual who did write Hamlet might possibly have not written Hamlet. Roughy
[math] \exists (x) (Hx . \diamond \sim Hx)[/math]
It could not have been that the person who wrote Hamlet, whoever that was, did not write Hamlet; it is not possible that the person who wrote Hamlet did nto write Hamlet.
[math] \sim\diamond (\exists (x) (Hx . \sim Hx)[/math]
The ambiguity dissipates because the scope of the existential and modal quantifiers is explicit.
[math] \exists (x)(Px ) \exists ( y)( By)(x=y)[/math]
"...here, x and y are both Benjamin Franklin, and it can certainly be necessary that Benjamin Franklin is identical with himself" p.166
So descriptions will not result in the sort of paradox Wiggins seems to have had in mind.
That's my reading to bottom of p.166. Kripke then passes on to proper names.
Can you elaborate about the scope? There is a large footnote about this in the text.
Quine had issues with extensionally opaque contexts, including modal considerations. Seems he wouldn't allow them as knowledge claims. He wouldn't have accepted [math] \Box Ha[/math], it seems.
Not in the scope of my thinking.
Note 4.
Yes, and I think this is where it gets interesting...
As Kripke mentions Kant's "synthetic a priori judgements" in the second sentence of his chapter, and as @Banno includes the same term in his OP, the meaning of "synthetic a priori judgements" cannot be irrelevant to the thread, otherwise, why mention it in the first place.
Quoting Mww
It deserves commas as it is a name, not a description. First, Kant was an empirical realist. Second, in edition B of the Critique of Reason, Kant inserted a refutation of idealism. Third, also in edition B, Kant said "Transcendental Idealism" was a poor choice of name. Fourth, there is debate as to how we can have transcendental knowledge, and whether what Kant calls transcendental knowledge is no more than knowledge by inference.
Quoting Mww
Kripke didn't want to unite contingent with identity, he wanted to unite necessity with identity. As he writes "According to this view, whenever, for example, someone makes a correct statement of identity between two names, such as, for example, that Cicero is Tully, his statement has to be necessary if it is true."
That might be a better way of putting it, but it really means the same thing due to the way that "contingent" is being used. The contingent statement is really just a special type of necessary statement, as a proper separation between the two is not provided. This is just a category error, but it is intended as the means to bridge the gap between identity and logical necessity.
The two of course are fundamentally incompatible, as identity is within the thing itself, while logical necessity is within the human mind. Therefore identity will always present itself as infinite possibility, hence fundamentally incompatible with logical necessity which is a limitation of possibility. That's why it's an exercise in sophistry.
Silly me, to think I posted a comment before reading the article.
Kripke starts off by writing that it is often taken for granted that contingent statements of identity are possible: How are contingent identity statements possible? This question is phrased by analogy with the way Kant phrased his question How are synthetic a priori judgments possible? In both cases, it has usually been taken for granted in the one case by Kant that synthetic a priori judgments were possible, and in the other case in contemporary philosophical literature that contingent statements of identity are possible."
He later writes that he believes that identity statements are necessary and not contingent: "To state finally what I think, as opposed to what seems to be the case, or what others think, I think that in both cases, the case of names and the case of the theoretical identifications, the identity statements are necessary and not contingent. That is to say, they are necessary if true; of course, false identity statements are not necessary. How can one possibly defend such a view? Perhaps I lack a complete answer to this question, even though I am convinced that the view is true."
Although Kripke writes "x has a certain property F", one questions how this fits in with Russell's Descriptivism where x is its set of properties.
How can an object such as an apple, having a self-identity, have infinite possibilities ?
Superman might have taken on a different secret identity - Lois Lane, even. But in such case, Lois Lane would not be the woman we know who loves Superman, and Clark Kent would not be the man we know as 'Clark Kent' (viz, Superman), but a mere bespectacled reporter of no interest to us. But given that it turns out that Clark Kent is Superman in disguise, necessarily, Clark Kent is Superman.
As usual, necessity doesn't constrain reality, only language. 2 Rabbits + a lot of lettuce and carrots = 137 rabbits + a lot of droppings. Blame it on the boogie.
All the posts by unenlightened are necessarily unenlightened's posts. If my account was hacked, there might be posts with my name on them, but they would not be my posts. Contrarywise, if I had a sock-puppet account, all those posts would necessarily be unenlightened's posts too, though they had another name on them.
Ehhhh ..as Kripke says, guy writes a book on something, another guy writes a book on how wrong the first guy was. Been that way since Day One. You and I, operating under the auspices of basic logical laws, reject the accordance of contingency with identity, but if somebody comes along and tweaks this definition, or fiddles with that perspective, he can obfuscate the established laws accordingly, and posit something nobodys ever thought of before.
If you and I are going to get along with the pure analyticalists, we have to concede that when Kripke says, for any two objects x and y, if x is identical to y ., it is more the case x is congruent to y rather than x being identical to y. Pretty simple, really; x is x and therefore not-y. Two objects having common properties is not the same as two objects being identical.
As for the category mistake, heres my agreement with it:
For every property F .. F can be any property, such that if F belongs to x, and if x is identical to y then it is necessary that F belong to y. If F is the property of being round, and if x is round and y is identical to x, then y is round. Thats fine, in that x is, e.g., a round cue ball and y is, e.g., an identically round baseball. Which is also fine, insofar as the conditional is for any two objects, satisfied by one cue ball and one baseball.
It remains that a cue ball is not a baseball. But if x is to stand as identical to y, one of every property F is obviously not sufficient to cause x to be identical to y because of F. So keep adding Fs to x, maybe hundreds of Fs, such that when those properties also belong to y, they become closer and closer to both x and y being either a cue ball or a baseball. Still satisfies for any two objects, as well as for any property F which belongs to x also belongs to y.
The kicker: For every property F ., in order for the cue ball x and the baseball y to be identical, every property F must belong to both equally. It follows that in order for x to be identical to y, a space F belonging to x is the same space F belonging to y, and x and y simultaneously be commonly imbued with every other possible F equally. But two objects sharing the same space F is a contradiction, which negates the case. It must be, then, that they occupy different space Fs but still be commonly imbued with every other F equally. How does that happen, you ask .surely with bated breath. Well ..the space of x in one world, and the space of y in another world. What else?????
Hence contingent identity, contingent on the possibility of other worlds. Under the assumption of another merely possible world, however, such world can only have possible space, from which follows only a possible y can have the property of possible space, or, more correctly, only a possible y can occupy a possible space possibly, which reduces to a real x being identical to a possible y, which is not the original argument. In effect, then, in order to assume x = y identity necessarily, mandates a veritable maze of contingent possibilities.
And thats a category mistake. Dunno if its yours or not, but it works, doesnt it? The article goes on to circumvent these mistakes, re: let us use necessity weakly, or actually, to deny them altogether, re: I will not go into this particular form of subtlety** here because it isnt relevant, in order to justify the notions contained further on in it.
But still, if a theory starts out illogically, and if the circumventions are not all that valid, wouldnt it jeopardize the whole? Kripke is just saying, if it was this way, we could say this about it. But if it couldnt be this way, why still talk as if it could? He goes on to talk about it in a different way, thats all.
(** existence as a predicate, reflecting on existence in possible worlds)
In the search for a Superman who isn't a Clark Kent, one will never be found iff Superman is defined as Clark Kent.
Such are the consequences of identity and necessity.
Yet language rarely works that way. Another world's Superman can have all the properties as our world yet not be Clark Kent, yet we'd call them the same things.
So what makes Superman be Superman, if not for his being also Clark Kent? Which properties are accidental versus essential? Which properties of primary versus secondary? Does this get us anywhere, or do we just end back up at meaning is use, and admit that the entire hypothetical construct of prescribing meaning to words (e.g. Clark Kent = Superman) doesn't exist in our linguistic world and that's what caused this whole quandary in the first place?
Imagine Lois travels to an alternate universe where Superman landed in Mexico instead of Iowa. He was raised by the Cortez family and they named him Julio.
So what makes this guy Superman?
De re modality, to answer your question...
De re and de dicto are about how one interprets an ambiguous statement. How does that tell us something about how some guy in an alternate universe is Superman?
Has nothing to do with its meaning; only with juxtaposition. If Kant can justify the one, then it is reasonable to suppose Kripke should be able to justify the other. Successors denied the one, successors may well deny the other. Nowhere in the article is one related, compared, or otherwise connected, to the other, and because it isnt, whatever meaning it has, is irrelevant with respect to the article.
-
I have two searchable editions, in which transcendental is found 568 times but transcendental knowledge doesnt come up at all. You probably meant knowledge of the transcendental, which was never intended to be knowledge as such. Transcendental, in its strictest sense, is merely a sub-system of thought, premised on the complete absence of anything empirical. Included in that, are conditions of which there is no conscious awareness, hence cannot be known. In a purely logical system they dont have to be known; they only need to be non-contradictory. As such, the subject knows of a logical validity, but not the objects that belong thereto.
Quoting RussellA
Yes, that being material idealism of Descartes and Berkeley. In A, it is the fourth paralogism.
Quoting RussellA
Yes, but more than that. (A370)
Quoting RussellA
Then why would he present as a problem of philosophy, how are contingent identity statements possible?. Upwards from pg10, does he admit identity statements are necessary, and not contingent. If the second, why ask the first?
No more Kant. will take us to TPF court, and I cant afford the fines.
Because when we speak about Superman, we can posit his existence in a possible world as a counterpart or a counterfactual. Whereas, people claim that this is impossible because they're thinking about the whole issue as de dicto, Superman couldn't be anything other than himself as we have come to know of him in our world.
It depends whether the name Phosphorus is a reference or a description.
If Phosphorus refers to the planet Venus, through empirical observation, we can infer, along the lines of Hume's constant conjunction, that Phosphorus in the morning is the same body as Hesperus in the evening. From (1), x is Phosphorus, y is Hesperus, and as both x and y refer to the same body, x is identical to y.
If Phosphorus is a description, from Russell's Descriptivism, Phosphorus is a description of a set of properties, whereby Phosphorus has no existence over and above its properties. From (4), x is the set of properties bright, visible, no rings, y is the same set of properties bright, visible, no rings, and as both x and y refer to the same set of properties, x is necessarily y.
IE, as regards referring, two bodies having the same properties, but each body existing over and above its properties, are contingently the same a posteriori. As regards description, two sets of the same properties are necessarily the same a priori.
Neither can I. :smile:
Let us suppose he can leap tall buildings in a single bound, that should be enough to claim he's a superman. To be sure, he's not the Superman of we've defined the Superman as the single entity in our world.
But such are definitional decisions. We could define Julio as Superman if we so wished.
If a bachelor is an unmarried man, they can exist anywhere, but the bachelor, if defined as only that one, can exist but one place.
What have I missed?
This seems the answer implicit in the phrase "identity and necessity." That which we identify and define as a specific entity, by necessity is that specific thing, existing in but one world. To allow it in other worlds, eliminates its identity.
Not in de re modality.
True, although there seems to be a spectrum from a completely defined entity (like Superman as we know him) all the way to a Superman who is radically different from ours, so that the rigid designator, "Superman" is almost devoid of any essential properties. I think @Banno likes the latter extreme where rigid designators are hollowed out, although I think he would agree that we can't hollow them out completely because that would become meaningless.
For the most part, we do have some essential properties in mind when we talk about hypotheticals.
Those properties may be specifically mentioned, or we may discern them from context. But however those essential properties are specified, they become necessary in the context of the statements in which they appear, even though we also know they're contingent.
The point of it is just to explore the way we think and speak.
I don't think "de re" is a kind of modality. It's an aspect of intensional speech, like "Brian believes someone likes potato chips."
I look at it more as if there are a handful of typically associated properties attached to the object and if a certain number are present, it's considered the object.
It's like a medical syndrome. If you have 5 of 8 symptoms, you have ADHD, but no one is essential. Sort of like that. That dispenses with the essence problem. I'd argue I've described what is meant by the family resemblance.
I think you at least have to have a common origin for all the possible versions of you. Like could you have been born female?
An ableist slur, of course.
De re is about something. Have you read the wiki on de re-de dicto?
That's you about to get pooped on.
It sure is.
- de dicto de re
That's about metaphysical de re/de dicto. That's a question about whether what I believe about you is a property of you, or is it just a relation between me and a proposition. Or something like that.
It's important because people get somewhat confused when stipulating a de re modality in a possible world whilst believing that the identity of the individual only obtains de dicto, in our world.
Are you too seeing that?
If we substitute a and b for x and y, with a few more brackets to explicate the scope, we have
[math]((a=b) . Fa) \supset Fb)[/math]
and derive
[math](a=b) \supset \Box (a=b)[/math]
And so to the consequences of this derivation. Quine argues, roughly, that the fact that Hesperus is Phosphorus was discovered, and so is contingent. That Guarisanka was discovered to be Everest - I checked this with Nepalese friends, and it is indeed incorrect, they are distinct mountains -
and so on. The suposition here is that an identity that we discover cannot be a necessary identity, and so there must be something amiss with the derivation (1-4).
Many problems occur as a result of using a nomenclature form the 1200's. So don't.
I'm not sure everyone knows that. But just to clarify we usually appeal to de dicto (from our world) and then stipulate a de re about Superman in a possible world, as a counterpart or counterfactual from the world where we came to know about him.
Just wanted to make sure we're quantifying correctly here about Superman's identity obtaining even from de re modalities, with respect to de dicto knowledge we have about him in our world.
Thanks.
So can you phrase that in terms of boxes and diamonds?
And if you can't, do you actually understand it? OR are you sliding along an ambiguity?
Let go of fixed plans and concepts, and the world will govern itself. (Tao Te Ching, 57)
:nerd:
Russell tried to achieve some semblance of certainty by supposing that the only real names were "this" and "that", and what otherwise appears to be a proper name is actually a description.
It wasn't all that successful; things got complicated.
Russell would have had us use only predicate such as f,g,h..., and individual variables, x,y,z..., but not individual constants, a,b,c... Russell worked out a way to replace proper names with definite descriptions - a definite description being a sequence that serves to pick out exactly one individual. Importantly, he did this using an identity statement, so opening himself up to the sort of modal considerations we have before us.
Anecdote: I took philosophy at UCLA and had Donald Kalish as my logic professor. He told an interesting story about how he and a partner were all ready to give a talk on a paper on logic only to find out this 16 year old kid, Kripke, had beaten them to the punch.
Nope.
Quoting Shawn
Thought not.
A replica of me, but for being female, would still be a Hanover, I think.
It's a ship of Theseus sort of question. Which board is essential to maintain identity? A transsexual would not claim loss of essential identity upon change of gender. Interestingly, they'd claim not just maintenance of identity upon transition, but would claim that the removal of those boards (so to speak) was their way of purifying their identity.
Your example was a loaded one, so perhaps another example would work better.
What I can say is that there is but one world with a Hanover where Hanover is defined as the one living in this world, and it would do you no good to search for Hanovers in other worlds because each one you find will not be a Hanover by definition.
There are no worlds with all white penguins where penguins are defined as being partially black. If you drop the necessity of identifying them as partially black, there will be white ones in some possible world.
But this is obvious and not interesting, so where have I missed something?
The identity is within the object itself (as the law of identity states, it is the same as itself). The object's identity appears to any one of us as infinite possibilities because I can name it whatever I want.
Quoting Mww
Well, this does little for me. I'd rather stick to the Leibniz principle, and hold the belief that if any true statement made about x is also true about y, they are really one and the same thing. Then it's a mistake to talk about what "x" and what "y" refer to as if it were two different things, because it's really one and the same thing. To say that they each exist in a different space in a different world doesn't do it for me, because that is actually saying something different about each of them.
Quoting Mww
Yes, I'd say that's a good description of the category mistake involved, it annihilates the separation between possible and actual. It's actually a very similar error to one which is common in mathematical axioms, especially ones which deal with infinity. You'll see for instance that a "countable set" is one which can be counted using the natural numbers. But the natural numbers are not actually countable, being infinite. So they take the true defining feature of the natural numbers (impossible to count, by definition of "infinite"), and replace it with a different defining feature (logically possible to count), and come up with "countable".
Quoting Mww
That is the weird and wonderful reality of the world we live in. We still go on to talk about it simply because it is possible to talk about it. Ultimately, this ought to become the central point, the reality that It is possible to say things which are completely untrue, and still have people make a very good understanding of what you have said.
So, what are they actually understanding in this situation, we might ask. When someone has a very clear and accurate understanding of something which is false, we can't say it's a misunderstanding, because they actually do understand. What is it that is understood then? What is the subject matter of falsity? Is it "possibility"? In a way, it must be, because the only way to give reality to possibility is to annihilate the reality of truth, and that seems to leave us with falsity. The only remedy, if we desire to push forward in this vein of understanding nothing (which can't be called misunderstanding) is to equally annihilate falsity, leaving us with something like a model-dependent realism. But this means we must completely deny identity, so it requires an ontology similar to dialectical materialism.
And this is the problem Kripke is addressing. If your identity is a description or definition, then it makes no sense to say you could have become a plumber.
But we can say that. There's a possible world where you're a plumber, so it doesn't look like your identity can't be a description. So what is it?
That John does some plumbing work is not part of his identity, in that neither is holidaying in Paris for ten days part of his identity.
Russell says that the name John is a description rather than a reference.
We can say "John is in Paris", "John is a barber", "John could running for the bus" or "John could be a plumber".
I am not defined as a person by where I live or what I do. The fact that John is in Paris, is doing some barbering work, running for the bus or doing some plumbing work is not part of his identity, and therefore not part of the name John, is not part of what the name John describes.
The sentence "John is a barber" illustrates the metaphorical aspect of language. John's identity is not that of being a barber, in that water is H2O, it means "John is doing some barbering work".
As the fact that John is in Paris is not part of the description of John's identity, John could equally well be in Rome. As the fact that John is doing some barbering work is not part of the description of John's identity, John could equally well be doing some plumbing work.
The first part of this essay explains why that's problematic. How do you respond to Kripke's point?
By the law of identity, a thing's identity is the thing itself. To say that a thing's identity is a description, definition, or even a name, is to make the category mistake of saying that the thing's identity is what someone says about the thing, rather than the thing itself. The name of a thing is a representation of the thing's identity, not its identity.
If you allow this category mistake into your thinking, then you allow for all sorts of sophistry to invade your mind, such as the questions about Hesperus and Phosphorus, and the ship of Theseus. Instead, we ought to be content in knowing that we simply cannot make any true identity statements, and that's just a basic feature of human knowledge.
What's an identity statement?
As used in that post, any statement which claims to reference the identity of an object. Our only access to an object's identity is through the object itself, so we reference the object itself, and we might do this with a name. If we claim to reference the object's identity, and then proceed to make statements about the object's identity as if it were something separate from the object, we enter the fantasy world of sophistry. There really is no such thing, so if we insist that there is, it could be absolutely anything, so sophistry runs amuck.
Here's an example of such a sophistic reference intended to create an independent, or separate identity:
Quoting Banno
See what happens? At the first attempt to create such an independent identity, immediately it is evident that something is "amiss". That's because the thing itself with its true identity is understood as independent, so it appears like it's identity must be "discovered", but whenever we try to talk about a separate identity, this must be something created by us.
If we allow the "discovered" identity, we allow Platonism, as separate, independent Forms which are discovered. If we allow a created identity, then we reject the true identity within the thing, as inconsistent with the created identity, and we have a type of anti-realism. The only solution is to deny a separate identity altogether, to establish a ground free from such sophistry.
I think you misunderstood what he meant by discovering identity. It appears that a lot of the time identity is something we declare. That's what's happening when a baby is baptized by the Catholic Church. The baby is henceforth identified by that name.
There are other ways to identify that kid, though. I would tell the police that he has a mole on his knee.
In Spanish there are two different words for predication. One signifies identity: things that don't change. The other signifies passing states (although it's not always cut and dried, but that's the basic idea.)
That's one reason we shouldn't get carried away with philosophizing by the way people speak. Different languages are structured differently and so would produce different philosophies.
I covered that, and probably best to leave it at the same kind of thing.
Proper names refer to descriptions.
I wrote: "As the fact that John is in Paris is not part of the description of John's identity, John could equally well be in Rome. As the fact that John is doing some barbering work is not part of the description of John's identity, John could equally well be doing some plumbing work."
The Ancient Greeks saw in the evening something having the properties brightest natural object in sky, visible by naked eye during day, has no rings and tagged it Hesperus. They also in the morning something having the properties brightest natural object in sky, visible by naked eye during day, has no rings and tagged it Phosphorus. Pythagoras recognized that Hesperus and Phosphorus were in fact the same object, the planet Venus.
Kripke wrote: We may tag the planet Venus some fine evening with the proper name Hesperus. We may tag the same planet again someday before sun rise with the proper name Phosphorus. ....................When, at last, we discover that we have tagged the same planet twice, our discovery is empirical, and not because the proper names were descriptions.
Does the name Hesperus refer to Venus or describe its properties brightest natural object in sky, visible by naked eye during day, has no rings, appears in evening?
If Hesperus refers to Venus, does Venus refer to Venus or describe its properties brightest natural object in sky, visible by naked eye during day, has no rings, appears first in the morning and then in the evening?
Venus cannot exist independently of its properties, in that if Venus had no properties, Venus wouldn't exist. If I looked into the sky and saw no properties I would see no Venus. As Venus would not exist if it had no properties, Venus cannot refer to Venus but can only describe its properties. Venus cannot create itself by referring to itself.
IE, the proper names Hesperus and Phosphorus are descriptions, as in Russell's Descriptivism.
Does a single object as a thing in itself have infinite possibilities, or do we, as observers, see infinite possibilities in a single object ?
I don't understand the logic of (1)
Kripke wrote: "for any objects x and y, if x is identical to y, then if x has a certain property F, so does y"
The sequence of (1) is:
A) starting with object x which has property F
B) knowing that object x is identical to object y
C) I then know that object y has the same property F as x
My supposition is that i) if there are no properties, then there is no object ii) if I cannot see any properties, then I cannot see any object.
However, this sequence seems more logical:
A) As object x has property F, I can know object x
B) I can only compare object x with object y if I know object y, and I can only know object y by knowing its property G. Therefore, I must know object y's property G before being able to compare object y to object x. If I didn't know object y's property, I wouldn't know that object y existed.
C) When comparing object x and its property F with object y and its property G, in discovering that property F is identical with property G, I then know that object x is identical to object y
IE, the problem with (1) is how can I know object x is identical to object y before I know object y's property?
Am I missing something.
Quoting Banno
Even though I can't formalize my statement. I believe I understand it. :smile:
Happy with this thread so far? The folk who really need to read the article have just voiced their opinions, again, without addressing, and probably without even reading, the article.
Anyway...
Not really. I already said what I thought worth mentioning.
Quoting Banno
I tried, you tried. There's nothing more to address here. I consider the thread finished before we even started.
We've seen in the posts hereabouts the tendency to jump to trying to solve the problem before one works out the logic involved, before considering the way language works here.
If identity statements are true, then they are necessarily true.
Now I agree with him, because I find the argument that follow convincing. I think he presents a way of talking about necessity and identity that allows us to do so in a way that is coherent and consistent, and that the alternatives do not give us the same clarity.
Those with the patience to follow the discussion might agree or disagree, but what they have to say will be of more value than the views of those who lack such patience.
Examples: "Benjamin Franklin" picks out the same individual in any possible world, but "the inventor of bifocals" doesn't. Someone else, not Ben Franklin, might have invented bifocals.
Of course, Franklin may have had some other name, or someone else might have been called "Ben Franklin". But notice that "Ben Franklin might have had another name" is a sentence about Ben Franklin. The rigid designator still works, And "someone else might have been named 'Ben Franklin'" is not about Ben Franklin, but about his name. Again, the rigid designator still works.
And here we can see one way to weaponise this account. Ask who "Ben Franklin might have had another name" is about. It appears to be a sentence about Ben Franklin. That is, the Ben Franklin with whom we are familiar and the Ben Franklin who might have had a different name are the very same individual. In particular, it does not seem to be about someone else, Franklin's counterpart in some other possible world.
This is directed at many of the post hereabouts, but I've jumped ahead, to Lewis. Back to the text.
Those grammars that adopt counterpart theory tend to greater complexity.
The juxtaposition here is between two ways of talking about possible worlds. On the one hand, we have the view that when we talk about the individuals in other possible worlds, it is not immediately apparent that they are the same individuals as in this world. Kripke uses Nixon for his example; we might modernise it while keeping the tone. What if Donald Trump were a prominent member of Extinction Rebellion? What things would be different? We might have fun with such considerations.
Someone will say "But wouldn't such a Trump no be so different to our Trump as to be a entirely different person? By what criteria could we consider a Trump who superglues himself to a petrol tanker or some such protest, to be the same Trump who approved the wholesale destruction of the environment? "
The picture here is of possible worlds as places we might visit, and inspect to see if some of the individuals there are like the individuals in our world. We venture into a possible world in which it makes sense to ask "Is that really Trump, blocking the bridge?"
The contrasting view is that possible worlds are little more than a way of talking about how things might have been, that, as I have put it elsewhere, possible worlds are stipulated rather than discovered.
When one supposes that Trump had joined Extinction Rebellion, one does not find oneself in the position of having to demonstrate that the supposition is about Trump. Here Kripke weaponises the question. As if the conversation might go:
"Suppose Trump had joined Extinction Rebelion..."
"Ah, yes, so how would you know that it was indeed Trump who had joined Extinction Rebellion..."
Well, I know because that was the very stipulation from which we began. It wasn't "Suppose that in some other possible world there was an individual with certain characteristics in common with Trump in our world who nevertheless was not Trump but who joined Extinction Rebellion..."
Possible worlds do not "exist out there, but very far away, viewable only through a special telescope" (p. 175). We make 'em up. And we make 'em up how we like.
A close error would be to suppose that possible worlds are the same as the multiverse of pop physics. These two ideas come from very different backgrounds. Any suggestion that they are the same thing would require considerable argument from both physics and logic.
(Edit: Apologies - a distraction prevented me finishing this post. I was thinking of just leaving it as is, since it's possible that this is the part that will meet with the most disagreement, and it would have been amusing to see if anyone actually read the page.)
Here are Kripke's definitions:
Two metaphysical terms:
Something is necessary if it is true and it could not have been otherwise.
Something is contingent if things could have been otherwise.
An epistemological term:
Something is a priori if it can be known independently of experience.
It should be clear that being a priori is quite different to being necessary. If they are related so that being one implied being the other, some philosophical argument is required in order to demonstrate that relation.
As Kripke says, "neither class of statements is contained within the other" (bottom of p.177).
The suggestion is that Kant took necessary and a priori to be interchangeable, and similarly for a posteriori and contingent. If he did, he was certainly wrong. That he did, I've not the background to decide. @Mww may be able to help here.
Metaphysical terms needs an edit.
There's this additional complication, the use of "synthetic" and "analytic" in the place of "necessary" and "contingent".
This seems to be equating a grammatical difference with a modal one. We supposedly know the truth of analytic statements just by considering their place in our language. But the truth of synthetic statements requires consideration of how things are in the world, hence usually involving experience.
So we might add to Kipke's list
Two grammatical terms:
Something is analytic if its truth can be known solely by the terms involved.
Something is synthetic if its truth is not known solely by the terms involved.
And again, what seems clear leads on consideration to a great deal of complication - including a long-forgotten discussion between Quine and Chomsky, of all folk.
It might suffice for our purposes in considering Kripke's article, to just point out that it is not obvious, without further consideration, that this grammatical distinction is the very same as Kripke's metaphysical distinction.
Quoting Mww
Cheers, done.
There is a serious caveat here, in that for Kant, when he speaks of the a priori he means pure a priori, meaning having nothing to do with any experience whatsoever. He set this as a definition, probably so he didnt have to modify the term every time he used it. Conventionally speaking, on the other hand, when the term a priori is used, or even when the uninitiated read CPR and find Kant using the unmodified term constantly, it refers to those conditions of no immediate experience, but grounded nonetheless in antecedent experience.
With respect to Kripkes metaphysical terms, he actually says independently of ALL experience, which is Kants pure a priori, but a priori in its conventional sense, as most are inclined to use it, is not necessarily independent of all experience.
. In the first place, if we have a proposition which contains the idea of necessity in its very conception, it is a priori .
..Now, that in the sphere of human cognition we have judgements which are necessary, and in the strictest sense universal, consequently pure à priori, it will be an easy matter to show. If we desire an example from the sciences, we need only take any proposition in mathematics .
So it is that necessity and a priori are always connected, through the LNC, so if one wants to call them interchangeable because of that connection, I guess he could. Theres so much more to all this, that would show they are not, but ..some other time perhaps.
Quoting Banno
The a posteriori is always contingent, through the principle of induction, but again interchangeable?
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Quoting Banno
Maybe equating the relational with the modal. Still a catastrophic rational error. Necessary/contingent are modal categories, which are logical conditions; synthetic/analytic describe relations of conceptions in propositions, which are relational conditions.
I see what you did here, letting me in without fear of court. I owe you a toddy. Or two.
Quoting Mww
Notice that what you have said here is contrary to the stuff around p.167. So according to Kripke, that Hesperus is Phosphorus is known a posteriori, yet not contingent.
So there is disagreement between Kant and Kripke?
I'd like to consider the argument that uses the principle of induction. What is it? I gather that it also disagrees with Kripke's account.
Quoting Banno
Here's were Kripke expresses just this view.
Here the emphasis is somewhat different, since the point at issue is that "it is not trivial that just because such a statement is necessary it can be known a priori... this shows that even if everything necessary is a priori in some sense, it should not be taken as a trivial matter of definition" (p. 178).
If a proper name such as Hesperus refers to a set of properties that have been named, I can understand and agree that if x is y then x is necessarily y.
How can a necessary identity statement be derived from a contingent identity statement
Kripke wrote: "most philosophers have felt that the notion of a contingent identity statement ran into something like the following paradox."
(1) If x is identical to y, and if x has property F, then y has property F
(2) Every object is necessarily self-identical
(4) If x is identical to y, then x is necessarily identical to y
This idea was reinforced by Wiggins, who said: "Now there undoubtedly exist contingent identity-statements. Let a = b be one of them. From its simple truth and (5) [= (4) above] we can derive ? (a = b). But how then can there be any contingent identity-statements?"
Kripke argues that Phosphorus is Hesperus is a necessary identity statement
Kripke first writes that the common view is that Phosphorus is Hesperus is a contingent identity statement: "We may tag the planet Venus some fine evening with the proper name Hesperus. We may tag the same planet again someday before sun rise with the proper name Phosphorus.............When, at last, we discover that we have tagged the same planet twice, our discovery is empirical...........Surely no amount of a priori ratiocination on their part could conceivably have made it possible for them to deduce that Phosphorus is Hesperus."
However, Kripke later writes that he believes that Phosphorus is Hesperus is a necessary identity statement: "To state finally what I think, as opposed to what seems to be the case, or what others think, I think that in both cases, the case of names and the case of the theoretical identifications, the identity statements are necessary and not contingent."
Is (1) really a contingent identity statement ?
Kripke is saying that although (1) is a contingent identity statement, (4) can be derived from it, but (4) is a necessary identity statement, which seems a paradox.
However, is it really the case that (1) is a contingent identity statement ? (1) in being a logical implication, involving the terms if then, is, in Kripke's word "an a priori ratiocination", independent of empirical experience. However, by Hume's problem of constant conjunction, we can never know from empirical experience that Hesperus is identical to Phosphorus, we can only infer it.
For example, I observe Phosphorus at 9am and Hesperus at 9pm having a 180 degree separation. As I don't know what happened in the intervening period, I very weakly infer that Hesperus is Phosphorus. I observe Phosphorus at 9am and Hesperus at 9.01am having a 0.25 degree separation. As I don't know what happened in the intervening period, I very strongly infer that Hesperus is Phosphorus. No matter how close the period of time between my observations, I can never determine just from a posteriori empirical evidence that Hesperus is Phosphorus. The most I can do is infer through logical reasoning that Hesperus is Phosphorus. My logical reasoning is a priori in the sense that it is independent of empirical observation, although my logical reasoning is based on a posteriori empirical observation
We can never know from empirical evidence that Hesperus is identical to Phosphorus, the most we can do is make the judgement from logic and reasoning based on evidence that Hesperus is identical to Phosphorus. (1) is a statement about identity that is based on logical reasoning about empirical evidence, and therefore cannot be described as a contingent identity statement.
As both (1) and (4) are statements of logical necessity of empirical evidence, this doesn't support Kripke's statement that "This is an argument which has been stated many times in recent philosophy. Its conclusion, however, has often been regarded as highly paradoxical."
Its is an empirical fact Phosporus is Venus, and, it is an empirical fact Hesperus is Venus. It is therefore an analytical cognition, hence necessarily true, that Phosporus is Hesperus, in that it is just saying Venus is Venus. Technically, this just means there are no conceptions belonging to the one that do not belong to the others. But it is nevertheless contingent, re: not necessary, that the second planet from the sun is called out by any of the names Venus, Phosporus or Hesperus, such names arbitrarily determined by whoever took it upon himself to assign them. As Kripke said, it could have turned out the other way, or, even moreso, the same planet could have been given any name that didnt already belong to an object known to the one assigning. Nevertheless, identity belongs to the object necessarily, indicating how we are to be affected by it, as a function of our human sensibility, yet naming belongs to the agents cognition of the object, merely indicating how it is to be represented, as a function of our human intelligence.
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On the principle of induction:
Secondly, an empirical judgement never exhibits strict and absolute, but only assumed and comparative universality (by induction); therefore, the most we can say isso far as we have hitherto observed, there is no exception to this or that rule. If, on the other hand, a judgement carries with it strict and absolute universality, that is, admits of no possible exception, it is not derived from experience, but is valid absolutely à priori.
Knowledge is experience, experience is always changing with time, so knowledge is always changing with time, therefore knowledge is contingent on time.
.. Experience no doubt teaches us that this or that object is constituted in such and such a manner, but not that it could not possibly exist otherwise ..
Quoting Banno
Of course, in that he is analytical, Im continental, with all the implications carried therein. But hes famous, got letters after his name, might even hold a chair, and Im none of that, so ..
Are we up to the wooden lectern?
I am surprised you say "hence necessarily true, that Phosphorus is Hesperus", as you also quoted Kant from the Critique of Pure Reason: "Secondly, an empirical judgement never exhibits strict and absolute, but only assumed and comparative universality (by induction); therefore, the most we can say isso far as we have hitherto observed, there is no exception to this or that rule". (B4)
Running low on chilled Perrier over Christmas ? :smile:
I see something in the morning sky that is bright, visible, ringless and name it "Phosphorus". My knowledge that there is something in the sky is a posteriori. As I could have chosen any name, the connection between the name "Phosphorus " and something in the sky is contingent.
Henceforth using the convention that "Phosphorus" exists in language and Phosphorus exists in the world as a set of properties.
After looking at the sky on successive days, I infer that Phosphorus is Hesperus a posteriori. The connection between Phosphorus and Hesperus is contingent because it is an inference.
I can then say "I believe that Phosphorus is Hesperus". As I can only infer that Phosphorus is Hesperus a posteriori, the statement "I believe that Phosphorus is Hesperus" is synthetic
For convenience I rename both "Phosphorus" and "Hesperus" as "Venus". As I could have chosen any name, the connection between the name "Phosphorus" and "Venus" and between "Hesperus" and "Venus" are contingent. The statements "Phosphorus is Venus" and "Hesperus is Venus" are synthetic, as I can only know that Phosphorus is Hesperus a posteriori.
However, even though I can only know Hesperus and Phosphorus a posteriori, and as I can only infer that Phosphorus is Hesperus, then Phosphorus being Hesperus can only be contingent, the statement "if Phosphorus is Hesperus then Phosphorus is necessarily Hesperus" can still be true, as it is a logical implication.
The molecular theory of heat part of the discussion had me really interested. I don't think I'd say that the case of molecules is the same as the case of the lectern, though, or the sensation of heat. One of the most obvious differences is that "H2O" does not pick out any particular molecule -- that's something that's always interesting to me about chemistry is that it looks at physical systems in aggregate, and if aggregates have names then there are as many aggregates in a sample of water as there are the factorial of molecules (EDIT:I might have that technically wrong -- it's been more than a minute since statistical mechanics, but the factorial of the number of molecules will get you in the ball park of the number of subsets. I can't remember when substitution is and is not allowed), and "H2O" could pick out any one of the groups within. So it doesn't really name any one of the molecules but rather says "of the molecules that are here they are composed of two hydrogen and one oxygen" -- but that, too, is funny because we don't really "see" molecules. If we're defining heat in terms of sensation, then molecules should be the same and what we actually interact with are properties of matter, and molecules are used to explain the properties of matter.
Which is to say, I highly doubt that "molecular movement" is a rigid designator -- same with water and heat and H2O. Not only could it have been otherwise, it's still possible for water to not be H2O. We just happened to build our theories like that and like them this way.
But, that doesn't speak against the general argument, only that particular example (and, I actually wonder, given that particular example -- would the analysis go the same for the mind-body problem as Kripke lays it out?) I just think that particular example is much too complicated -- the lectern example seems to work for me. And, in general, I think there's something to names being rigid designators, and I agree with Kripke that there's no reason to give predicates a priority over names -- that's just putting rigidity on the other side of the predication, so would fall to the same sorts of doubts.
((EDIT: As an afterthought, now -- might be a good example to set out "equiprimordial", but in analytic terms -- seems to have a similar meaning))
Explained in the rest of what I said, maybe? Note the CPR quote references universality with respect to empirical judgements, where I referenced necessity with respect to analytical cognitions, both under the a priori umbrella.
That there are two names representing a singular whole object makes explicit the conceptions by which the first name represents that object, reside in the second name equally, such that the second name represents exactly the same whole object, hence Hesperus is Phosphorus is a pure analytic proposition, hence necessarily true. It is no less analytical than the proposition bodies are extended.
Now you might say, to point to one is not to point to the other. But one does not point to a name, but the thing represented by the name, so he points to the same thing, the same aggregate of conceptions, even if not the same name.
Quoting RussellA
Yes, the names are contingent, fully arbitrary, yet usually related to something antecedent to the name itself, in this case a combination of Roman and Greek gods. Nevertheless, the conditions under which the names are chosen, the connection between the representation and that which is represented, is not contingent, but given a priori in the synthesis of conceptual representations with sensory representations, which makes any name itself a mere representation. The names of the gods are just as analytic and necessarily true, insofar as the Greek god Phosphorus cannot refer to anything other than that for which it was cognized.
To say those names are contingent merely because those names were chosen arbitrarily, is nowhere near the logical contingency indicated in epistemological metaphysics. Or, to put it in simplest terms .see how easy it is to force language to screw with reason.
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quote="RussellA;767433"]even though I can only know Hesperus and Phosphorus a posteriori[/quote]
Thats not quite right. You can only know of an object in space a posteriori. The object in space is not its name, it is just a thing. The name you know a posteriori because you learned it through experience, as opposed to being the one that installed the name on the object. But to know the object as such, is not to know the name of the object as such, insofar as they are completely different perceptions. You are merely relating the object to the name, which you cannot do a posteriori, but only in reason a priori, yet under a posteriori conditions.
We're dealing with transitivity: If (a=b) and (b=c) then (a=c). Hence we can agree that
Necessarily [if (a=b) and (b=c) then (a=c)]. I gather something like this is your "analytical cognition".
But we are substituting this into an opaque context - whether they are empirical facts.
In your argument you have:
Its an empirical fact that (a=b)
Its an empirical fact that (b=c)
Necessarily [if (a=b) and (b=c) then (a=c)]
Hence necessarily (a=c)
That doesn't work, since the argument changes modality form being empirical to being necessary.
You might suppose that since it's an empirical fact that (a=b), it is not a necessary fact that (a=b). But that would be question-begging, since what is in contention is exactly whether the empirical fact that Hesperus = Phosphorus is a necessary fact. And in any case that would give
Its not necessary that (a=b)
Its not necessary that (b=c)
Necessarily [if (a=b) and (b=c) then (a=c)]
Hence necessarily (a=c)
Which doesn't work, either.
In nay case, the contention is not whether Phosphorus is Venus, but whether Phosphorus is Hesperus. That Phosphorus is Hesperus is a discovery made by those observing the night sky. And yet that Phosphorus is Hesperus is a necessary fact.
Another way to set out the issue is that, had it been instead discovered that Hesperus is not Phosphorus, we would not be talking about Venus. One or both of Hesperus or Phosphorus would not have been Venus.
So it seems we are left with empirically discovered necessities.
This is a seperate point to that dealt with in my previous post. Yes, on this we agree.
Doesn't this just assert that an empirical judgement is contingent? WHere's the argument?
Quoting Mww
Well, we know 4=2+2, but that doesn't change over time... an we know water boils at 100?, at any given time; that doesn't change. So that doesn't work.
Quoting Mww
I did change that to "there is disagreement between Kant and Kripke", in an attempt to keep us out of court. Refresh issues.
Yep.
At the bottom of p. 178, the lectern is picked out using a demonstrative: "Here is a lectern".
Kripke asks if this lectern could have been made of ice. His answer is that it is entirely possible that the lectern before us is made of ice, but that if this were so it would be a different lectern.
(Edited to keep happy)
I don't see where he says the lectern before us could be made of ice. I think he's saying it couldn't be.
So it could be, but then it's not the lectern we're talking about right now.
We might have had before us a different lectern.
I don't see an issue, @frank.
Good thread. Got me to try Kripke again.
This is what you wrote:
Quoting Banno
That is incorrect. He doesn't say the lectern before us could be made of ice. You misquoted.
That seems unusually pedantic of you, Frank.
But I wrote that Kripke asks "could this lectern have been made of ice?"
I was wrong. Please forgive me. :roll:
I realize now I kind of went off on my own tangent in interpreting the whole text, which is different from the intent you've set out. I don't think you mind given the cheers, but I'm just noting it now.
Still reading along with the interpretations, though. Slow lab days these days post holidays :D
Here's the bit I take to count in our previous coinversation:
Do you wish to pursue this topic?
I'm not sure why you're getting miffed. I simply pointed out that you misquoted the text.
At this point, that is the substantive point I have to fucking make. OK?
So on to the top of p. 180, where we come across something that might be of further interest to @Mww.
That this table is not made of ice is known a posteriori - by examining the table. Yet that this table is not made of ice is a necessary fact about this table - if it were made of ice, it would not be this table.
We cannot know a priori if the table is made of ice or of wood. But given that it is not made of ice, it is necessarily not made of ice.
Yes, but let's move on.
If it was an interpretation, it was a misinterpretation.
No problem.
Is that a problem?
Correct. Not being made of ice is an essential property of the lectern. The basic idea here generalizes.
Wow!
I think I'm tempted by @unenlightened's approach. It's necessary, yet our language of logic is what makes it so more than what is the case. We can say what we like, and define what we like, and while that will change how we talk about things that won't change whatever "stuff" is.
He makes the point that what we're doing is epistemology. It's about truth.
And all of this sits within the scope of the deranged epitaphs. Someone could create a divergent use that undermines it, but even in undermining it they will be acknowledging it.
Just to make sure we'll hate one another, that last paragraph sounds Hegelian. ;)
But your first paragraph gots me rethinking the paper. Guess I'll have to read it more than one time. Shit! :D
Rude.
I agree that analytic propositions are necessarily true, independent of any empirical knowledge. For example, "all bodies are extended", as the notion of extended is implicit in the notion of body.
If we are given two analytic propositions "Hesperus is Phosphorus" and "Hesperus is not Phosphorus", how do we know which is true, if the truth of an analytic proposition is independent of any empirical knowledge ?
Kripke writes for any objects x and y:
(1) If x is identical to y, then if x has a certain property, so does y
(2) Every object is necessarily self-identical
(4) For every x and y, if x equals y, then, it is necessary that x equals y
Example one - let x by the Moon, and y be the Eiffel Tower
(1) If the Moon is identical to the Eiffel Tower, then if the Moon has a certain property, such as having a diameter of 3,476 km, so does the Eiffel Tower.
(4) For every x and y, if the Moon equals the Eiffel Tower, then, it is necessary that the Moon equals the Eiffel Tower.
Example two - let x be the object Hesperus, and y be an object that is not Hesperus
(1) If the object Hesperus is identical to an object that is not Hesperus, then if the object Hesperus has a certain property, then so does an object that is not Hesperus.
(4) For every x and y, if the object Hesperus equals the object that is not Hesperus, then it is necessary that the object Hesperus equals the object that is not Hesperus.
I may be misunderstanding, but I don't see any practical benefit to (1) and (4)
I hope this post isn't deleted as was my previous post for not being relevant to the OP.
If x and y are identical, that means x and y are two different names for the same object.
Like say John's nickname is Tweezer.
x is John
y is Tweezer
now plug that into the argument.
Taking x and y as proper names, whereby x is John, y is Tweezer. From (4), if John equals Tweezer, then it is necessary that John equals Tweezer.
But this is a logical implication, which says nothing about the reality of what is being expressed. I could say that if I lived on Mars, then I would open a pizzeria, or if I was a nuclear scientist then I would work on small modular reactors.
The possibilities are almost infinite. If John equals Bill Gates, then it is necessary that John equals Bill Gates, or if John equals Alison, then it is necessary that John equals Alison or if John equals the President of France, then it is necessary that John is the President of France, etc, etc.
We learn nothing significant from these logical implications, other than if two things are equal then they are necessarily equal, which seems a redundancy. Why not just say that two things are equal.
You're asking what earth shattering consequences follow from Leibniz's law. Kripke is just setting the stage to show off a contradiction. That's all. Keep going.
The first premise expressed at 180 ("given that it is not made of ice it is necessarily not made of ice") is a priori. It is directly derived from the law of identity, and a priori principles of "being" as described by Aristotle. When a thing comes into being, it is necessarily the thing which it is, rather than something else, as indicated by the law of identity. This a priori principle, along with the (empirically) given fact that a thing displays an order, is what leads us to conclude that the Form of the object necessarily preexists the material object.
The second premise, which supports the asserted "given", that the table is not made of ice, is a posteriori. The "given" that the table is not made of ice, is provided by empirical observation, therefore a posteriori.
The mistake which Kripke makes is to attribute to the conclusion the character of only one of the premises. One premise is a priori and the other is a posteriori, but he says the conclusion "it is necessary that the table not be made of ice", is a posteriori. Since the conclusion is stated as a necessity ("it is necessary that...") we must enquiry as to what validates this claim of necessity.
Kripke's conclusion is a mistake, because the necessity of the conclusion "it is necessary that..." is derived from the first premise which is a priori, "given that the table is not made of ice it is necessarily not made of ice". It is only the "given" aspect which is a posteriori, and the "given" is not at all necessary, and cannot provide the necessity required for the conclusion.. So it is very clear that the conclusion "it is necessary that..." is a priori, because the "given", or what is taken for granted (which is the a posteriori aspect of the argument), could be replaced with absolutely anything, Any possibility whatsoever, provided by empirical observation could replace "not made of ice", and the necessity of the conclusion would not be altered. We could still conclude "it is necessary that... (with the replacement empirical fact). Kripke simply employs smoke and mirrors sophistry, to make it appear like the conclusion "it is necessary that..." might be a posteriori.
No, Leibniz's Law states that if two objects have all the same properties, they are in fact one and the same.
My question is, why does Kripke need to add the word necessary to Leibniz's Law. What does "if two objects have all the same properties, they are in fact necessarily one and the same" add to "if two objects have all the same properties, they are in fact one and the same"
I'd say necessity is implicit in Leibniz's law. He's just making it explicit because he's about to challenge the notion that apriori=necessary, and aposteriori=contingent. He's going to show that there can be a statement that is known aposteriori, but is necessarily true.
Reformed analytic philosophers like Rorty will argue the opposite. Once we divest ourselves of our temptation to assume intrinsic features of the world, all we have is our changing performances of language as they simultaneously express and shape our material
interactions with each other. Formal logic and its various notions of truth depends for its sense on faith in intrinsicality. Even those at the very progressive edge of the analytic tradition, like Hilary Putnam, who is a conceptual relativist, hold onto a valuative realism
On the one hand, he argues So much about the identity relations between different categories of mathematical objects is conventional, that the picture of ourselves a describing a bunch of objects that are there "anyway" is in trouble from the start. what leads to "Platonizing" is yielding to the temptation to find mysterious entities which somehow guarantee or stand behind correct judgments of the reasonable and the unreasonable.
But then he insists there are intrinsic non-relative valuative grounds for scientific and ethical truth. This belief allows him to uphold ideas of warranted justification and truth.
Rorty , however , believes the following about warranted justification as it is used in formal logic:
The metaphysician thinks that there is an overriding intellectual duty to present arguments for one's controversial views - arguments which will start from relatively uncontroversial premises. The ironist thinks that such arguments - logical arguments - are all very well in their way, and useful as expository devices, but in the end not much more than ways of getting people to change their practices without admitting they have done so. The ironist's preferred form of argument is dialectical in the sense that she takes the unit of persuasion to be a vocabulary rather than a proposition. Her method is redescription rather than inference. Ironists specialize in redescribing ranges of obiects or events in partially neologistic jargon, in the hope of inciting people to adopt and extend that jargon. An ironist hopes that by the time she has finished using old words in new senses, not to mention introducing brand-new words, people will no longer ask questions phrased in the old words. So the ironist thinks of logic as ancillary to dialectic, whereas the metaphysician thinks of dialectic as a species of rhetoric, which in turn is a shoddy substitute for logic.
Rorty is just an ontological anti-realist. There's a whole spectrum of that including various hard and soft options. It's all analytical philosophy, though. If you want to read an article about it, it will be an analytical philosopher you're reading. Nothing particularly reformed about it, I don't think.
If you want to use logical shorthand, we have P = V, H = V, therefore P = H. Regardless, there was a time when it was a fact this thing in the sky was called P, and there was a time when it was a fact this thing in the sky was called H, and in these times, P was not known to be H. At some later time, experience informed that P, H and V were all the same thing in the sky, P = V at one time, H = V at a certain other time relative to the first time. After that, after the facts changed due to new experience, the thing in the sky was just V.
P never was equal to H, the proposition P is H never occurred to the Greeks, as Kripke said of something else and thus misspoke**, surely no amount of a priori ratiocination on their part could have conceivably made it possible for them to deduce P is H, so why are we belaboring the nonsense of it now?
** He said it of astronomers who discovered the distinction, when he should have said it of those who never considered there was one. Besides, one needs no a priori ratiocination when hes got a telescope and a camera.
Quoting Banno
Ehhhh ..maybe. Id say we have empirically discovered relations, the relations we understand as being so because they necessarily conform to the laws we invent to describe them.
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Quoting Banno
In the text, which as you must well know, is a convoluted mess, requiring some presuppositions, and wouldnt benefit this discussion.
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Quoting Banno
By knowledge is experience, the term knowledge is tacitly understood to be empirical knowledge. Mathematical propositions are not empirical knowledge in their construction, but only in their proofs. Mathematical propositions change over time only insofar as the system that constructs them changes; the human cognitive system that constructs mathematical propositions hasnt changed so the propositions wont change.
We knew once a liquid substance; we knew later a liquid substance we deemed to label water; we knew later the liquid substance we deemed to label water, boiled; we knew later water boiled at 100C, we knew later water boiled at different temps relative to pressure. Hell, we knew later, not only do things float in water, but water itself floats!!! How cool is that?? Knowledge changed over time.
We didnt know water boils at 100C at any given time, as you say, until we learned at one time water boils at 100C. We know post hoc and a priori, as mere inference, water under a certain set of conditions will always boil at 100C. Just like, because you put it there at one time, you know [i]a priori[/i ] that stupid cup is still in the stupid cupboard at any other time, as long as nothing happened to alter the initial conditions.
It is possible the set of conditions under which water boils at 100C changes, such that water no longer boils at 100C. Some would like to proffer that this is sufficient reason to claim physical law is tentative, and in so doing, imply human intelligence is schetchy at best, insofar as it is human intelligence alone which determines physical law. Which is tantamount to those some slapping themselves in the face, getting nothing from it but a ruddy cheek.
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Kant and Kripke. There is obvious disagreement, but they are doing different philosophies, so no big surprise there. The idea was probably, if Kant was brought into this era would he find current philosophy noteworthy. While it is patently unjustified to speak for him, personally I think he would find it unapologetically superficial, there isnt a particular philosophical doctrine these days a majority of thinkers support, and, theres a conspicuous dearth of cognitive metatheories.
Nowadays, people who philosophize at all are apt do so regarding whats said and its communal effect, rather than what is thought and its private effect, and his magnum opus concerned the rational subject over the empirical object, and even with the spectacular advances in physical science, the rational subject is still pretty much just as he was in the 18th century, so I think CPR would be written pretty much as it was. His other sciency stuff would probably be different, and theres reason to suppose he might have come up with stuff that set the tone for other scientists, just as he did on the 1700s.
Quoting Banno
All thats fine, but whats the point? That this table is made of this substance immediately precludes it being made of any other substance. I rather think that if this table is made of, say, wood, wood isnt so much an essential property, as being a given property. It would seem the essential property of a table is merely is spatial extension, its shape, without regard to the substance of its construction.
Of more import, methinks: Kripke says, this table, if it exists at all . If he talks of a table, isnt its existence given? Otherwise, shouldnt he be talking of a possible table? Minor quibble, one of many, and overall, irrelevant, other than to exemplify differences in philosophical ground.
Then he says, this table [s]if it exists art all[/s] was not made of ice is necessary . Taken as a complete sentence, shouldnt that have been was not made of ice is necessarily true? Continuing, and under the assumption he means necessarily true, he says, was not made of ice is necessarily true, it is certainly not something we know a priori.
Hmmmm ..I dont think thats quite right. Hes asking about what we know. So we have a thing we know, a table, made of something we know, say, wood, so we can say with certainty it is not made from anything else, but the ask concerns only what we know, not what we can say.
(Recall the quote, Experience no doubt teaches us that this or that object is constituted in such and such a manner, but not that it could not possibly exist otherwise )
Experience cannot tell us the table could not have been made of something else, but if it is necessarily true it couldnt have been made of anything else, because it isnt, we must have known that necessity a priori.
It isnt that we know it isnt made of ice, its that we know it is necessarily true it isnt made of ice. Given that there are only two ways for a human to know anything at all, experience and reason, and the former is from experience but the latter is not, therefore the knowledge in question must be from reason alone, which is, of course, a priori.
Im not going to apologize for the length of the post. Peruse or not as you wish.
Except that on one side are those who find the symbolism of logical formalism important, perhaps indispensable , because it gets at the root of all those things that are relevant to philosophy ( the nature of language, meaning , truth, justification ) and on the other those who find it not very useful and certainly not engaging with the fundamental issues of philosophy. They side with the later Wittgenstein who found formal
logic to get in the way of a clarified understanding of such fundamental issues. Would you call someone who had almost no use for formal logic , and thought truth was a confused idea an analytic philosopher? Even Putnam said analytic philosophy had reached the end of its relevance .
Necessity is being used in two different ways, between objects and between an object and its property.
Necessity between objects - between a lectern and a rostrum
As regards (4), necessity is being used between objects. He writes: "For every x and y, if x equals y, then, it is necessary that x equals y."
(1), (2) and (4) make use of Leibniz's Law, where "if two objects have all the same properties, they are in fact one and the same".
It seems to me that the use of the word necessary is redundant between objects, in that what does "if two objects have all the same properties, they are in fact necessarily one and the same" add to "if two objects have all the same properties, they are in fact one and the same"
Necessity between an object and its properties - between a lectern and its property wood
As regards the lectern, necessity is being used between an object and its properties, where he writes "So we have to say that though we cannot know a priori whether this table was made of ice or not, given that it is not made of ice, it is necessarily not made of ice.
As he persuasively argues, this lectern, if made of wood, is necessarily made of wood, because if not made of wood it would have been a different object, and it wouldn't have been this lectern.
However, necessity between objects is irrelevant to the question of necessity between an object and its properties. Therefore, necessity may be removed from (1), (2) and (4) without affecting his argument about necessity between an object and its property.
If someone described truth as a confused idea, I'd say they're not any kind of philosopher. Want to start a thread on it?
The necessity we're talking about is with regard to the truth of statements. Some statements are necessarily true, some are contingently true.
Note that I won't debate this with you. It's explained by Kripke in the essay, and that's the scope of his interests.
What if we are given one proposition, and its negation?
Quoting RussellA
Does it matter which, if there can be only one?
Quoting RussellA
The analycity resides in the relation of the conceptions. Doesnt matter if the conceptions are empirical. It is only after experience informs that P and H are in fact V, is it the case that all the conceptions which comprise V are found in both P and H, and it is necessarily true that either P or H represent V without any possible contradiction. The next step, then, says that there is nothing contained in the conception of P that does not belong to the conception of H, therefore, P and H are the same thing, or, that P is H is a necessarily true statement. We dont need the experience those conceptions represent, only that all of them are thought to co-exist equally in one object.
And here is the support for the claim that time is not a property of objects, which just might be the reason the whole shebang rears its head in the first place.
Tangled web and all, doncha know.
Why would anyone consider these analytic? They look to be synthetic.
Hesperus is the evening star; phosphorus, the morning star. It is not clear from the sense of these worlds that they are the very same thing.
Similarly, that Tully and Cicero are the same person is not analytic.
Well, one consequence is that, that x=y may be discovered empirically - examples are give - but has necessary implications. While this may seem obvious now, it is contrary to both Kant and Quine, fir different reasons. The notion that an empirical fact implies a necessary truth is one of the novelties of this paper.
Yep.
[math] P \supset \Box P[/math]
is invalid. It is certainly not as it stands a priori.
The whole point of the argument is that ?P in the case of the lectern is known a posteriori.
Edited: See [reply=Banno;769496]. 'In other words, if P is the statement that the lectern is not made of ice, one knows by a priori philosophical analysis, some conditional of the form "if P, then necessarily P".'
I don't think so.
It's more as if logic were embedded in a conditional... 'if you would talk in a coherent way, then you must follow these rules..."
Check out Gillian Russell's logical pluralism. Your argument might apply to logical monism, but that's not the only possibility.
Again, my take on the Kripke article is that this is a way of applying his formal method to natural languages, a way of approaching modality that avoids many issues, allowing us to talk in a coherent fashion.
One does not have to avoid contradiction, but since folk who do not avoid contradiction can say anything, their conversation is tedious, tending towards the tendentious.
So I'd prefer to talk to those who seek coherence.
Quoting Mww
I know water boils at 100? at normal pressure, as a result of experiments done at high school and reassurance from various authorities.
I don't know it a priori, nor by mere inference.
So I'm not following you at all here.
Length is fine, but you lost me early on.
[math](x)(y) [(x=y) \supset (Fx \supset Fy)[/math]
is not Leibniz's Law. That'd be something like
[math] UF(Fx \equiv Fy) \supset (x=y)[/math]
Not the same. I don't see that the argument (1-4) uses Leibniz's Law. (1) is the other way around, with the identify on the left of the hook.
A quick note that we need to keep clear when Kripke is talking about an identity that is established by a proper name and one that is established by a description, theory or predicate.
An identity established by a proper name is generally a rigid designator. Cicero is the very same individual in every possible world. Of course, he may not have been named Cicero, and someone else may have been named Cicero in his place, but keep in mind that these are modal facts about Cicero.
Demonstratives may act as rigid designators: this lectern may have been in the other room, but may not have been made of ice - since it is made of wood, if we suppose that it might have been made of ice, we would better say that this lectern might have been replaced by another, made of ice.
An identity established by a description is generally not a rigid designator. Hence the rejection of the description theory of proper names; a proper name is a rigid designator, hence it cannot be the very same as a definite description which is not a rigid designator.
It's clear from the examples given that statements of the form x=y can be discovered empirically, and hence at least some are not discovered a priori.
The alternative is that, as a result of some other considerations about necessity, some may suppose that all statements of the form x=y are necessary, and hence a priori (Is this @Mww's view?); and perhaps that only a very small number of expressions actually count as proper names (here I take Kripke to be referring to Russell's theory of descriptions, and hence perhaps @RussellA's view).
Krike's key argument here is that if one separates a priori/a posteriori on the one hand, from necessary/contingent on the other, one is not obligated to even enter into such discussions (top of p.181)
He goes on to again (indirectly) make use of the weaponised question - who is the sentence about? "Tully might not have been called "Cicero'" is a sentence about Tully; "Nixon might not have written the letter" is a sentence about Nixon. If names are rigid designators, there can be no question about identities being necessary.
But it doesn't follow that the identity is a priori.
(2) is Leibniz's law: A = A.
Quoting SEP
A=A is the Principle of Identity.
Could it have been made of a different kind of wood? Or of the same kind of wood from a different tree? Or different planks from the same tree?
Oh. I thought that was Leibniz's law.
Kripke calls (1) the law of the substitutivity of identity.
Didn't Kripke mention Leibniz's law? Although I've thought A=A was Leibniz's law since I read a book about him. Don't know how I got that confused.
I take him here to be saying that the argument (1-4) applies when a and b are proper names and F a property.
Yes, you're right.
At its initial inception, and the ground of all others, A = A is one of Aristotles three logical laws of rational thought, this particular one found in Prior Analytics, 2, 22, 68. Whatever Leibniz or any others did with it, follows from that.
For what its worth .
Yeah, I feel ya, bruh. When I see ?F(Fx ? Fy) ? x=y. my eyes just sorta glaze over, mind goes blank, reason goes ..say what????
Like I explained, there are two premises stated by Kripke, #1 "given that it is not made of ice it is necessarily not made of ice", and #2, through "empirical investigation" we know it is not made of ice. From these two premises he makes his conclusion that it is known a posteriori "that it is necessary that the table not be made of ice". Premise #1 is a priori, and premise #2 is "given" through empirical observation, therefore a posterior.
#1 is stated as a premise, not as a conclusion, so whether or not it is valid is not in question. We might investigate its soundness though. It is derived from the law of identity, that a thing is what it is, and cannot not be what it is. It is an a priori principle based in intuition, and it is not meant to be a valid conclusion From this Kripke derives the necessity required for the first premise "given that it is not made of ice it is necessarily not made of ice".
And from that necessity stated in that first premise, the a priori premise, he derives the necessity of the conclusion ""that it is necessary that the table not be made of ice". His mistake is that he characterizes this as an a posteriori principle, when the necessity stated in the conclusion is derived from the a priori premise, rather than from the a posteriori premise.
Quoting Banno
This is incorrect, and is the result of Kripke's mistaken conclusion that the "necessity" of identity is a posteriori. That's wrong, as described above. The necessity of such statements is derived from the law of identity, that a thing is necessarily the same as itself, and cannot be other than itself, which is a priori, and not discovered empirically. Premise #2 above, that the thing is what it is named to be (wood and not ice), is a posteriori. But there is no necessity in that premise. Therefore the necessity of statements like "x=y" cannot be accounted for by empirical discovery. Empirical discovery does not provide the required necessity, which is only provided by the a priori principle of identity.
Read my last two posts. That the lectern is made of wood, and not made of ice is given empirically. But the empirical observations do not provide the necessity required to say that it is necessary that the lectern is made of wood and not of ice. The necessity is derived from the a priori law of identity, which implies that it is necessary that a thing is what it is, and not something else.
So, the fact that the lectern is made of wood, and not made of ice, is supported by the empirical observations. But empirical observations do not make it necessary that the lectern is made of wood and not ice. The necessity, (that it is necessary that the lectern is wooden and not made of ice), is derived from the a priori law of identity, which states that a thing cannot be other than it is.
A = A is central to Leibniz's project, although I've dropped a lot of that in the bit bucket apparently.
Well, no, since as you will have noted, he gives examples where this is not the case.
Yeah it is.
You claimed:
Quoting Metaphysician Undercover (my bolding)
It isn't. It is invalid, so it can't be a priori. If it is true, it is true a posteriori, as Kripke uses it.
I gather that you are thinking something like that 100? just is the boiling point of water, by definition?
I thin that's the sort of thing in the next part of the paper, so maybe tomorrow.
Whole bunch of caveats before this is Mwws view, first being, even assuming linguistic liberties in the original, no statement in itself is ever necessary in the domain of pure logic, to which the very idea of necessity solely belongs.
Second being, only x = x is necessarily true under any possible conditions, and that because the god Aristotle said so, and proved it in his way in his time.
Third, that x = x is necessarily true under any conditions because Aristotle said so, yet that truth is an a priori judgement, or cognition, is because the god Kant said so and proved it in his way in his time, as an extension of Aristotles law not addressed by him.
OK, so we got x = y. X is a dog, y is a mammal. It turns out it is necessarily true a dog is a mammal, even though a mammal is not necessarily a dog which an equality implies, so the formula holds in one direction but not in the other.
Staying with x = y, but this time x is a dog but y is a can of green beans. Here, it is absurd that a dog is a can of green beans. Why put rational trust in a logical construct that doesnt hold under any conditions, which must include its own inversion? If it depends exclusively on what x and y are, such that x and y are somehow predetermined as connected to each other, how can a universal logical truth such as x = y be built on it?
And to cap it all off .that a series of square, diamond and oddball symbology will make it so, where a series of words wont?
Way past my bedtime
It is an a priori principle called "the law of identity". The law of identity implies that a thing is necessarily what it is, and not something else. It is used by Kripke in the first premise "If the table is not made of ice, it is necessarily not made of ice". That is an a priori principle. Whether it is true, false, valid, or invalid, is not what is at issue. What is relevant is that it is an a priori principle necessary for the conclusion produced "It is necessary that the table not be made of ice".
Notice he states "and this conclusion is known a posteriori, since one of the premises on which it is based is a posteriori". That mentioned a posteriori premise is what is derived from empirical investigation. It is stated as "The table is not made of ice". The other required premise, "if the table is not made of ice it is necessarily not made of ice", is a priori.
Therefore his claim, "this conclusion is known a posteriori" is not justified by his argument.
Not even x=x?
Quoting Mww
Hu?
Quoting Mww
Ah. That's a different "is". I found myself pointing this out the other day...
Quoting Banno
Dogs are mammals is an example of F(S)-type "is". The "=" means that the thing on the left is the very same as the thing on the right. dog=mammal appears ill-formed.
Those diamonds and boxes and other oddball symbology serve us well in avoiding such misunderstandings.
[math] P \supset \Box P[/math]
is not an instance of the law of identify.
I'll leave you to it, Meta. Not interested in playing your game.
[math](1)\,(x)(y) [(x=y) \supset (Fx \supset Fy][/math]
Seems it would be worthwhile going over some of the "oddball symbology".
(x) is just "for all x".
(x=y) says that x and y are the same thing; they are co-referential. If you need more information, check out this Stanford Introduction to Logic page.
The hook is just material implication.
The F is capitalised, as opposed to a propositional variable, f. I take this as marking it as available for broader substations, like the substitution of (2) into (1) that gives (3)... yep, hope you noticed that. Kripke took out the F and replaced it with ?(x=x), and with ?(x=y), since they are the same thing...
(4) derives from of (3) by removing the ?(x=x), since it is always true, since it is a logical law.
It is now, after the discovery of it. That water boils at 100C is known a priori only by those after having immediate experience, re: those that test for it, or mediate experience, re: those that learn of the test for it. Its irrelevant that water always had a specific boiling point, as long as no one knew what it was.
. Mathematics and physics are the two theoretical sciences which have to determine their objects à priori. The former is purely à priori, the latter is partially so, but is also dependent on other sources of cognition .
With respect to the theoretical science of the boiling point of water, the aspect partially a priori, to determine their objects a priori is to think how to find out the boiling point of water, to ask oneself, when does water boil, how do I find out, and herein dependent on other sources of cognition refers to the observation, hence the phenomenon, that water does in fact behave in a certain way given certain conditions. Somebody, somewhere sometime saw water boiling and wondered how hot it had to be to act like that, all a priori, even if under empirical conditions.
As I mentioned, this is one of the things in Kripke I took exception to, in that he said the astronomers that figured out P and H were one and the same couldnt have done it by means of a priori ratiocination, when in fact, it was the only way they could have done it. No different than finding out water boils at 100C.
Cool. Interesting. Thanks.
Question: why drop out the part known to be true?
Say there is a law. To remove something that makes it a law, is it legitimate to still call it a law?
If there is a certain undeniable truth already given, and it is deleted .dropped out ..how does that not go to great length to falsify the product of whatever formally contained it?
The whole thing begins with ..for any two objects x and y, if x has these properties and y has these same properties, then x is the same as y. Sounds rather obvious, at first, and just the words themselves are sufficient to call it a true statement, insofar as these words, taken by themselves, dont contradict themselves.
This must be why Kripke dropped out the F, insofar as it is impossible for every property F to belong to both x and y simultaneously such that x = y. If it were possible, then x =x is false, but it is already an established necessary truth that x = x and cannot be both true and false.
I think one needs be no more than a low-level logician to understand that dropping out both a logical necessary truth and an empirical impossibility, are both required in order to sustain the ideas behind the article.
So .ok, two questions .can the article still have any meaning if those two dropped-out conditions are left in?
quote="Banno;767932"]Those diamonds and boxes and other oddball symbology serve us well in avoiding such misunderstandings.[/quote]
.or creating them?
Thanks for the clarification for is and =s.
Quoting Banno
Quoting Mww
Kripke wrote: "To state finally what I think, as opposed to what seems to be the case, or what others think, I think that in both cases, the case of names and the case of the theoretical identifications, the identity statements are necessary and not contingent."
If "Hesperus" is "Phosphorus", then "Hesperus" is of necessity "Phosphorus", but Hesperus is not necessarily Phosphorus
I will use the practice that "Hesperus" is a name in language and either refers to or is described by its properties such as "bright", "visible", "ringless". Hesperus is an object in the world and is its set of properties bright, visible, ringless.
My belief is that Hesperus has no existence over and above its set of properties, in that, if all the properties were removed, then there would be no object, as argued by FH Bradley.
There are two identity statements to consider, "Hesperus is Phosphorus" and Hesperus is Phosphorus.
Analytic propositions
The statement "bachelors are unmarried" is an analytic proposition that is true solely by virtue of its meaning. As it is true by definition, its truth is a priori. As Kripke argues that this lectern made of wood is necessarily made of wood, a bachelor is necessarily unmarried. The meaning of words is determined by social institutions, and are codified either in dictionaries or similar or in daily use, as Wittgenstein proposed.
Empirical Observations
John and Mary observe an object first in position A and then later in position B. John believes the body moves smoothly from A to B. Mary believes the body moves in a series of jumps from A to B. It is empirically impossible to determine who is correct, as we can only infer what happens between A and B, from Hume's constant conjunction.
Axioms
If John is in the majority opinion within his society, the social institutions may codify the concept that well-behaved objects move smoothly between two points as an axiom, as the axiom of "spatio-temporal continuity". Axioms are regarded as being established, accepted or self-evidently true, as with Newton's Laws of Motion. However, it is in the nature of axioms that the axiom of "spatio-temporal continuity" may or may not be true, in the sense of corresponding with facts in the world.
In fact, if an object was observed to jump through space-time, by definition it wouldn't be a "well-behaved object". As the axiom of spatio-temporal continuity is true independent of any empirical observation, it is an analytic proposition, its truth is a priori, and well-behaved objects by definition necessarily pass smoothly through space-time.
"Phosphorus" is necessarily "Hesperus"
Phosphorus and Hesperus are objects. Phosphorus is observed as an object in the east, is named "Phosphorus". and Hesperus as an object in the west, is named "Hesperus". From the axiom of spatio-temporal continuity, and under the assumption that "Phosphorus" and "Hesperus" are well-behaved objects, moving smoothly from the east to the west, it may be concluded that "Phosphorus" and "Hesperus" is the same object, the same Planet. Note that "Phosphorus" exists in language, not in the world. For convenience this single object may be named "Venus"
If when observing the sky, what was thought to be "Hesperus" was observed not to be moving smoothly, then by definition it couldn't be "Hesperus" but must be another object.
Two possible identity statements
As the identity statement "Hesperus" is "Phosphorus is based on the assumption that both "Hesperus" and "Phosphorus" are well-behaved objects, and as well-behaved objects necessarily follow the axiom of spatio-temporal continuity, then the identity statement "Hesperus is Phosphorus" is necessarily true.
However, as it is impossible to empirically determine that when an object in the world has moved from one position to another that there have been no jumps, it cannot be proved that Hesperus is Phosphorus, meaning that the identity statement Hesperus is Phosphorus is not necessarily true.
I suppose I must stop now. All the very best to everyone in the New Year, whichever part of the world you are in. :smile:
I searched through the essay and could not find any examples which deal with just what criteria we could possibly have for deciding whether it should be thought of as the same lectern in counterfactual scenarios. The way I see it, since nothing is separable for everything else, the identity of an object is its entire history up the present and none of that could be changed without losing its identity.
Because implication is transitive:
If A?[B?C] and B is a theorem, or true, then A?C.
In
[math](3)\,(x)(y) (x=y) \supset [ \Box (x=x) \supset \Box [(x=y)] [/math]
(x)(y) (x=y) is A, ?(x=x) is B, and ?(x=y) is C. Hence
[math]\\ (4)\,(x)(y) [(x=y) \supset \Box [(x=y)][/math]
I find your puzzlement, puzzling.
Good for you.
Kripke argues otherwise, and his argument is widely accepted, and this is a thread about his argument.
That is, the thread is about what Kripke believes, and not so much about what you believe.
I think that article indirectly addresses your argument, and finds it wanting. In particular, I think one might wield what I've called the weaponised question. That is, what is it that the sentence quoted above is about? It seems that it is about Hesperus. If one asks what it is that you are suggesting we remove the properties from, the answer is "Hesperus", and this is so even if the properties are removed.
That is, in Kripke's terms "Hesperus" is a rigid designator, while it's various properties may not be.
That's a different point, and I agree, and I note that the lectern example is I think not repeated in Naming and Necessity.
We have the contingent "This lectern may have been in the other room", and we have the necessary "This lectern may not have been made of ice", and the question is, why is one contingent yet the other necessary?
I take the answer to be that the demonstrative "This lectern" is such that the lectern could have been in the other room but could not have been made of ice; that "this lectern" has the sense "This wooden lectern", giving us "This wooden lectern could have been in the other room" and "This wooden lectern could not have been made of ice".
But I wonder if the lack of clarity here is what led Kripke to drop the example.
Quoting Janus
Then I take it you are agreeing with Quine that modal utterances have no sense.
Fair enough. That kinda ends the discussion. Thanks for you contribution.
The first is that folk mix two different ways of talking. This is the De re/de dicto stuff again, but as I said previously, putting it in those terms often doesn't seem to help. It's clear our words may have had different meanings, that for example we might have had "5" where 4 is, and found ourselves writing "2+2=5" and saying that it is true. That's certainly possible.
But as Kripke says, this is not what we want. Rather, given how we do indeed use the words, 2+2 could not be equal to 5. "We want to use the statement in our way and see if it could have been false".
Something along these lines might be what troubles when he suggests Quoting Mww
If we set "100?" as another term for "the boiling point of water", if they equal the very same thing in the way 2+2 equals 4, then in any possible world, the boiling point of water would be 100?. And since that's our definition, then Mww would be correct that the boiling point of water is, a priori, that is, from the nature of the very terms used, 100?.
Then what Mww says would be understandable.
But what we did was to take the temperature at which water boils, and call that temperature 100?. We set 100? as a rigid designation, so that it refers to the very same temperature, regardless of what temperature water boils at. We fix the referent of 100? by setting it to the temperature at which we find water boils; but once this is done, we can use it to refer to that very temperature even if water were to boil at a different temperature. We go past the boiling of the water and fix 100? to the temperature.
Similarly, we might fix "Tully" as the Roman orator who denounced Cataline, but once this is done, we might discover that Tully did not in fact denounce Cataline. In such a circumstance, we would be making a discovery about Tully. Once we fix the reference of "Tully" using "the Roman orator who denounced Cataline", we can refer to Tully without making use of that description.
As am I, but then I think Kripke showed his view to be misguided. Seems to me that counterfactual sentences make sense. After all, you might not have agreed with Quine...
I'd say that if I do indeed agree with him right now, then it is not the case that I might not have agreed with him right now, because that would mean comprehensively changing the way I presently think. On the other hand I might not have agreed with him in the past, or I might not agree with him in the future, but neither of those possible scenarios would be counterfactuals, as far as I can tell.
And that's not something we might consider?
:wink:
Well it is, but then it could not happen right now, as I currently think just the way I do; it would take time. But then as I say, if I later changed my standpoint, it would not be a counterfactual scenario, but a change in the factual.
But this seems to raise the question as to whether there are various possibilities as to how my life will unfold, and of course, from the epistemological and the logical points of view, there are. But are there really?
That, I would say, is unknowable; which seems to mean we are not entitled to an opinion on that question. I also think we have to acknowledge that the granting of alternative future possibilities is only relative to the limited context of what we know and what we can imagine.
This is where Platonic idealism misleads us into nonsense. Temperature scales relate numbers to the physical world. That there are numerous different temperature scales based in different principles for making such a relationship demonstrates that this is the case. The idea that we "fix 100? to the temperature" implies that there is something independent from the scale and its relationship to the physical world, an independent "ideal" called "the temperature", which "100?" actually refers to.
Clearly this is false because there is nothing independent of physical things designated to be 100? that we could point at and say this is what "100?" refers to. So to say that there is a thing called "a temperature" which "100?" refers to is just a creative fiction, produced to facilitate communication.
This is the reason why Platonic idealism misleads us so easily, because it is so effective at facilitating communication. For example, instead of having to demonstrate what the numeral "2" means in each instance of usage, we assume an independent ideal, "a number" as a named thing which that numeral refers to, and this makes the use of "2" much easier.
The assumption of real ideals, as real objects which exist independently of the context of actual usage of the symbols, presents an ontological problem. This problem truly exposes itself when we try to determine what type of existence these supposedly named things, ideals, actually have. That problem was well demonstrated by Plato.
Quoting Banno
So, this issue is not as simple as you make it out to be. As discussed in another thread, the boiling point of water is equally a function of pressure, as it is temperature. Therefore we cannot correctly claim that "in any possible world, the boiling point of water would be 100?". This mode of speaking is just facilitated by your Platonic idealism, which assumes an independent object called "the temperature". This makes temperature an object rather than a property, which is a category mistake.
Then we still have the further ontological mistake made by Kripke, which is the proposition that an object designated by a "rigid designator" could be the same object in a multitude of possible worlds, despite having different properties. Kripke's work is just riddled with ontological mistakes, one after the other, and it is highly questionable as to what his intent actually was..
My fault; Im not up on the subtleties.
I mean .whats the point in having identity, giving it absolute power as an irreducible necessity, then say it can have substitutivity attributable to it? Makes no friggin sense to me. From which follows, of course, x = y becomes a metaphysical abomination.
It's just a way of talking.
Thou shalt have no other gods before me?
Well, that made me laugh.
And then
This, very much contra Russell, Searle, and many, many others.
A description may be used to pick out some individual in order to give it a name. But thereafter, the name can be, and Kripke claims, is, used to pick out that individual without using the description. And again the argument is the weaponised question: What is the sentence about? Suppose that we use "the man who denounced Cataline" to pick out Tully. It make sense to then ask, who is the sentence "Tully might not have denounced Cataline" about? And it is clear that it is about Tully. That is, "Tully" refers to Tully, even in the counterfactual case that Tully did not denounce Cataline.
This was one of a number of arguments from around that period that pretty much put an end to the description theory of proper names.
Just to be clear, the idea of the "weaponised question" is my way of presenting Kripke's argument. It fits with my view that what is often most important in a philosopher's writings are the tools they provide that have a more general use. That is, perhaps the most valuable lesson in this article is to learn to ask critically, "What is the sentence about?"
It's the things to which, in a formal system, the individual variables a,b,c... refer.
Im not even going to ask how you did that.
Must suck to have to stop and teach the preliminaries before you can get to what you want to talk about.
This would only work for those who already know the individual being referred to by name. This requires context, which is established by description; so it seems rigid designation is always underpinned by implicit description, even in cases where no explicit description is required. The only way around that would be to have just one unique name for every individual, but that would be enormously cumbersome.
Would it help you if I preceded every post with "I might be wrong, but..."?
For me, the all are.
That was my Honours thesis. It's wrong.
Trouble is, as I think Donellan pointed out, we can use proper names correctly even when we do not have a suitable definite description.
Hence there need be no implied definite description. Proper names just refer.
I'm still here. Nothing really to add at the moment.
I'm more interested in consistency across possible worlds, as people get hung up on this.
Quoting Banno
Maybe it's off topic for this thread, but how would you say that "100?" refers to a thing called "the temperature" if not by invoking Platonism?
Quoting Banno
In your interpretation of Kripke does the thing referred to with "100?" qualify as an individual? If not, then how does "100?" become a rigid designator for you, naming the very same thing in all possible worlds?
The problem obviously, is that "100?" is a description, and only by Platonist ontology does this descriptive term refer to an object. Likewise, only by Platonist ontology can we say that the descriptive term "2" refers to a thing called a number.
Happy New Year!
Nice job managing these threads lately! I'm taking notes on that for months down the road when I'll have more time. :wink:
For now, I'll just read... time permitting.
And you.
See . You might be interested.
Cheers.
Using a name without knowing what it refers to is not intelligent usage; it would be as significant as a parrot being able to use a name.
Not particularly. Ill just do my own thing, try to keep up.
It's a good read, if you can get a hold of it.
I might set replying to as the assignment for this unit...
Looking forward to that one. I don't have much to say hereabouts.
Wait a minute. You didn't understand Kripke when we started. Why are you trying to assign shit?
Oooo always wanted to be in a unit.
You said unit.
Sorry, Frank. Dunno what that means.
Im a virgoyankeebabyboomer with no sense of humor.
The next bit is about heat, so we finally get to 's post.
We might have had the sensation of heat without the motion of molecules...?
Seems to me a shame that the focus here is an the sensation.
Thanks Banno, but that doesn't really solve the problems.
The way I see it, Kripke has no respect for the difference between a logical subject and a physical object. The former can exist in many possible worlds, the latter, by the law of identity cannot. So a rigid designator (designating the same thing in every possible world) could refer to a logical subject, but it cannot refer to a physical object. Treating the logical subject as if it were an object is Platonism. And once Platonist principles are employed, failing to distinguish between the material object and the immaterial object results in ontological confusion, as well as a compromised epistemology.
I'm a virgoaussiebabyboomer, with some kind of sense of humour, and I don't know what it means either...
edit: (dirty, perverse and/or absurdist)
Ahhh another one of the cool kids.
Best I could do was a Beavis and Butthead reference.
I'll see your Beavis and Butthead and raise you a Rick and Morty. :nerd:
Pass. MUs mindset is closer to mine than Kripkes.
Still, Kripke does say hes not considering the ontological side of existences in possible worlds. Which, to me, just says a possible world is this one under a completely different set of conditions. But then, the setters of those designators wouldnt be here to set them, and theres no warrant to say that possible world would have the means to set its own designators, so ..vicious circle.
But, Ive recently discovered theres a logic for that.
Well, mightn't it?
Does temperature equate to molecular kinetic energy?
well,
Temperature is a physical phenomena; in a gas it's directly related to the RMS average velocity of the molecules involved (contra ).
So yes, it is necessarily the case that temperature equates to molecular kinetic energy.
But does temperature equate to (the sensation of) heat?
Kripke gives a few examples to the contrary. If I have understood aright, he is arguing that, that we feel molecular kinetic energy as heat is a contingent fact about us, and might have been otherwise. He provokes the difficult argument that it is necessary that heat is molecular kinetic energy, but contingent that we happen to feel this as the sensation we call heat.
Quoting Moliere
Well, I think it is. That is, I'm now reading Kripke as suggesting that heat and the sensation of heat are somehow different things. Not too sure about that.
Cannot. Sensation consists - in part at least - of biological machinery, whereas temperature needs none.
Seems so.
Not contra MU, you mean exactly as I said. We "relate numbers to the physical world", and come up with what you say here, "average velocity". Temperature is a measurement, the result of applying a scale, it is not the thing measured.
What I asked is how you support your claim that the value of 100? is fixed to something called "the temperature", without invoking Platonism. That we move on, from fixing "100?" to the boiling point of water, to fixing it to some other physical activity like the average velocity of molecules in some substance, does not support your claim that 100? is fixed to "the temperature".
Quoting Banno
So you continue with a misrepresentation, in the attempt to reify "temperature". Temperature is the number assigned, based on a scale of measurement, it is not the activity itself, which is more properly called heat. So we cannot say that one is equivalent to the other. That would be a category error, like saying two chairs are equivalent to the number two.
Molecular motion is an example of heat, as is infrared radiation, but neither can be said to be equivalent to temperature, because the temperature scale must be capable of measuring all forms of heat. The temperature of something is a number produced by measurement, the application of a scale. And "temperature" in general may refer to that scale, but it does not refer to the property which is measured, heat and lack of it (cold).
This is a good place for the analogy of the map and the terrain. When we take the temperature of something and say that it has a temperature of 100?, it might be the activity of molecules which is being measured, but the temperature,100?, is the measurement. One is the terrain, the other the representation (map). To interpret the representation "100?" we must refer to some rules, just like we have to refer to the legend when interpreting the map.
For a thermometer, or some sort of mechanical probe, seems so. For the human skin, its sensation is of more or less heat, or heat or no heat, temperature, as representation of a specific degree of heat relative to a standard, being irrelevant.
[quote=pdf, page 10]
So, in this sense, the expression 'the inventor of bifocals' is nonrigid: under certain circumstances one man would have been the inventor of bifocals; under other circumstances, another one would have[/quote]
[quote=pdf, page 11]
What do I mean by 'rigid designator'? I mean a term that designates the same object in all possible worlds[/quote]
!!!
This one has turned all about in my mind.
So the property of necessary self-identity -- even if the object does not exist, the object is necessarily self-identical, that is, self-identical in all possible worlds -- is kind of trippy.
I'm wondering what on earth an object is at this point, other than somehow distinguishable from statements given Kripke's previous distinction.
Quoting Banno
I'm good with distinguishing the sensation of heat from heat, even if Kripke doesn't. At least, a lot of my hesitation I think comes from knowing enough about heat to say it's a conceptual web that's slippery, if what we're trying to do is philosophy.
So my preferred notion of heat is "that which a thermometer measures". And I'm fine with a certain amount of loose use of "thermometer" (like, thermocouples and mercury thermometers are measuring the same thing).
And, from that, we can specify many ways of talking about heat.
One way is the kinetic theory, which is apt in the case of gasses at particular Pressure-Volume ranges we commonly interact with.
"molecular motion", however, would not pick out the very same atom in all possible worlds. It doesn't refer to any particular atom. It's an aggregate property.
So I suppose I'd have to say -- if molecular motion is a rigid designator, then it's at least picking out an unintuitive object -- a collection of particles that could have been different particles (and yet retained the same aggregate properties, i.e., it could be composed of oxygen atoms that come from Venus and still have the same properties) and yet is the same aggregate in all possible worlds.
This puts X into the realm of possibility, and leaves X as possibly referring to an object, and possible not. This is where X needs to be if it is going to be the same in every possible world. That puts the judgement as to whether X corresponds to an actual object, and the important judgement as to which possible world corresponds with a presumed actual world, into a completely different category, i.e. a completely different type of judgement.
Under Kripke's plan, whereby X, as a rigid designator, represents the same object in every possible world, we have no real principles whereby we can separate the correct possible world (the one which best corresponds with the real world), and all the other possible worlds, because the real (actual) object is designated as within the possibility. This is because he does not allow for a separate real object, which we might compare the possible worlds to. The object is always as it is described in its possible world, but at the same time, the same object is in all possible worlds. This leaves no room for the real object, in a real separate world because the real object is designated as being within all possible worlds.
Those premises result in a dichotomy of Platonic realism, and anti-realism. It gives us the choice of those two ontologies. Either the real object is the very same thing as the logical subject (Platonism), having real existence in all possible worlds, or else we deny the reality of Kripke's "object", and say that the rigid designator does not reference a real object, only a possible object, but then we are left with anti-realism.
In other words, Kripke hands us the metaphorical "have you quit beating your wife?". If we affirm his premises, and accept the "object" indicated by the rigid designator, we are plunged necessarily into Platonism. If we deny the premise, saying that this is not a true object, we proceed into anti-realism, because there are no principles provided for any real object, and we are denying the reality Kripke's proposed "object". Therefore the correct response is to reject his premises altogether, as some sort of trickery, or at best, as simply incoherent.
I agree that "Hesperus" will continue to exist in language as a rigid designator even if all the properties of Hesperus disappeared from the world.
I will use the nomenclature that "Hesperus" exists in language and Hesperus exists in the world.
"Hesperus" may exist in language even if it doesn't exist in the world
1) Hesperus as an object in the world has millions of properties, most of which are unknown, but includes properties such as being 12,103km in diameter, having a solar year of 117 Earth days, has a central iron core, has a rocky mantle and has an atmosphere 96% carbon dioxide, 3% nitrogen, etc.
2) Hesperus has been named "Hesperus". If all the properties of Hesperus disappeared from existence, Hesperus would no longer exist. There is no example of an object existing in the world that doesn't have any properties. However, "Hesperus" would still exist in language. For a word in language to have meaning, it must have a set of properties, such as "being 12,103km in diameter", "having a solar year of 117 Earth days", etc. No word in language has meaning if it has no properties, for example a word such as "xxyyxx".
Nixon may be named "Nixon".
Similarly, Richard Nixon as an object in the world has millions of properties, most of which are unknown, such as born in 1913, family home in California, attended Whittier College, had a spot on his lung, a good debater, enthusiastic, etc. There are different approaches to how Nixon is named "Nixon".
1) For Ruth Barcan Marcus, proper names are tags which refer to an object which is the bearer of the name. Tags are directly referential and without descriptive content. For example, in the morning Nixon is tagged "Nixon". The tag could be a blue cross or a sheet of paper with the word "Nixon" on it. In the evening, the person with the tag is by definition "Nixon", even though the person may in fact be George McGovern.
2) For Bertrand Russell, in the morning Nixon is described as "born in 1913", "attended Whittier College" and "a good debater", Such a description, such a cluster of properties, is judged sufficient to pick out an individual uniquely. In the evening, the person that can be described as "born in 1913", "attended Whittier College", "a good debater" is by definition "Nixon", even though in fact it could be George Elmer Outland.
3) For Kripke, from (1), page 163, x may be identical to y and x may have the property F. For "Nixon" to be a rigid designator, for "Nixon" to be "Nixon" in all possible worlds, "Nixon" must have essential properties, such as having a spot on his lung. As with the example of the lectern, a non-essential property could be being in a different room. Whether a property is essential or non-essential can only be determined by human judgement, and then codified by social institutions, either fixed in a dictionary or similar or by daily use. For "Nixon" to be "Nixon" in all possible worlds, "Nixon" must have essential properties, such as having a spot on his lungs, where the property having a spot on his lungs is one designator of "Nixon", and as fixed in all possible worlds, is a fixed designator.
"Unicorns" exist in language and may or may not exist in the world.
1) I can define a "standard weight" as having the property 12.102kg, even before ever knowing whether or not 12.102kg exists in the world. Having the property 12.102 kg is an essential property of a "standard weight", is true in all possible worlds, and is a rigid designation. If I subsequently discover 12.102kg in the world a posteriori, I know a priori that it is a "standard weight", in that having the property 12.102kg is a necessary property of a "standard weight".
2) I can define a "unicorn" as having the properties the body of a horse and a single horn in its forehead even before ever knowing that unicorns exist in the world. Having the properties the body of a horse and a single horn in its forehead are essential properties of a "unicorn", and is true in all possible worlds as a rigid designation. If I subsequently discover in the world a posteriori the body of a horse with a single horn in its forehead a posteriori, I know a priori that this is a "unicorn", as having the body of a horse with a single horn in its forehead are necessary properties of a "unicorn".
Kripke's proposition that "identity statements are necessary" is true
1) Objects are observed in the sky. By observation, as "Phosphorus" has a diameter of 12,103km, and as "Hesperus" has a diameter of 12,103km, "Phosphorus" is identical in diameter to "Hesperus". Therefore, the identity statement "Phosphorus is identical in diameter to Hesperus" is true.
2) The property being visible is a priori defined as non-essential, and the property of diameter is a priori defined as essential. As "Phosphorus" has a diameter of 12,103km, having a diameter of 12,103km is a necessary property of "Phosphorus". As "Hesperus" has a diameter of 12,103km, having a diameter of 12,103km is a necessary property of "Hesperus". As "Phosphorus" has of necessity a diameter of 12,103km, and as "Hesperus" has of necessity a diameter of 12,103km, "Phosphorus" is of necessity identical in diameter to "Hesperus". Therefore, the identity statement "Phosphorus is identical in diameter to Hesperus" is necessarily true.
What do you make of this, pg 177-8:
One could not say that though in fact every even number is the sum of two primes, there could not have been some extra number which was even and not the sum of two primes. So we certainly do not know, a priori or even posteriori, that every even number is the sum of two primes.
Yep. More or less. Misusing "begs the question", Professor Dave Explains...
But, see also...
Quoting Banno
...but it wouldn't make sense if it were otherwise...
So in some possible world, Hesperus has no properties, and hence Hesperus does not exist in that world.
It doesn't follow that Hesperus does not exist in some other possible world.
The domain of discourse includes Hesperus - Hesperus is one of the things we can talk about. That domain of discourse has within its scope multiple possible worlds, some of which include Hesperus, others of which do not. But in all those possible worlds, Hesperus is Hesperus.
Lots of other issues. Let's stick to one at a time.
At stake is no more than our choice in parsing a sentence.
In the case of the demonstrative, "This lectern might not have been wood" can be understood in two ways. On the one account, this wooden lectern might have ben replaced by some other lectern, which was not made of wood. On the other account, this very wooden lectern might not be made of wood, and an inconsistency occurs, since we would have a wooden lectern that was not made of wood.
So the first is the better option. The demonstrative rigidly designates the lectern.
In the case of proper names, the name rigidly designates the individual. Cicero is necessarily Tully, and any properties that are attributable to one are attributable to the other. Of course Cicero might have not had that name, and might have done different things, but in such cases Tully would also have had a different name and done different things.
And, Kripke supposes, this goes for any equivalence between heat and the motion of molecules. If "heat" is a rigid designator for that sensation, and "the motion of molecules" is a rigid designator for molecules in motion, then if heat is the motion of molecules, it is necessarily so.
There are all sorts of issues wrapped up in this last. Not the least is the underlying assumption that there is the one sensation that is felt by each and every one of us when we feel heat. Now I do not think this is quite right, and hence I do not think this example is comparable to that of Cicero nor the lectern.
And I think this issue carries over to the next consideration in the article, mind-body dualism.
That's not what he said.
Quoting Banno
No, it doesn't. As he explains in the passage you quoted, it doesn't even make sense to say the lectern could have been made of ice. It's not even imaginable.
This is a similar issue which I went over with Banno already, concerning Kripke's premise that if the table is not made of ice it is necessarily not made of ice. That premise is a priori. And in your example, we need a similar a priori principle which states that one measurement of 12,103km is necessarily the same as another measurement of 12,103km. Kripke easily sidesteps this issue by implying that we can simply assume that 12,103km has the same meaning in each instance.
But this is not how meaning is in reality, each particular instance of usage has peculiarities unique to that context of usage. So in your example, the measurements might have been done in different ways for example, under different circumstances. These features, peculiarities which are unique to the particular circumstances, are known as accidentals. Therefore we remove, ignore, or make exceptions for the accidentals, and when two measurements are the same with respect to the apprehended essentials, we might say that the measurements are the same.
Of course two distinct measurements, even of the same object are never truly identical. Each act of measurement is unique, due to the difference in circumstances. Therefore we need to rely on an a priori principle to say that one measurement of 12,103km is the same as another measurement of 12,103km. Consequently, we compromise and say that the two measurements are "equal". And "equal" becomes a compromised sense of "the same", as it ignores the accidentals and applies only to what is determined as essential, depending on the purpose.
That's right. It's what some call an explication.
Quoting frank
Yes. That's right.
I agree that you have some reading comprehension issues.
If you have a substantive reply, I'm all ears.
But as it stands, your post looks again like passive-aggressive posturing.
It wasn't for your benefit. It was in case someone reading along was thrown by your bizarre interpretation. I was confirming that you're intentionally veering from Kripke's thinking and inserting your own untenable views.
Correct me. Set the record straight.
Put your balls on the anvil.
Say something substantive.
I don't debate MU, and I don't debate you, for pretty much the same reason.
I'll respond when you're inserting your own garbage in Kripke's mouth, for the reason I mentioned.
So Banno and MU on the same thread are double trouble?
Yep. :scream:
Kripke asks on page 177: "Is everything that is necessary knowable a priori or known a priori?". He writes page on 178: "So we certainly do not know, a priori or even posteriori, that every even number is the sum of two primes.
There is a difference between knowable a priori and known a priori.
Taking a simpler example of cardinal numbers, 1,2,3,4 etc. If numbers are invented, and only exist in the mind and not the world, it is certainly true that not every cardinal number is known a priori, because there are an infinite number of them. However, if numbers are invented, every cardinal number is certainly knowable a priori.
We may not know something that is necessary a priori, even though it is knowable a priori.
I know The Red Sox will win their next game, I know The Eiffel Tower is in Paris and I know that I am looking at the colour red. The word "know" is being metaphorically, in that it has degrees of certainty, because language is inherently metaphorical
Similarly, the word "same" is being used metaphorically having varying degrees of certainty.
I know a priori, before using language, that language is metaphorical. The a priori principle is that language is metaphorical. that "same" is being used metaphorically.
I'm not sure about the general case, but in the case of this paper I agree. I think I'm just marking where things are becoming strange for me. At this point I realized I wasn't sure what Kripke really meant by object.
One way in which this makes sense is that he's speaking to people who emphasize predication as how a person picks out an identity, at least explicitly in the talk. So in that way of looking at the logic I think I agree -- certainly every object is necessarily self-identical, insofar that necessity can be quantified over propositions at all.
However, the belief that non-existent objects have properties is at least unintuitive. Not that it's wrong, I'm just not sure what objects are now. Also, there's something funny about applying negative predicates to names, I think, even though logically there's no difference given negation is always a primitive.
... Yeah, just marking things that seem different -- not just to criticize (though maybe at some point), but to figure it out.
I would say, that your example shows the existence of ambiguity rather than metaphor. Although metaphor often makes use of ambiguity, the two are not the same. And in logic, we ought to make an attempt to reduce ambiguity, as this will increase the degree of certainty. We can reduce ambiguity and increase certainty by employing axioms which leave no room for ambiguity.
There are varying attitudes with which we can approach the production of logical axioms in relation to ordinary language use. At one extreme we try to adapt axioms to match the habits of ordinary language use. At the other extreme we attempt to curb the habits of language use, conforming them, and even producing new habits, to match contrived and artificially created axioms.
Language use is an habitual activity. Habits may be judged as good or bad. So the question of whether an existing habit of usage ought to be incorporated into a logical system requires a judgement as to whether it is a good or bad habit. And, the question of whether a new habit ought to be encourage or produced, as the result of introducing a new axiom, requires a judgement as to whether it would be a good or bad habit.
Ok. Thanks.
My next post will be about heat and the motion of molecules. One could easily become paranoid about being thrown off TPF for not sticking to the OP.
Regarding "possible worlds"
Kripke wrote: 1) What do I mean by rigid designator? I mean a term that designates the same object in all possible worlds. 2) All of this talk seems to me to have taken the metaphor of possible worlds much too seriously in some way 3) And if the phrase possible worlds is what makes anyone think some such question applies, he should just drop this phrase and use some other expression, say counterfactual situation, which might be less misleading.
IE, one can use the phrase "possible world", as long as one takes it metaphorically.
Existence
I proposed that if in this actual world, all the properties of Hesperus disappeared, then Hesperus would also disappear. You made the point that even if Hesperus didn't exist in one possible world, it may still exist in another possible world.
I agree that even though Hesperus no longer existed in this actual world, it could still exist in a possible world.
However, these are different kinds of existences. The first refers to something physically existing in the actual world and the second refers to a possible world existing in the mind.
Agreed. Which returns to I think a major bone of contention in Kripkes thesis, with respect to classes of statements of knowledge and of metaphysics, where he says, pg 177, Now I hold that neither class of statements is contained in the other.
This is to categorically deny the validity of a priori knowledge, the statements of which are always metaphysical, and by such denial the very possibility of purely logical truth disappears. And if that is the case, then purely logical conceptions, in particular, the modal relations under which this entire thesis is constructed, are empty.
Your leave no room for ambiguity is the very same thing as the validity of principles, and the increased certainty arises from the subsequent employment of them in deductive inferences, which are only and always from pure thought, a quite metaphysical enterprise, I must say.
Just in passing ..rhetorically speaking.
Heat and the motion of molecules independent of any observer
Kripke wrote: "First, imagine it inhabited by no creatures at all: then there is no one to feel any sensations of heat. But we would not say that under such circumstances it would necessarily be the case that heat did not exist; we would say that heat might have existed, for example, if there were fires that heated up the air."
Beginning with this lectern, this lectern is made of wood. If it had not been made of wood it would have been a different object, so this lectern is necessarily made of wood. This sounds reasonable.
This raises the question as to whether objects such as this lectern exist over and above their properties, in that if all the properties of the lectern were removed, would this lectern remain. Would Hesperus remain if all its properties were removed. Would heat remain if there were no molecules in motion. As no example of an object existing having no properties can be found in the world, it must be concluded that an object cannot exist in the world independently of its properties.
Kripke would say heat has essential properties. These essential properties exist in all possible worlds, and as such heat is a rigid designator. Objects have properties, and for Kripke, some properties are essential and some non-essential. This can only be a human judgement. Human judgement cannot exist independently of any observer. In a mind-independent world the motion of molecules cannot be judged to be essential or non-essential, meaning that heat cannot be a rigid designator, as the world has no means of judging which properties are essential and which non-essential.
IE, heat cannot be rigid designator in a mind-independent world.
Since an object with no properties is beyond imagination, it's not so much that Hesperus would disappear as that we're no longer talking about a possible (or the actual) world. We would just talking nonsense.
This is not what Kripke intended by specifying rigid designators. He was just adjusting some old assumptions about necessity to allow for our use of hypotheticals.
I more or less agree, but my long-term project is to show that language is fundamentally metaphorical. "Time is a thief" is a metaphor in that time is not the same as a thief. "Object A is object B" is a metaphor in that object A may be similar to object B, but object A can never be the same as object B. "Hesperus is Phosphorus" is a metaphor in that Hesperus may be similar to Phosphorus, but Hesperus can never be the same as Phosphorus.
I agree. Objects such as lecterns cannot exist in the world independently of their properties, as objects in the world are no more than the set of their properties.
You're pushing Hume's bundle theory. Fine. Kripke isn't saying that objects exist independently of their properties. That would just be ridiculous.
I'm starting to see what he's getting at, I think.
For me, I'm hesitant to call "the motion of molecules" rigid because it doesn't pick out the same individuals in all possible circumstances. I'm hesitant about the relationship between names, aggregates, and whether or not aggregates are objects. The mereological problem is what I keep thinking of.
But if it's just a way of talking, and not mereology, then the truth/falsity of a particular proposition isn't what's at issue. I'm getting stuck on the ontology when he's talking epistemology. What's at issue is the necessity of identity statements, which at this time seems to me just to be anything of the form "x is y", where x and y pick out the same object.
So "heat is the motion of molecules" fits the form, and thereby are objects in terms of the logic. Kripke isn't even taking a stand on the truth/falsity of that statement as much as he's using it because identity theorists of the mind-body use it as an analogy to say "there are contingent identity statements", which is the belief Kripke is arguing against -- that if these be identity statements at all, then they are necessary.
I'm seeing this in the lectern example, where he states at p 179/pdf-18:
Especially at the beginning it goes along with his other examples where he doesn't assert the truth as much as suppose the propositions are true in order to demonstrate necessary identity across possible worlds, since possible worlds are just counter-factual circumstances that are plausible (hence why, in the circumstances which Kripke was talking, the wooden lectern was necessarily not-ice, and since it was not-ice, it was necessarily not made of the Thames from the beginning of time)
It's the use of the counter-factual "world" (circumstances) that he's taking issue with -- in the counter-factual circumstances, the names pick out the same individual, and so -- given that every object is necessarily self-identical -- the object picked out in both the actual and the possible circumstance are necessarily the same individual, whatever the truth of the statements made.
I've suggested several times that possible worlds are a convenient way of dealing with counterfactuals. If you wish to call them a metaphor, go ahead.
The salient piece for proponents of descriptions is that a proper name does not refer by making use of some description.
Quoting RussellA
I agree the notion of removing all of an objects properties is problematic. I don't think that is mentioned anywhere in the article - is it?
I'd also draw your attention to the difference between picking out an individual using a name and picking it out using a demonstrative.
Can I again commend the Donellan paper mentioned earlier to you? The Thales example is telling.
Quoting frank
Yep.
I think we again are not in disagreement.
The wooden lectern is ipso facto necessarily wooden, yet that is understood only empirically. Unfortunately it's an example that is prone to misunderstanding, as in various posts in this thread.
Quoting Moliere
This is perhaps the key concept, and the article is an articulation of how we can use this approach to talk consistently about counterfactuals. At the time of writing, under the influence of Quine, counterfactuals were generally thought senseless. After this article, and Kripke's other work, they became an important part of the analytic toolkit.
I'll say again, perhaps more explicitly, that I do not think the examples of heat and pain work to Kripke's advantage. This because heat and pain are not treated well when treated as objects. But while rejecting these last few arguments I am in agreement with much of the remainder of the article.
In the first case "know" is used incorrectly; you cannot know that The Red Sox will win the next game. In the second case you are merely repeating a well-worn fact. In the third case the "know" is redundant; you are just looking at something red (if you are).
In the first case you have left something out; you don't know, you feel you know, you believe. In the second case it is not really as if you know, it is that "it is well known". If you've never been to Paris, then you cannot correctly say that you know the Eiffel Tower is there, but rather that you merely accept what is generally accepted as a fact; again you beleive. In the third case the "know" is redundant; you see something red, that's all.
Similarly with same; some uses are ambiguous, but I don't think it is a matter of metaphor. If you have a red 1968 Ford Mustang and so do I, I might say " Oh look, we have the same car", but something is left out, making the statement strictly incorrect; we don't have the same car, but we have the same kind of car.
The premise of the discussion is that "my pain" is a rigid designator. I think this mistaken, for reasons identified by Wittgenstein in his discussion of pain. That's perhaps much the same objection as found in the Malcolm article mentioned. In my view a pain, like a sensation of heat, is not an object or individual in the sense required for it to be designated by a rigid designator. "I have a pain in my foot" and "It feels hot" are not suitable demonstratives. But that's another argument.
But we are here to talk about Kripke's account. And I think that, if pain is taken as an object or individual, rigidly designated, then Kripke's argument is pretty much correct.
That is, given the way Kripke developed here to talk about rigid designation, if that pain is rigidly designated, and that brain state is rigidly designated, then if they are identical, they are indeed necessarily identical.
And that does present a problem for identity theorists.
Either way, one must conclude that mental states are not the very same thing as brain states.
We already knew that, insofar as we can be aware of mental states, but not of brain states.
This is the law of identity in a nutshell, as composed in Aristotle's Metaphysics. A thing is necessarily the thing that it is, because if it were not, it would be something else.
Quoting RussellA
The issue of whether or not a thing necessarily has properties is resolved by the implications of the law of identity. It is properties which make one thing distinct from another, so the law of identity implies that a "thing" necessarily has properties in order to be a unique particular.
Quoting RussellA
You only have this issue if you do not distinguish between the subject and the predicate, or object and property. In your quote, "time" is the subject, and "is a thief" is the predication. But predication is not the same as saying object A is object B. However, if through Platonism we represent properties as objects, then we might create that problem.
Quoting Moliere
Just out of curiosity, how could we account for radiant heat with this type of definition? Radiant heat is a real form of heat which we feel. Yet in that case, heat moves from object A to object B without the medium of molecules in between. So how would that heat get from A to B without moving through molecules in between?
I think we'd interpret radiant heat as molecules. (and, truthfully, that's how I understand Newton's notion of light -- they are little light particles)
In that case there would not be a necessary identity. And I think this gets to why I was so confused up front, too -- heat is not easy to define, especially in physical terms. We all basically get what it means in a generic sense, but that's it. So it doesn't seem like something I'd call a rigid designator, even in the normal sense of a proper name (unlike, say, Nixon).
It's the form of "NAME is NAME" -- heat and motion taken as names, where in the counter-factual we are able to refer to both heat and motion and say motion is not heat (because we are able to refer to the very same thing, whatever it is we were talking about) -- and refer to the same thing in both cases so that we can assert that these things are false. (else, to get transcendental, how else you know that "heat" refers to the same thing in the counter-factual than in the factual?)
We almost got to disagreement. Maybe next time. :)
Thanks for pursuing the thread. The explanations from different people finally got me to wrap my head around the baby idea.
Quoting Banno
Cool. Nice that it finally clicked, in its own terms.
Yeah, I was definitely getting stuck on the examples. The mere "details" ;)
Well, it's all reducible to energy. And since the conservation of energy is universal, it would be the same in all possible worlds which are equipped with Einsteinian principles. Since "energy" is more universal, why not set it as the rigid designator instead?
The problem though, is that if heat is defined as the motion of molecules, this doesn't account for all the forms of heat in the external reality, because a principal form of heat is radiant heat, and this is clearly not a movement of molecules. However, we do feel heat as the movement of molecules within our bodies, even radiant heat is felt that way. So by restricting "heat" by this definition, "motion of molecules", we restrict it to the sensation of heat, and so our understanding of "heat" under this definition is contingent on experience.
So we can't proceed from this definition of "heat" to show that heat is anything other than contingent on experience. And Kripke's stories about how it could be otherwise are not relevant, because he portrays heat as necessarily the movement of molecules, when "heat" is supposed to refer something external to the sensing body, and this is incorrect because much heat is radiant. So if we want to portray, or define "heat" in a way such that there can be a necessary relation between the word and the definition, we need an idea closer to "energy", which encompasses all forms of heat which are believed to exist. This would be the ideal conception of "heat", the one which includes all forms, and the external thing which that name refers to would be the Form of heat (Platonism).
Yes, much of language is like that, ambiguous, in that rarely in practice if someone says "object A is object B" do they say in what sense they are using "is".
If I am using "know" metaphorically, ironically, wryly, jokingly, humorously or sarcastically, it is not being used incorrectly.
Kripke wrote page 174: "All of this talk seems to me to have taken the metaphor of possible worlds much too seriously in some way."
===============================================================================
Quoting Banno
Within Bertrand Russell's Theory of Descriptions, a proper name refers to a set of true propositions that uniquely describe a referent.
Kripke and Donnellan rejected Descriptivism. Kripke described Descriptivism such that (1) To every name or designating expression 'X', there corresponds a cluster of properties, namely the family of those properties ? such that [speaker] A believes '?X'
For example, to the name Aristotle there corresponds the properties Greek, a philosopher and a teacher. It is these properties that refer to the referent.
A property, such as being Greek, is also a description. As a proper name corresponds to a cluster of properties, and as properties are also descriptions, then surely doesn't Descriptivism make use of descriptions ?
===============================================================================
Quoting Banno
Kripke wrote: "We can talk about this very object, and whether it could have had certain properties which it does not in fact have. For example, it could have been in another room from the room it in fact is in, even at this very time, but it could not have been made from the very beginning from water frozen into ice."
Kripke also wrote:"In fact, it would seem that both the terms, my pain and my being in such and such a brain state are, first of all, both rigid designators. That is, whenever anything is such and such a pain, it is essentially that very object, namely, such and such a pain, and wherever anything is such and such a brain state, it is essentially that very object, namely, such and such a brain state."
I agree that the possibility of removing all the properties from an object is not specifically mentioned in the article, but the problem of which properties may be removed from a rigid designator without affecting its status as a rigid designator must surely be important in understanding the article.
Objects have properties. Possible properties of this lectern are made of wood, made of ice, in another room, etc. A name is a rigid designator by virtue of having certain essential properties, whereby non-essential properties may be removed without affecting its status as a rigid designator. Kripke doesn't address the problem of how is it determined which properties are essential and which non-essential.
For example, some may believe that whether this lectern to be in this room or outside is clearly not an essential property, yet others may believe that the location of this lectern is an essential part of its identity, in that a stand made of wood outside a lecture theatre is not functioning as a lectern.
The article can only make sense to me if I can understand how is it decided which properties can be removed from a rigid designator before it no longer is a rigid designator.
===============================================================================
Quoting Banno
Even Donnellan admits of description within proper names.
He wrote: [i]"Nevertheless, so long as the user of a name can fall back on such a
description as 'the person referred to by Aristotle', the principle of identifying descriptions may be salvaged even if at expense of having to elevate one type of description to special status."[/i]
Pardon me, but it seems to me that this locution is misleading; as soon as the word 'if' appears, you are talking about a possible world, but then you doubly return us to 'this' and 'actual' world. But this actual world is necessarily the way it is, and not the way it would be if anything was different.
If you see what I mean. Or indeed, even if you don't.
In this world, Hesperus exists. If Hesperus didn't exist in this world, it could exist in a possible world.
If Hesperus didn't exist in this world, in which world would Hesperus not exist in, this world or a possible world ?
That's not true. We hypothesize about possible entities all the time. Sometimes we make them real.
If Hesperus didn't exist in this world, it wouldn't be this world, it would be that world.
Try it like this: instead of "if" always use "if in a possible world"
Then one can say "If in a possible world Hesperus didn't exist, x,y,z.
This is the same meaning as "If Hesperus didn't exist, x,y,z.
But when the substitution is made in your sentence, we get
"If in a possible world, Hesperus didn't exist in this world, ..."
That's already a contradiction, whatever comes after. my reply above makes no sense, and neither does your post that it replies to; but my reply at least has the merit of being a feeble joke.
Seems to me you want to make more of this than it will hold. Sure, it's a metaphor, a way to talk about counterfactuals. That's a turn of phrase in Kripke's hands, not the theory of meaning you want to turn it into.
Kripke's theory of meaning is causal. I't certainly not metaphorical.
Quoting RussellA
Sure. But proper names do not refer by using some description, in the way that Russell supposed. Kripke and Donellan demonstrate this.
Quoting RussellA
Exactly wrong.
Note that, as I've been at pains to point out, the case of this lectern is an example of a demonstrative, not a proper name.
Frankly, you have two theories, that names stand in for descriptions and that language is metaphorical, and you are interpreting the text in such a way as to maintain those theories. Kripke and Donellan, so far as I am aware, accept neither.
It's an example of the use of a demonstrative: This. It's not a proper name.
Now Kripke shows that proper names do not rely on descriptions. But that need not apply to demonstratives.
Note also that Kripke introduces it specifically in order to talk about this topic: "A question which has often been raised in philosophy is: What are its essential properties?"
While he uses a demonstrative to talk about essential properties, it does not follow that he thinks things designated by proper names have essential properties. Specifically, he does not think that a proper name refers in virtue of the essential properties of the thing named.
This by way of showing that the lectern example has little bearing on the use of proper names.
Now to the syllogism on p. 180, which caused some confusion amongst posters. Notice that (P??P) is an invalid inference. It is true that the cat is on the mat, but it is not necessarily truth that the cat is on the mat. Now the theorems of predicate calculus and such are necessarily true, true in all possible worlds, in virtu of their logical structure. But (P??P) is not amongst them. It is not a necessary truth in virtue of it's logical structure. If it is a necessary truth, it is for some other reason.
So what are we to make of
How can "This lectern is not made of ice" imply, a priori and in all possible worlds, that this lectern is not made of ice?
And the only way that I can see for this to be so is if the demonstrative, "this lectern", in some way already implies that the lectern is not made of ice. It's standing in for something like "this wooden lectern is not made of ice", which is true a priori.
Which is a convolute way of saying that if the lectern before us were made of ice, it would be a different lectern to the wooden lectern that is actually before us.
A corollary of all this is that the essence ascribed here is a long way from the Aristotelian notion of "to ti esti", "the what it is", that so confused his latin translators that they had to invent a new word.
It appears someone's been reading the SEP. <--- That sentence has a rigid designator in it. It actually comes down to what I meant by it. Don't forget that meaning is found in use, not in analyzing abstract collections of words.
As for the rest, you've gone out into controversial territory trying to find a way to deny what pretty much everybody else thinks: which is that Kripke was contradicting Quine regarding essentialism.
Bon voyage.
Sure, I found an interesting tidbit in SEP. Yes, SEP is a proper name. Proper names can be used to pick out an individual, without paying regard to their attributes.
And I've explicitly pointed out that Kripke is arguing against Quine; that's not something I wish to deny.
Whatever your point was, you haven't actually made it. And that is the pattern to your posts: somewhat snarky half-statements.
If you have a genuine criticism, a useful comment, or even another interesting tidbit, set it out.
You make this kind of statement a lot. Set out your argument, do you have anything substantive, if you have a point, make it. Then you promptly respond to the first three words someone wrote and ignore the rest.
I'm sure you can find someone to engage you. It's not going to be me. :razz:
In reply to you, yes, indeed.
Quoting frank
Then why do you insist on engaging? You are, after all, on this thread, replying to my posts, and you need not be.
That's classic passive aggressive shite: "I'M NOT GOING TO TALK TO YOU, IN THE LOUDEST WAY POSSIBLE".
(I accidentally bumped the caps lock there, but decided to let it stand.)
Sure, you can use it any way you like, but if you want to maintain a distinction between knowing and believing, then I don't think loose or ambiguous usages are a good idea.
I think the kinds of uses you refer to have no philosophical significance other than the already uncontroversial point that there are other kinds of linguistic usages apart from the strictly propositional.
To put that more correctly, Meta's posts, as usual, serve to show that the subject is confused.
Totally agree, exactly my point.
True. My new understanding is:
From the SEP Rigid Designators, Kripke addresses the objection that we cannot talk about someone without first having some qualitative criterion of identity, an essence, and if we know of no such essence we cannot meaningfully talk about someone.
Kripke addresses the objection that we cannot meaningfully talk about you, with respect to another possible world, without first having some qualitative criterion of identity, some qualitatively distinguishing mark that allows us to pick you out from other objects in the world at issue, in order to assign your name to the right person, i.e., to you, as the individual that satisfies the qualitative criterion. This criterion would appeal to your essence (or be an essence: see Plantinga 1985, pp. 857; 1974, p. 98; recall, for this example, the minimal requirements of weak necessity), in the minimal respect that the criterion must be something that you and you alone have with respect to any given possible world. As an objection, the worry is that we know of no such qualitative criterion so we can not meaningfully discuss you, with respect to any merely possible world.
From Wikipedia Causal Theory of Reference, Kripke outlined a causal theory of names whereby you don't need to be able to describe what is being named, but after naming an individual in an "initial baptism" the name continues to refer through a causal chain. In fact, although the meaning of the name may change with time and use, the new meaning becomes the new "reality".
[i]1) a name's referent is fixed by an original act of naming (also called a "dubbing" or, by Saul Kripke, an "initial baptism"), whereupon the name becomes a rigid designator of that object.
2) later uses of the name succeed in referring to the referent by being linked to that original act via a causal chain.
In lectures later published as Naming and Necessity, Kripke provided a rough outline of his causal theory of reference for names. Although he refused to explicitly endorse such a theory, he indicated that such an approach was far more promising than the then-popular descriptive theory of names introduced by Russell, according to which names are in fact disguised definite descriptions. Kripke argued that in order to use a name successfully to refer to something, you do not have to be acquainted with a uniquely identifying description of that thing. Rather, your use of the name need only be caused (in an appropriate way) by the naming of that thing.[/i]
Notice that this doesn't mean you can't have a description in mind when you talk about Paris, for instance. It just means it isn't necessary.
I think that's where my thoughts are coalescing at the moment -- to be able to even talk about a counter-factual, if all names were were descriptions, then by positing a different description of a named object we'd be picking out something different. Counter-factuals would actually just be us talking about different objects no matter what. That's why using "this" (though I'm picking up what you mean by "this" not being a name, now, ala Kripke -- since that's what he's speaking against, is Russel's theory of "this" counting as a name) with the lectern sunk home with me -- if descriptions are really all there are to names, then "this lectern is made of ice" is already picking out another lectern. That's why he's focusing on negative predicates, since the lectern he's talking about is necessarily itself, and it is a wooden lectern. And then the description is not picking out another lectern (another "name"), but the same one, even by the description.
"This lectern" is quite likely to be used as a rigid designator. Banno was throwing some spin in there. There might be cases where "this lectern" is non-rigid, but you'd have to pick that up from context.
Keep in mind that Kripke is focusing on ordinary language use. This is not an examination of a logical language, so meaning is truly use here.
In a case where "this lectern" is a rigid designator, the baptism is likely to have just happened. It's as if I named the lectern "Bob" but Bob equals this lectern.
The wooden lectern example is pointing to the way we think about objects. Note Kripke's emphasis on what we can and can't imagine. What he's saying should be very intuitive to you.
Heh, if so then I'm not understanding it because it is not very intuitive to me. :D
The bits on what we can and cannot imagine are somewhat opaque to me. Not that imagination isn't involved in thinking philosophically, but I'm naturally hesitant to say that imagination is the limit of philosophical thinking.
"This lectern" functions rigidly in the paper, I agree. It picks out the same object across possible-worlds/plausible-circumstances. I can see how that's not a name, but I don't think it matters either too much to this part of the argument if I'm reading it right at least.
Reading over it again now... I think the lectern example is where Kripke is showing how we can derive an a posteriori necessity.
So we have
P -> [] P
From a priori analysis of the lectern we can conclude that insofar that any particular lectern is made of wood, then it necessarily is not made of ice.
Then, from a posteriori investigation, we infer
P
That is, though we could be wrong, the lectern is made of wood.
Therefore, it is necessarily not made of ice
So we get a necessary conclusion from a proposition believed due to a posteriori methods.
So he's talking about, I gather, the distinction he wants to make between a posteriori/a priori, and contingent/necessary -- so that we can have necessary, a posteriori truths. (at least, as you note, within the way we normally use language rather than in some purified logical form)
Cool.
You might find something interesting in the SEP article Reference. It lists four intertwined theories of reference:
1. Descriptions
2. Causal
3. Character
4. Intentionalist
My view is pretty noncommittal. Why not just accept that we can make reference to something in virtue of a range of different ways of using words, and hence that these are ways we use words to refer, but no one of them, and even no particular combination, is the way we refer.
But then sometimes I agree with Quine that reference is inscrutable.
There's a long tradition of examining the ways we're bound to think. I think all philosophers make some use of that kind of exploration, but Hume and Kant are particularly notable for asking about the things we can and can't imagine. Kripke joins them in this for the purpose of showing that if we insist that all necessarily true statements are known a priori, this conflicts with the way we think about counterfactuals.
So there's no recipe here for speaking in a certain way. We're not identifying elements of grammar. We're analyzing a historic philosophical bias with the scalpel of...
the way we think. :grin:
Yep. We find necessarily true statements that are known a posteriori.
Perhaps; and example would be useful. I can't think of one, although perhaps something along the lines of Donellan's man with a martini would work.
But it also seems to me that "Bob the lectern", "That lectern", and "The wooden lectern at the front of the room with 'Bob' engraved on it" - a proper name, a demonstrative and a definite description - might each pick out the lectern in different ways, requiring differing theories of reference.
Counterfactual situations show that names do not refer in virtue of the properties or the descriptions of some object or individual.
And we must make a distinction between empirical, a posteriori stuff and grammatical, a priori stuff on the one hand, and necessary and contingent stuff, on the other.
hence,
Quoting frank
But I wonder what you make of the last arguments of the article, concerning the sensation of heat and states of mind. I've suggested that this is a misapplication of Kripke's argument, since that argument relies on fairly clear individuation - objects and individuals; but that after Wittgenstein it's not so clear that sensations and states of mind are the requisite sorts of individuals.
Further, the sensation of cold does not correspond to temperature, as shown in the video, and particular brain states do not correspond to particular states of mind, as shown by the irregularity of neural networks.
There's much plumbing to be sorted here, it seems.
Honestly I have to rethink it now. I'm not sure anymore.
Quoting frank
Okiedokie, if we're talking Hume/Kant then I'm on familiar ground.
So, compactly maybe: the historical philosophical use of imagination as a sort of ground for thinking about ordinary language's treatment of counter-factuals and contrasting that with the philosophic bias that all necessary and true statements are necessarily also known a priori.
So we can imagine this lectern is made of metal or in the next room, but we cannot imagine that this lectern was made from ice from the Thames. That's not plausible.
So, also, it seems that to make sense of this we have to accept Kripke's notion of "possible worlds" too. That, at least ordinarily, we can and do speak of possible worlds that pick out the same objects as the actual world, and so while this is a loose sense of "necessity" it's also one that people use.
Thoughts?
I wasn't able to find a copy of Davidson's paper that is not at least partially protected.
I don't want to say that it's specialized, because I really doubt that, I'm just noting that I think it's still worth looking at those examples with some suspicion, upon thinking it through.
In the case of counter-factuals, when we're talking about "heat is the motion of molecules" vs. "heat is a caloric substance that goes from one object to the other", then I think both must be picking out the same things in the case of the first part, but I'm not sure about the latter part still. Unless I allow strange things like "the belief that "the motion of molecules" means any physical object that cannot be perceived by our bodily senses because of how small it is which is in fact moving somehow" to be picking out objects between participants in a conversation. Maybe! But it's worth noting that we're getting into strange territory here.
So I agree with your conclusion here for sure:
Quoting Banno
I think that in his audience those examples were good to bring up because of the popularity, but that they are confusing to me, at least, for all the reasons we've already talked about and that you mention here.
We can do this simply with the law of identity. It implies that each object is unique, whereas essential properties are what things of the same type have in common. Therefore an object must consist of more than just essential properties, by the law of identity. In Aristotelian terms, an object has accidendal properties as well as essential properties.
The problem is that the law of identity is just an assumption based in intuition, it really cannot be proven. Some might say it's self-evident, some might say it's a priori, but these things really don't stand to be proven. That's why some philosophers (like Hegel) will dismiss the law of identity. So Kripke seems to want to prove something like the law of identity. But he uses faulty premises and his argument is unsound, so he does nothing toward helping us to understand the issues, he only obfuscates them behind a cloud of confusion.
It's most likely the case that what Kripke is trying to prove really cannot be proven, so the only way for his argument to be successful is if he can use enough smoke and mirrors to hide the faults in his premises.
However, there is much more at stake here than what meets the eye. There is the issue of the difference between an actual object (supposed to have independent existence in the world), and a possible object, (one signified with a name or description, but not necessarily assumed to have independent existence). Kripke's mode of argument effectively dissolves this difference, and this I believe is a serious ontological problem.
Using Kripkean principles, how are we to distinguish between a named or described object which may or may not exist in the physical world, and a named or described object which is supposed to have real existence in the physical world? This is why I stated that if we do not accept that the real object is the Platonic idea, we are forced into anti-realism because there is no other option for a real object.
Well maybe we can focus on this for a bit, at the risk of being off-topic.
The law of identity, like any law of logic, is a way of talking.
Asking for a proof of A=A is very much like asking for a proof that the bishop always moved diagonally. If it didn't move diagonally, it would not be the bishop. If A=A were wrong we would not be talking about A or =.
So it's not an intuition or an assumption.
Hence, it is not that "Kripke seems to want to prove something like the law of identity".
I think he takes it as given.
I think you misinterpret the law of identity. It says something about things, not something about the way we talk. It says that a thing is the same as itself. So if it says something about the way we talk, it is prescriptive, saying something about how we should talk. It is saying that we ought to talk about things as if they are the same as themselves. To use your bishop analogy, it's like whoever made up the game, making up the rules, saying we ought to have a piece which only moves diagonally, and this we will be called the bishop.
The law of identity is widely accepted, and that is because it is very intuitive. Logically though, we can deny it like Hegel does. We can argue for example, that in the act of becoming, which is the transition between not being and being what a thing is, the thing must exist as something because it's not not being, but it is also not the thing which it is when it is the thing which it is (by the law of identity). Hence the thing must be something, but something other than the thing which it is, in this mode of becoming.
So when we give priority to "becoming" as Hegel does in his dialectics, we can override the law of identity, asserting that the thing is something in this prior state, when it is becoming the thing that it will be, but is not yet that thing, and by Aristotelian principles it is only the potential to be that thing, which it will be by the law of identity. Then we say that the potential to be something is something. But since potential consists of many different possibilities, then the thing which that potential is, is like many different things at the same time. This violates the law of identity yet it is also very intuitive, if we allow that the possible thing is in some way a thing, because possibility is the potential for many different things. So we must violate that law when we say that the possibility for a thing is a thing.
Quoting Banno
I find it quite clear that he does not take it as a given. From what he writes, he obviously knows the law, and its meaning. But then he questions it, and so he has to find a way to state it which suits his purpose, 'If the table is not made of ice it is necessarily not made of ice' for example. This is just a reformulation of the law, a thing is necessarily the thing which it is. But he has qualified it with the empirical judgement of what the thing is, a wooden table, and restates it as a conditional. Notice he could state the conditional any way "if it's made of wood..." "if its made of rock..." etc.. So what he states has been derived from the law of identity but is a completely different form, being expressed as a specific conditional, rather than the general law.
Furthermore his "rigid designators" demonstrate that he actually has no respect for the law of identity at all. In each possible world, the thing denoted by the rigid designator is different from what it is in other possible worlds, having different properties. Yet he says that these different things are the same thing. Therefore "a thing is the same as itself" is very clearly violated.
The example of the thermometer may be a key into Kripke's necessary a posteriori.
We may know an effect without needing to know its cause
I observe the number on a thermometer change. I don't know what is causing the number to change, but I name whatever is causing the number to change as heat. The number isn't heat, but what is causing the number to change is heat.
Some hypothesise that what is causing the number to change is the motion of molecules, ie, heat is the motion of molecules. Others hypothesise that what is causing the number to change is caloric, ie, heat is caloric. If one of these hypothesise becomes with time self-evidently true, it becomes an axiom. Society then accepts as given the axiom that heat is the motion of molecules.
Both the motion of molecules and caloric are referring to the same thing, heat in the world, even if we never actually know what heat in the world is. In practice, we don't need to know what is causing the numbers to change, we don't need to know what heat in the world is, all we need to know is the effect of heat in the world, the numbers changing on the thermometer.
As long as we know the effect of heat, we don't need to know what heat is.
Kripke is using the word "heat" in two very different ways
We can have a particular sensation, which we name the sensation of heat. We name the cause of this particular sensation heat. The word heat is being used in two different ways, one as a name of an effect, the sensation of heat, and the other as the name of its cause, heat. The effect is very different from the cause, though they share the same name.
Kripke refers to the sensation of heat. Page 185: "There is a certain external phenomenon which we can sense by the sense of touch, and it produces a sensation which we call the sensation of heat."
Kripke also refers to heat as the motion of molecules. Page 170: Heat is the motion of molecules.
Heat as the sensation of heat in the mind
Kripke discusses possible connections between the sensation of heat and its cause: i) "So, it might be thought, to imagine a situation in which heat would not have been the motion of molecules" ii) "the motion of molecules but in which such motion does not give us the sensation of heat" iii) "Martians, who do indeed get the very sensation that we call the sensation of heat when they feel some ice which has slow molecular motion, and who do not get a sensation of heatin fact, maybe just the reverse".
Heat as the cause in the world of the sensation of heat in the mind
Kripke discusses possible causes of our sensation of heat: i) "First, imagine it inhabited by no creatures at all: then there is no one to feel any sensations of heat" ii) "the judgment that heat is the motion of molecules would have been false."
Rigid designators
The motion of molecules in the world is a rigid designator. As this lectern is made of wood , this lectern is necessarily made of wood, similarly, as these molecules are in motion they are necessarily in motion.
A sensation of heat in the mind is a rigid designator. As this particular sensation of heat in the mind is this particular sensation, it is necessarily this particular sensation, whatever it is named, in that it could have been named "heat", "cold", "apple" or "The Eiffel Tower".
Heat in the world as the cause of a sensation of heat in the mind is a rigid designator. As this lectern is made of wood , this lectern is necessarily made of wood, similarly heat in the world as the cause of a sensation of heat in the mind is necessarily the cause of the sensation of heat in the mind, whatever it is named.
Kripke concludes that heat is necessarily the motion of molecules
He wrote: page 187: "To state the view succinctly: we use both the terms heat and the motion of molecules as rigid designators for a certain external phenomenon. Since heat is in fact the motion of molecules, and the designators are rigid, by the argument I have given here, it is going to be necessary that heat is the motion of molecules."
There are two possible meanings to heat is necessarily the motion of molecules
The motion of molecules in the world has one possible meaning, although heat has two possible meanings.
Meaning one: Heat in the world is necessarily the motion of molecules in the world. There may be heat in the world, and there may be molecules in motion in the world. Both the heat in the world and molecules in motion in the world are rigid designators, but it doesn't of necessity follow that there is a link between them. For example, both "Nixon" and "Caesar" are rigid designators in all possible worlds, but there is no necessary link between them.
Meaning two: Heat in the mind is necessarily the motion of molecules in the world. The sensation of heat in the mind is necessarily caused by heat in the world, but as there is no necessary link between heat in the world and the motion of molecules in the world, there is no necessary link between the sensation of heat in the mind and the motion of molecules in the world.
Conclusion
Heat is not necessarily the motion of molecules.
In chemistry and physics, heat is the quantity of energy available for transfer between a system and its surroundings.
See the second video given previously. The sensation of heat is related to temperature, but more to the the rate of transfer of energy.
Quoting Khan
Heat is necessarily the motion of molecules.
The sensation of heat is not.
Again, Kripke's choice of example was poor. But this does not undermine the broader case that sometimes if A=A, then ?A=A.
But it must be kept in mind that this is a way to choose what counts as A
Here again is the issue of transworld identity. Kripke's answer is now the standard response.
I might have put my slippers on. I didn't. One way to express this is that in some possible world I put my slippers on. It is trivial that the person who, in that possible world, put on their slippers, was me. There is no issue of "the difference between an actual object and a possible object.
Quoting Metaphysician Undercover
Yep.
There is more.
Quoting SEP
Quoting SEP
To be sure, there are issues with transworld identity. They are not the issues Meta cites.
This will not answer the question for Meta. But keep in mind that Meta thinks [math] 0.\dot 9 \neq1[/math]
Fair enough. I don't think it's me.
In several posts you mistook other theorems for A=A. So take
Quoting Metaphysician Undercover
But P??P is invalid, and hence it cannot be an"reformulation" of P=P. And Kripke very carefully does not treat it as such. No consistent substitution into P=P will give P??P.
Quoting Metaphysician Undercover
This shows that your misunderstanding stems from the error I pointed out in my previous reply to you. The very same thing may have different properties in each possible world under consideration. It is the error Kripke describes here:
But the issue is not whether it is the "standard" response, the point is that it is not consistent with the law of identity, not whether or not it is the standard. As you may have noticed, I argue against standard mathematical axioms as violating the law of identity. That law was introduced by Aristotle to rid us of the sophistry produced by Platonic "objects". It effectively eliminates human ideas and formulae from having an identity as an object, by stipulating that identity is something unique to the particular, or individual.
There is no immediate problem in violating or denying the law of identity, as I explained in the last post. When we place "becoming", (the potential to be an object), as prior to actually being an object, and we give identity to that possibility of an object, instead of assigning identity to the actual material object, we circumvent the law of identity. But when this happens we are vulnerable to the type of sophistry which Aristotle formulated the law of identity to combat.
Quoting Banno
If you call violating the law of identity "trivial" then it is trivial. In your example, the fact is that you did not put your slippers on. If you conceive of a counterfactual in which you did put your slippers on, then the person in that possible world is not you, because you put your slippers on. It's just an imaginary Banno, the real Banno did not put slippers on. No stretch of the imagination will provide equivalence between these two. In one case we have a real existing person without slippers and in the other there is a fictional person with slippers. It's not you. That's plain, simple, and obvious. And, if we insist that the two are both the same person we violate the law of non-contradiction because we have the very same person with two contradicting properties (slippers on and slippers off) at the same time.
If instead, I didn't know whether you put your slippers on or not, and I want to consider both as real possibilities, then the issue is more difficult. I want to say that in one possible world Banno put his slippers on, and in another possible world Banno did not put his slippers on. I have no empirical observations of the real Banno, but I believe there is one, so I want to allow that this real person identified as "Banno", is represented in each of these logical possibilities. But really, these are only 'possible Bannos', one with slippers on, the other without. The real individual represented by "Banno" is somewhere else, and I only have fictional, possible Bannos. And this is where the matter gets tricky, because by the law of identity we must conclude that the real object identified as Banno is separate, distinct from these 'possible Bannos'. The 'possible Bannos' simply have no real identity. And trying to produce an identity for them will be an endless nightmare.
I think it is important to maintain this separation if we want to maintain a realist ontology. I want to say that independent of the two 'possible Bannos' there is a separate 'actual Banno', and the correct possible Banno is the one that corresponds with the actual Banno. So I say that the name "Banno" signifies a real object, the actual Banno, and in the possible worlds this name "Banno" holds a place for a possible representation of the actual Banno.
If we do not maintain this principle, that the name refers to an actual Banno, independent of the possibilities, then we allow for different sorts of non-realist ontology. Then there is no separate, actual object, only the supposed 'possible objects', and the correct possibility is decided by means other than correspondence with the real world, like in model-dependent realism.
Quoting Banno
Do you recognize that "A=A" is a symbolic representation of the law of identity, which is properly stated as an object is the same as itself?
Quoting Banno
I told you, the law of identity is not supposed to be valid, it is meant as a simple axiom, a self-evident truth. There is no validity to it, it is simply intuitive. So that "P??P is invalid" says nothing about whether it is a formulation of the law of identity or not.
So take the example, "if the table is not made of ice it is necessarily not made of ice". How do you validate "necessarily" here, without reference to the law of identity? You yourself say that this statement is not valid. However, the law of identity may be seen to support the use of "necessarily" here. The law of identity is a statement of necessity, an object is necessarily the same as itself. That's the way Aristotle described this law in his Metaphysics, for the very reasons explained above. When an object comes into being it is necessarily the object which it is, and not something else. That's a statement based in the nature of time, what has come to be is necessarily so. Banno is necessarily the individual who did not put his slippers on. The table is necessarily the table which it is. If it is made of wood, and not made of ice, then it is necessarily made of wood and not made of ice. The use of "necessarily" is supported by the law of identity. What has come to be is necessarily so. An object is necessarily the object which it is, i.e. the same as itself. The object which we call "the table" is necessarily the object which it is, i.e. the same as itself, therefore if it's not made of ice it is necessarily not made of ice.
Quoting Banno
That is very clearly a violation of the law of identity. In a possible world there is only possible things. So there are no things with an identity in a possible world. "The very same thing" can only refer to an actual thing. If we allow that the very same thing has different (contradicting) properties at the same time, in different possible worlds, then the law of non-contradiction is violated. The claim of "different possible worlds" does not provide an exception to the rule, because it is asserted that it is the very same thing, and clearly it cannot be the very same thing with contradicting properties at the same time. You might say it's a possible thing in a possible world, but then it has no identity and cannot be said to be the very same thing. Therefore we must adhere to the law of identity to avoid this contradiction, and maintain that there is only possibilities in possible worlds. And possible worlds are imaginary, so there are no things with an identity of their own in these statements of possibility. We ought to avoid that nightmare and quit looking for such an identity
Yeah, it is me. That's implicit in "I might have put my slippers on". It's a sentence about me, not about someone else.
And from there, your account goes astray. What follows in your post is erroneous.
But it's false, you did not put your slippers on. When you say "I might have put my slippers on" you are lying because you know that you did not. Therefore the statement doesn't serve to identify you, it can only mislead if we think that it does. That's where the problem lies. We ought not think that falsities serve to identify. The person identified in that statement as "I" is not a real person, because the statement is false, and the person stating it is not truthful because the real person did not put slippers on, and knows this.
Quoting Banno
This only follows if what you say is the truth. But it's not. You lie when you say ""I might have put my slippers on" when you know that you did not put your slippers on. Therefore the "I" does not refer to you personally, it refers to a deceptive image of you, a fiction. And no matter how you insist that it does refer to you, you are lying and it's all a deception.
So be it, if your will is to insist on deceiving.
The possible world in which I have slippers on is not the one in which I have slippers off. Whether you like it or not, this is not a contradiction. The modal logic is consistent, as Kripke and others have shown in their considerations of possible world semantics.
Quoting Metaphysician Undercover
That's what I am saying. Yep. But without the metaphysical baggage you attach. A=A is valid. It is a necessary truth. When you say stuff like Quoting Metaphysician Undercover one is left to puzzle over the logic you are using.
Quoting Metaphysician Undercover
Simply, a sentence will be necessarily true only if it is true in every possible world. Quoting Metaphysician Undercover
No, I'm not. It is not true that I did not put on my slippers in every possible world, because having my slippers on is not a necessary attribute of Banno.
Quoting Metaphysician Undercover
Again, no, since the actual world is a possible world. That's been explained to you before.
Quoting Metaphysician Undercover
Sure, it's false in this possible world. You are left in the absurd position that the sentence "Banno might not put his slippers on" is not about me.
Anyway, I hope it is clear to others that Meta's account is quite at odds with Kripke's, and since there is little chance of Meta coming to understand modal logic, I'll finish up here; unless someone else has questions or comments regarding Meta's account.
What is contradiction is saying that it is the "very same" person in the distinct possible worlds.
Quoting Banno
Yes, it's consistent because they violate the law of identity, as I described. The three fundamental laws of logic, identity, non-contradiction, and excluded middle are all tied together. If the law of identity is violated, then contradiction can be taken as being consistent. Consistency is judged relative to the axioms employed. Remove the law of identity and all sorts of strange things become consistent.
Quoting Banno
The law of identity is not valid. If you think it is, then show the logic which proves it.
Quoting Banno
OK, so you deny any form of realism. Each possible world is just as likely to be true as any other because there is no real, or actual world to look at for correspondence. And, when you stated that you did not put your slippers on, you were stating this as a possibility rather than as what you believed was actually the case. I apologize for calling you a liar, you are just an anti-realist and did not state your perspective properly.
By what principles do you propose that I choose one possible world over another, to believe as the truth? In one possible world you put slippers on, and in the other you did not. There is no actual world, so how do you propose that I decide which of the possibilities to believe as the truth? There is no law of identity, so this person "Banno" put slippers on , and the same person, "Banno" did not put slippers on, both at the same time, and there is no actual or real person with that name. Where do I find a hint of truth here?
Quoting Banno
There's no doubt about that. I thought I made that clear in my first post on this thread.
It's consistent yet violates the law of identity?
Well, if it violates the law of identity, then it is by that very fact not consistent. But we know it is consistent; hence, it cannot violate the law of identity. As noted earlier, My bolding.
Quoting Metaphysician Undercover
Here's a tree proof:
https://www.umsu.de/trees/#A=A
The remainder of that post is... increasingly odd. It shows again the error Kripk point to here:
and here, again:
Quoting Metaphysician Undercover
Of course there is an actual world. It's one of the possible worlds.
Then comes:"But, all we need to talk about here is this: Is everything that is necessary knowable a priori or known a priori?" and the comments on Goldberg's conjecture.
I didn't go in to this in any detail, so I might revisit it.
Goldbergs conjecture is that every even natural number greater than 2 is the sum of two prime numbers. We do not have a proof of Goldberg's conjecture. But we know by calculation that it is true apparently up to 4×10^(18).
Since it is a mathematical statement, if it is true, then it is true in any possible world - it is necessarily true.
Since we do not have a proof, we do not know if the conjecture is true.
Hence we do not know a priori that the conjecture is true.
Btu if we did have a proof, then we would know a priori that it was true... we would know it was true independently of our experiences...
Now we know from Gödel that there are always mathematical truths that are not proven.
Well, that looks right. If there are unproven mathematical truths, they are not known, and hence not known a priori.
Of course, for Gödel the truth of such statements was relatively trivial - they said they were true, being of the rough form "This statement is true but unproven". The Goldberg Conjecture works as an example of a potential Gödel statement that is not quite so obvious - it's what such a statement might look like, intuitively true, true in every actual calculation, and yet unproven to be true. It becomes unclear what it might be to claim it is true a priori.
The law of identity
I don't disagree that if A = A then A = ?A. As you say "Hence, it is not that "Kripke seems to want to prove something like the law of identity.........I think he takes it as given." Yes, if heat is heat, then heat is necessarily heat. If the motion of molecules is the motion of molecules, then the motion of molecules is necessarily the motion of molecules. If the Eiffel Tower is the Eiffel Tower, then the Eiffel Tower is necessarily The Eiffel Tower.
However, the law of identity doesn't show one way or another that heat is necessarily the motion of molecules, rather than heat is the Eiffel Tower, for example.
Heat, temperature and energy are concepts and don't ontologically exist in the world
Although heat may be transferred by conduction, convection and radiation, keeping with Kripke's description of heat as the motion of molecules. I accept (for the sake of argument) that moving molecules ontologically exist in the world. Consider a body having moving molecules:
Temperature is the measure of speed of these molecules, the higher the speed the higher the temperature. However, temperature as a concept, as a measure of speed, cannot exist independently of the moving molecules. It cannot have an ontological existence in the world over and above the moving molecules themselves. If there were no moving molecules, there would be no temperature.
Energy as a concept is a measure of the number of molecules and their speed. Similarly, as a measure it cannot exist independently of the moving molecules. It cannot have an ontological existence in the world over and above the moving molecules themselves. If there were no moving molecules there would be no energy.
Heat as a concept is a measure of the transfer of momentum from one molecule to another. If a fast moving molecule hits a slow moving molecule, the fast moving molecule slows down, and heat has said to have been transferred. Heat as a measure of the change in movement cannot exist independently of the change in movement. It cannot have an ontological existence in the world over and above the moving molecules themselves. If there were no moving molecules there would be no heat.
Heat is a concept
In Bertrand Russell's terms, the existence of heat is not the first-order of an individual but the second-order of a concept. If I tell someone that the next bus will be arriving in 10 minutes, their knowledge has increased, in that my knowledge has been transferred to them. This does not literally mean that knowledge ontologically exists in the world. Similarly, if someone says that heat has been transferred from one object to another, this does not literally mean that heat ontologically exists in the world. Knowledge and heat as concepts are figures of speech.
"Heat is necessarily the motion of molecules" cannot literally be true
As heat is a concept that exists only in the mind and not ontologically in the world, and as moving molecules do ontologically exist in the world, the statement "Heat is necessarily the motion of molecules." cannot literally be true as it is comparing two fundamentally different things, though still valid as a metaphor, however.
Banno, consistency is a relation between the axioms or premises employed. It does not rely on the law of identity. But consistency is commonly related to non-contradiction. If the law of identity is not one of the axioms employed, then the law of of identity is irrelevant to consistency when consistency is determined strictly by non-contradiction.
Quoting Banno
Ha ha, very funny. I hope you meant that as a joke.
Quoting Banno
You don't really believe this do you? What about the error you just pointed to, whereby possible worlds are reckoned to be an actual place? How would you reconcile these two, your claim that the actual world is one of the possible worlds, and your insistences that it is an error to think of a possible world as an actual place you might go to?
This is where Kripke shows his true colours, as a deceptive sophist. He says it's an error to think about a possible world as if it were an actual place that one could go to, yet it turns out that the only realistic way to interpret "possible worlds" is that one of them is the actual world where we live.
Kripke is anti-realist, but is trying to distance himself from anti-realism:[quote=https://en.wikipedia.org/wiki/Modal_realism]Saul Kripke described modal realism as "totally misguided", "wrong", and "objectionable".[27] Kripke argued that possible worlds were not like distant countries out there to be discovered; rather, we stipulate what is true according to them.[/quote]
Notice, "we stipulate what is true according to them [the possibilities]." As I said, you are being lead firmly into anti-realism. You do not separate the representation (a logical possibility) from the actual world, as consisting of material objects with an inherent identity (by the law of identity). There is no such separation when you insist that the actual world is one of the possible worlds: https://iep.utm.edu/mod-meta/
This is the problem with Kripke's work which I pointed to already. If we accept his premises as coherent, we have only two ontological possibilities, Platonic realism, or anti-realism. If the "rigid designator" signifies a real object we have Platonic realism, because the logical possibilities are all ideas, mental fabrications, and we say that the mental fabrication is "real". But if we reject the reality of the mental fabrication, (logical possibility or possible world), then we have nothing independent of the mental fabrication, to call "the real world". The real world is just a mental fabrication, as you state here, "it's one of the possible worlds". This is firmly anti-realist, though sophistic authors will present it as a form of realism, "modal-realism", "model-dependent realism", etc..
The sophistry lies in the way that the supposed actual world is distinguished from the other possible worlds, in this anti-realist structure. To be consistent, all logical possibilities must be represented in the same way, as possibilities. The rigid designator signifies the same possible subject in each. So when you state a counterfactual such as "I might have put my slippers on. I didn't", you speak deceptively because you imply that one of the logical possibilities has a status which the other does not (what actually occurred). But you have no premise to make that conclusion. Therefore your statement is prejudiced and thereby compromised.
The issue is a logical dilemma. If one of the possible worlds is supposed to be the actual world, then we need some principles whereby we make that judgement, and decide what to believe as the truth. But if we introduce principles (premises) into this logical system whereby one logical possibility would be distinguished from the others as what is actually the case, that would give this one a status which the others do not have, rendering it as other than an equal possibility.
That's why we ought to reject Kripke's principles altogether. If every logical possibility is equally possible, as indicated by the definition of "rigid designator", and one of the possibilities is supposed to be the actual world, rather than a representation of the actual world, we have no real principles for judging the truth.
..and in the talking about, is the very containment of epistemological within metaphysical statements he denies.
Quoting Banno
.which is a metaphysical statement regarding knowledge. From a few instances of a posteriori proofs is developed a principle. For any instance other than from experience, in which the principle is the ground, the proof must hold as it did a posteriori. Otherwise, it is impossible to deduce how the principle could be thought in the first place.
Quoting Banno
It is already given no proof from experience is possible, in that the iterations of the statement are infinite. We have nothing with which to judge infinite conditions, except the logical validity of the principles by which the iterations stand as proven a posteriori, which is of course, the epitome of knowledge a priori.
Quoting Banno
We dont care if the conjecture is true, we cant ever arrive at its finality anyway; we only care that the principles which ground the conjecture, work together and do not contradict themselves. We know a priori the principles of universality and absolute necessity, from which is given the LNC. From the LNC is given validity of the conjecture, even without the possibility of empirical proof for it.
What it might be to claim it is true a priori, then, is just to show that if it isnt, the entire base of human intelligence, re: logic, is junk, insofar as if we cannot use the LNC to validate the conjecture, the use of it to validate anything at all becomes questionable, which is itself a contradiction.
Quite right. That's @Metaphysician Undercover's error. But given that a posteriori we know that heat = the movement of molecules, then it's the same in every possible world. Or at least, that seems to be Kripke's argument.
Quoting RussellA
I don't follow that. I don't see how molecules could exist but not their movement.
Quoting RussellA
Sure.
Quoting RussellA
Not so sure. Seems to me it means that the average movement of the molecules of one object has increased. That's a statement about how stuff is.
Quoting RussellA
I don't agree.
What will probably be argued by @Mww is that, if heat is the movement of molecules, then while we learned this, it is an a priori fact deriving from the definition of heat.
No so much. It's just that the sentences under consideration do not imply a contradiction. Your definition would only work for axiomatic systems. This definition works for natural deduction as well.
Quoting Metaphysician Undercover
Same problem. Possible worlds are stipulated, not recognised. The actual world is a possible world. The alternative would be to claim that the actual wold is impossible.
The remainder of your post verges on the paranoiac. I'll leave you to it.
So... we know stuff only by induction or by deduction?
Quoting Mww
You're saying there are truths that have no proof from experience and none a priori. Yep.
Quoting Mww
You're saying it doesn't matter if maths is true, only that it is consistent. Perhaps.
Quoting Mww
I don't see how this works, nor how it follows from what went before. We know from Gödel that there are mathematical truths without proofs. What's puzzling Kripke is what it might mean to call such truths a priori.
Heat is the motion of molecules ..as far as our experience informs us. Any empirical knowledge is contingent, therefore heat is necessarily the motion of molecules cannot be literally true. It is only as true as we know as of this point in our experience. Will it always be the motion of molecules? Probably, but we are still not logically justified in saying it is necessarily so. Humes problem of induction, T.H.N., 1.,3.,6., 1739. You know more of that old stuff.
Quoting Banno
Not quite. After we learn this, it resides in experience, such that we can say we know a priori heat is the motion of molecules without immediate testing or experience to prove it. Besides, if I read you right, if it is an a priori fact given from definitions, we wouldnt need experience to prove it.
-
Quoting Banno
We know empirical stuff by experience, we know possible empirical stuff, or empirical stuff possibly, by induction; we know a priori stuff only by deduction because there is no need for immediate experience on the one hand, and indeed there may not even be any on the other, for that kind.
Quoting Banno
Dunno why it should be puzzling. For that which is true a priori just means theres no immediate proof from experience, or no proof from experience possible at all. Whatever makes something true in such case, is merely logical.
Maybe he shouldnt confuse truth with that which is true. There are no empirical truths; there are only relations between things that do not contradict each other, which makes the relation true under the conditions from which the relation is given.
Im not a fan of true/truths as such. Far too ambiguous and subject to the inclinations of whomsoever is professing it. Plus, we gotta keep in mind just what kind of intellect is doing all this knowing and truthing and whatnot.
Well, see, if you assume this, or take it as a given, then it'll be hard to see why Kripke denies it. His approach is that it is worth reconsidering the relation between necessary/contingent and a prior/a posteriori.
We do at least agree that this is Kripke's approach, I hope?
Reference? Page number?
That Hesperus is Phosphorus, Tully is Cicero, The lectern is not made of ice... things known empirically that he claims are necessary truths.
No?
No, the alternative is to understand that the actual world is categorically different from the possible worlds. The former being the material world we live in, the latter being mental constructs. From this alternative perspective, to say that the actual world is a possible world is just a category mistake.
Quoting Banno
This is mistaken too. Things known empirically cannot be taken as "necessary truths", because empirical knowledge is fallible.
As I explained to you, this is why we need the law of identity, to impose necessity on the material world. This law makes a statement about the temporal nature of reality, asserting that what is is necessarily as it is. It makes no claim about specific things known empirically, and its necessity is purely intuitive.
I think this is a misunderstanding ..literally. Things that are known empirically is one thing; that there are necessary truths is quite another.
It cannot be an absolute necessary truth that H is P, if there was a time when they were known with apodeitic certainty to be different things. The Greeks were quite aware it is absurd to name one thing differently, which makes explicit it was necessarily true for them there were two things, and H was not P. It is only now necessarily true that H/P/V are all one and the same object, which makes the truth of the relation between H and P such that H is P, contingent on the time of its being understood.
Funny thing about that ..to be consistent with the Greeks, one must have a congruent experience of this particular celestial object, which is merely a bright spot in the sky in the morning and a bright spot in the sky at night, and nothing else whatsoever. Now we arrive at the real necessary truth, and that resides in the quality of whatever experience it is from which the knowledge is given. It never was necessarily true H was P, but it is certainly necessarily true whoever thinks they are, must have the exact same understanding of their experiences. Necessary truth isnt inferred from what is known, but deduced from the understanding of what may or may not eventually be known.
If you understand it is necessarily true an object made of wood cannot be made of ice, you must have already understood how an object made of wood manifests as an object of your experience. If you didnt already understand how a thing is, you couldnt say how it isnt. To say a thing known as being made of wood cant be made of ice, is merely an exercise in cognitive redundancy, which doesnt tell of anything not already understood. Whether one realizes it or not, is irrelevant; it still happens just like that, with no more or less theoretical speculative authority than Kripke himself posits in his thesis.
Actually I take that back. Kripke demeans his speculative authority but asking it repeatedly to be imagined, then informing that to imagine is itself flawed. Why imagine something, only to find out you had no warrant to imagine it? Or that you were doing it all wrong? It surprises me to no end Kripke thinks it even possible to imagine incorrectly, when the very conception of imagination as a human cognitive faculty or capability, precludes it as such, from ever being a source of truth.
That being said, I dont want to be told what I shouldnt do to arrive at something; I want to be told how to get there.
Quoting Banno
Yes, he does. But he neglects to mention how, and certainly doesnt inform as to the possibility that, the examples get to be facts.
. For explanations and examples, and other helps to intelligibility, aid us in the comprehension of parts, but they distract the attention, dissipate the mental power of the reader, and stand in the way of his forming a clear conception of the whole
Disclaimer: I understand this article is a transcript from an oral lecture. I also understand the audience more than likely has some philosophical background, which means they should have a clue about the subtleties not addressed in the lecture itself.
As well, being of analytic persuasion, Kripke has no inclination to metanarratives regarding human intelligence. So saying, a proper critique of the article as it stands on its own, confined as it is to language use and intentionality towards it, finds little support for the procedure by which the content of the article comes to be, and non-analytic philosophers will find little agreement with it for that very reason. The best to be said herein, then, is that Kripke is right in his own way but his own way isnt right.
Justfication three that "heat is the motion of molecules" cannot literally be true.
Relevant, as Kripke uses "heat is the motion of molecules" as evidence for necessity a posteriori.
I agree that space and time exist in the world, molecules exist in the world and the movement of molecules exists in the world.
I still don't agree that heat exists in the world in the same way that molecules and their movements exist in the world. As language transfers knowledge, heat transfers energy.
Heat
Heat can be transferred by conduction, convection or radiation. Conduction is a process in which heat is transported between parts of a continuum, through direct physical contact. Convection is the principle, wherein heat is transmitted by currents in a fluid, i.e. liquid or gas. Radiation is the heat transfer mechanism, in which the transition takes place through electromagnetic waves.
What these have in common is that heat is the process whereby energy is transferred from one body to another. Energy is due to the motion of molecules. Heat is the transfer of energy. Heat is not energy, heat is the transfer of energy. As energy is the motion of molecules, and as heat is not energy, heat is not the motion of molecules.
Heat is not a substance, it is a process
Mark Barton, PhD physicist with University of Glasgow, wrote: ""Heat" is a noun and is spoken of as a substance, even in technical language, but it's a misnomer. Strictly heat doesn't exist, it happens: it's the process of energy moving from one system to another via random microscopic interactions."
1) Heat is the transfer of energy.
2) Energy is due to the motion of molecules.
3) Heat is not energy
4) Therefore, heat is not the motion of molecules.
Well, Kripke isn't going to disagree with that. He says as much. so I don't see how it is a misunderstanding.
Quoting Mww
And absolute necessary truth? What's that? I know a necessary truth is true in every possible world. What does absolute do here?
The Hesperus-Phosphorus example has become overwrought. It's really pretty simple. If, in some possible world, Hesperus is not the very same as Phosphorus, then presumably we have a second, different planet. We would have the planet referred to as Hesperus, and another planet referred to as Phosphorus. This new planet would indeed not be Hesperus, even if it has that name in that possible world. Hence, even though there are possible worlds in which the words "Hesperus" and "Phosphorus" refer to different planets, Hesperus=Phosphorus in every possible world in which they exist.
Hence, that Hesperus is Phosphorus is an a posteriori fact, discovered by observation and necessarily true.
The rest of your post seems to be a move from looking at the logic to demeaning the logician.
Well, no. Heat is measured in Joules. It is the flow of energy from place to place.
I don't think we can finesse that away.
I wrote "heat is not energy". The consequence is that Kripke's statement Heat is the motion of molecules. is not true.
1) Heat is the transfer of thermal energy between two bodies, not the flow of thermal energy between two bodies.
Water when flowing along the Danube can exist independently of either Vienna or Budapest, however, heat cannot exist independently of the two bodies between which it is being transferred.
2) Are you saying that because heat is measured in joules and energy is measured in joules, then heat is necessarily energy ?
If so, then it would follow that because the height of the Eiffel Tower is measured in metres, and the height of the Empire States Building is measured in metres, then the Eiffel Tower is necessarily the Empire States Building.
3) Your argument is that heat, which is the transfer of energy, is energy.
From https://psiberg.com/thermal-energy-vs-heat
i) Thermal energy = It is due to the movement of particles in a system
ii) Heat = It is the transfer of thermal energy
Then it would follow that:
The banking system, which is about the transfer of money, is money.
Language, which is about the transfer of knowledge, is knowledge.
The football transfer system, which is about the transfer of football players, is the football players.
All these are true, but only metaphorically.
Gorgeous!
Even this is problematic because current principles of physics allow that the second body, the receiving body, is not necessary. Radiation of heat from an object is a function of the temperature of the object itself, in relation to absolute zero, such that thermal radiation is not currently understood in terms of a temperature difference between two objects. I believe this principle provides for Kirchhoff's law and "blackbody" physics. Consequently heat can radiate off into nothingness, and from this comes the proposed heat death of the universe.
Quoting Metaphysician Undercover
True, no second body is necessary for thermal radiation, in that the Sun has no "awareness" that the thermal radiation it emits will hit the Earth 8min 20sec later. The thermal radiation could continue into space without ever hitting a second body.
Quoting Metaphysician Undercover
Heat doesn't radiate. Heat is the transfer of thermal energy between two bodies.
There are three modes of heat transfer, conduction, convection and radiation. The transfer of heat by radiation needs no material carrier. Thermal radiation is electromagnetic radiation.
It is incorrect to speak of the heat in a body, because heat is restricted to energy being transferred.
Kirchhoff's law of thermal radiation is regarding a body at temperature T radiating electromagnetic energy. The body is not radiating heat, it is radiating electromagnetic energy.
The sun doesn't radiate heat, it radiates thermal radiation. If this thermal radiation doesn't hit a second body, as heat is the transfer of thermal energy between two bodies, no heat will be transferred.
When Theodore Parker said "Cities have always been the fireplaces of civilization, whence light and heat radiated out into the dark", he was using it as a poetic metaphor.
Ill own that. I looked at the logic, found it wanting, so tacitly disparage the logician positing the very thing I found wanting. And while I acknowledge my wanting means nothing in The Grand Scheme of Things, it arrives honestly, with due diligence, hence theres as yet no reason to rethink it.
If I understand you correctly, you say that heat is not in a body, it is the transferal of energy between bodies. However, thermal radiation, which is one mode of heat transferal cannot properly be called "heat", or even "heat energy", because if the thermal radiation does not reach another body there is no heat transferred, i.e. no body being heated. So heat transfers from one body to another, but it's never actually in a body. Nor is it in the radiation which transfer it from one body to another.
I assume then that "heat" refers to the activity which is the warming or cooling of a body. It is not necessarily a transferal of thermal energy between bodies, because a body can lose heat without another body gaining it. However, the body which loses heat never had heat within it in the first place, you say. "Heat" is really meaningless then, because if it referred to the activity of heating or cooling, it would necessarily be in the body, in order that the body could heat up or cool down. Or is "heat" just metaphor to you?
In ordinary parlance heating is "the flow of energy from place to place". Something that has been heated becomes hotter (than it was prior to being heated), and is said to possess a (greater) degree of heat. Of course it will cool if it is hotter than the surrounding environment. Cooling is also the the flow of energy from place to place.
Quoting Banno
Ah, the old 'appeal to authority' card has been played.
Guess that makes us a couple stubborn ol peas on either end of an overextended virtual pod, donnit?
And Im not eccentric. I got the proper stamped, signed, coffee-stained release papers to prove it.
Interesting exchange between you and Banno.
Pardon the quibble/pedantry. The above looks suspiciously like an equivocation fallacy. A substitution exercise shows it nicely.
If heat is the transfer of thermal energy, and we're using the term "heat" consistently, then in each and every instance where we use "heat", we ought be able to substitute that term with "the transfer of thermal energy", and retain all sensibility. However, we cannot successfully perform this exercise with the last statement in the above quote, for doing so results in the following...
There are three modes of the transfer of thermal energy transfer...
So, something is off. Could be just the use of "heat transfer". Is it just as sensible to say that there are three modes of heat, conduction, convection, and radiation. Or perhaps, that there are three modes of thermal energy transfer, conduction, convection, and radiation?
Could I be thrown off a philosophy forum for talking about the scientific nature of heat
In order to avoid being thrown off the thread for talking about the nature of heat, my reason is as follows:
Kripke concludes: "To state finally what I think, as opposed to what seems to be the case, or what others think, I think that in both cases, the case of names and the case of the theoretical identifications, the identity statements are necessary and not contingent."
One of the main planks of Kripke's justification is that Heat is the motion of molecules will be necessary, not contingent, and one only has the illusion of contingency"
Thermal energy is due to the motion of molecules. Therefore, one of Kripke's main justifications for a posteriori necessity is his belief that heat is thermal energy.
If heat is, in fact, not thermal energy, one of Kripke's main planks disappears. This casts doubt on the other planks in his argument, which in turn casts doubt on his conclusion regarding a posteriori necessity.
The word "transfer" is being used as a metaphor
The statement "The amount of heat gained or lost by a sample (q) can be calculated using the equation q = mc?T, where m is the mass of the sample, c is the specific heat, and ?T is the temperature change" is being used metaphorically rather than literally. Heat is a measure of the change in energy of a body. As a thermodynamic system does not contain heat, a body cannot gain or lose heat.
Britannica writes: "heat, energy that is transferred from one body to another as the result of a difference in temperature" Again, the word "transfer" is a metaphor. Heat has not literally been transferred from one body to the other.
Language is fundamentally metaphoric
Language, both in daily and scientific use is fundamentally metaphoric. Language as we know it couldn't exist without metaphor.
When you say "The above looks suspiciously like an equivocation fallacy", "A substitution exercise shows it nicely", "If heat is the transfer of thermal energy", "perform this exercise", and "something is off" you are using language metaphorically.
George Lakoff and Mark Johnson in Metaphors We Live By argue that metaphors are not merely stylistic, but are pervasive in everyday life, not just in language, but also in thought and action.
Andrew May in his article Metaphors in Science writes: "What is a scientific theory if not a grand metaphor for the real world it aims to describe? Theories are generally formulated in mathematical terms, and it is difficult to see how it could be argued that, for example, F = ma "is" the motion of an object in any literal sense. Scientific metaphors possess uniquely powerful descriptive and predictive potential, but they are metaphors nonetheless."
The word "transfer" is being used as a metaphor. Language would not exist as we know it without the use of metaphor. The use of metaphors is unavoidable in language, and we have to depend on context to tell us whether a word is being used metaphorically or not.
Don't you think it's the word "heat" which is the most metaphorical here? Afterall, you say heat is not in a body, nor is it actually transferred between bodies. It's simply an outdated term which no longer has any use in modern science because it does not jive with the way we understand the world by scientific principles. Yet it maintains descriptive power by way of metaphor, so it is still used. It's sort of like "the sun rises and sets". We know that "sunrise" is just a metaphor, and there is really a more complex scientific explanation as to what is really going on, but "sunrise" maintains its descriptive power through metaphor, regardless of the facts.
We can say that there are numerous possible ways to describe the very same thing. But as soon as we say that one of these ways is the correct way, or true way, we deny the status of "possible way" to the others, because they are now designated as incorrect ways. Then if used, they are metaphor. But if we adhere strictly to relativity theory, there can be no correct or true way, no literal truth, and all of the possible descriptions are metaphor.
If heat is not energy, this throws a spanner in the works in Kripke's argument for a posteriori necessity.
"Heat" has meaning as a measurement.
Heat is a measurement of the change in energy of a body. Heat is not a substance. A thermodynamic system does not contain heat.
Consider two bodies, one 1,000 kJ hotter than the other. Consider two bodies, one 80 metres taller than the other.
In what sense do measurements exist. In what sense does "1,000 kJ hotter" exist. In what sense does "80 metres taller" exist.
If The Empire States Building is 80m taller than The Eiffel Tower, where does "being 80m taller" exist. Does it exist in the world independently of any object, or does it exist in the mind of an observer.
If body A is 1,000 kJ hotter than body B, where does "being 1,000kJ hotter" exist. Does it exist in the world independently of any object, or does it exist in the mind of an observer.
It can only exist in the mind of the observer as a second-order concept, as Frege and Russell argued.
If heat is the measurement "being 1,000 kJ hotter", where does "being 1,000 kJ hotter" exist. Where does heat exist?
That's the problem with monism. It has no proper ontological principles to separate what's within the mind from what's independent of the mind. So we have Banno insisting "the actual world is a possible world". And the ensuing sophistry of "the alternative would be to claim that the actual world is impossible".
Yes, it is a concept that exists in the mind and not the world, such as pleasure, pain, government, democracy. But as a concept, it does have great descriptive power, even if what it is describing doesn't literally exist in the world.
It was a compliment.
No it isn't. The heat moves from one body to the other, in a process that can be described with mathematical predictability. Nothing metaphorical about it.
While we are there, any account of language as metaphorical is problematic. Metaphor is defined negatively, using a word or phrase to describe something to which it is not literally applicable. Hence in order to make use of a word metaphorically, it must already have a literal use. "Life is a highway" works because life isn't a highway, and it only works because we know what a highway is.
Hence any attempt to explain meaning in terms of metaphor begs the question.
Metaphors work by re-framing. They are verbal duck-rabbits.
Using mathematics to make a prediction does not imply that the process has been described. That's why Thales could predict the solar eclipse without knowing the proper orbits. And it's also why quantum physicists can make accurate predictions without knowing what's going on.
That made me laugh.
You've a very odd view on things, Meta. A mathematical model that makes accurate predictions is not for you a description. Fine.
Very obviously not, for the reasons I gave. Simply put, to count something is not to describe it. And no description is required for a count because the basic count is nothing but order. That's why there is a difference between quantity and quality.
Yeah, it is. This sentence contains five words. Counting can be describing.
Sure, counting can be describing, and mathematics can be used to describe things. But counting, and mathematical predictions are not necessarily descriptions. That's where the problem lies, and why I said "using mathematics to make a prediction does not imply that the process has been described".
This is the fallibility of essentialism. Essential features facilitate deductive conclusions, so we assume essences as necessary features, to facilitate logic. When the essences are eternal Platonic ideas, mistake is impossible. But if the named essential features are just the product of human judgement then they may not be true essential features, (like description, a posteriori, is not a true essential feature of mathematics, a priori), so the premise is unsound and the logic misleads.
So, back to the example. Heat diminishes in one body, and increases in another. Mathematical models can accurately predict this. But the process which you referred to as heat moving from one body to another, has not necessarily been described. The success of the mathematics doesn't provide you with the premise to even say that heat has moved from one to the other, as this in itself is a description which is unsupported. The mathematics shows coincident loss and gain of heat which is predictable.
Just this first paragraph is hopelessly confused. It seems to say that describing things is not to describe them...
Might try leaving it there, again.
I wouldn't read it that way. Rather, Kripke has already made his case and is applying his account to heat. I think we can drop the heat argument without much impact on Kripke's approach to modality.
He is not trying to justify his account of possible world semantics by appeal to heat.
His point is that once it is confirmed that lightening is a discharge of electricity, in any possible world with such a phenomena, if it does not have an associated discharge of electricity, it is not lightning but some other phenomena. That is, lightning is necessarily a discharge of electricity.
This example is an improvement, I think, because it does not rely in sensations.
Of course it seems like that to you, because you think that describing is an essential aspect of using mathematics. One cannot use mathematics without using it descriptively. So when I say that using mathematics is not necessarily descriptive, it appears to you like "describing things is not to describe them".
As I explained, that's where your essentialist attitude (the use of mathematics is descriptive in any possible world) misleads you. The essential property must be proven as such, and induction is fundamentally fallible.
Yes, Kripke first makes his case that if an identity statement is true, then the identity statement is necessary, and only later introduces the examples of names, heat and my pain.
But isn't his argument circular, in that if the identity statement "the Moon is made of blue cheese " is true, then he is arguing that the moon is necessarily made of blue cheese. Similarly, if the identity statement "the Moon is not made of blue cheese" is true, then the Moon is necessarily not made of blue cheese.
Kripke wrote " Identity statements..........That is to say, they are necessary if true; of course, false identity statements are not necessary." (abstract)
The problem remains in how do we determine whether an identity statement is true or not. How do we determine that two rigid designators refer to the same thing.
Kripke's case is that true identity statements are necessary
Kripke wrote: "To state finally what I think, as opposed to what seems to be the case, or what others think, I think that in both cases, the case of names and the case of the theoretical identifications, the identity statements are necessary and not contingent". (page 171)
Kripke makes a general argument
"If names are rigid designators, then there can be no question about identities being necessary, because a and b will be rigid designators of a certain man or thing x. Then even in every possible world, a and will both refer to this same object x, and to no other, and so there will be no situation in which a might not have been b. That would have, to be a situation in which the object which we are also now calling x would not have been identical with itself". (page 181)
Kripke gives an example using "this lectern"
"Here is a lectern......What are its essential properties............being made of wood, and not of ice, might be an essential property of this lectern...............could this very lectern have been made from the very beginning of its existence from ice.............If one had done so, one would have made, of course, a different object. It would not have been this very lectern........The conclusion ?P is that it is necessary that the table not be made of ice, and this conclusion is known a posteriori, since one of the premises on which it is based is a posteriori" (page 180)
Later on, Kripke refers to names, heat and my pain.
1) "If names are rigid designators, then there can be no question about identities being necessary" (page 180)
2) "We use both the terms heat and the motion of molecules as rigid designators for a certain external phenomenon". (page 187)
3) "In fact, it would seem that both the terms, my pain and my being in such and such a brain state are, first of all, both rigid designators". (page 188)
It may well be that true identity statements are necessary. The problem remains in knowing whether the identity statement is true or not. How do we know in the first place that "Cicero is Tully", "heat is the motion of molecules" and "my pain is my being in such and such a brain state" ?
Kripke said Heat is the motion of molecules, which is incorrect.
Heat is the energy transferred between objects due to a temperature difference between them. As you said, the amount of heat gained or lost by a sample (q) can be calculated using the equation q = mc?T, where m is the mass of the sample, c is the specific heat, and ?T is the temperature change. Heat is a measurement, it doesn't have an independent existence. An object does not possess heat, an object possesses internal energy.
If object A travelling at 5m/s hits a stationary object B, the speed of object A reduces to zero, and the speed of B increases to 5m/s. Something called "speed" has not literally moved from A to B. Speed is a measurement, not something that has an independent existence
If object A at 30deg C touches object B at 20deg C, the temperature of object A will reduce and the temperature of object B will increase. Something called "heat" has not literally moved from A to B. Heat is a measurement, not something that has an independent existence
The statement "The heat moves from one body to the other" is not incorrect as a figure of speech.
That's not a claim of mine.
I don't see a circularity in that. If P then Q, if ~P then ~Q.
Quoting RussellA
Sure. But not sure what your point is here. I don't see how this is a problem specific to Kripke's account, if that is what you are thinking.
Also note that the lectern has other properties that are not necessary - Kripke points out it might have been in the other room.
Quoting RussellA
I think this wrong, for reasons already given. I also think this quibbling is pointless. Have another read of my rejection of Kripke's argument at .
Quoting RussellA
This is a confused argument. Momentum would be conserved across the collision, and if it were frictionless and head-on, and B were stationary, the velocity would be literally transferred to B - think of a Newton's Cradle. The same point can be made using energy instead of momentum. Energy moves from one object to the other.
'If there is smoke then there is fire'. 'If there is not smoke then there is not fire' does not seem to follow.
Perhaps you meant If P then Q, if ~Q then ~P .
It wasn't meant to. it was showing that the structure is not circular.
So, if it was valid it would be circular, otherwise not?
How do we determine that two rigid designators refer to the same thing.
Kripke wrote: "To state the view succinctly: we use both the terms heat and the motion of molecules as rigid designators for a certain external phenomenon. Since heat is in fact the motion of molecules, and the designators are rigid, by the argument I have given here, it is going to be necessary that heat is the motion of molecules."
Therefore, as Kripke is saying that heat is a rigid designator, the motion of molecules is a rigid designator, and since "since heat is in fact the motion of molecules", the two rigid designators must be referring to the same thing.
As you wrote: "He provokes the difficult argument that it is necessary that heat is molecular kinetic energy, but contingent that we happen to feel this as the sensation we call heat."
When Kripke refers to "heat", is he referring to what is in the world as molecular kinetic energy, or is he referring to what is in the mind as the sensation of heat ?
As regards heat as the sensation of heat, Kripke writes:
1) "Martians, who do indeed get the very sensation that we call the sensation of heat"
2) "Then these creatures could be such that they were insensitive to heat; they did not feel it in the way we do; but on the other hand, they felt cold in much the same way that we feel heat."
As regards heat is the motion of molecules, Kripke writes
1) "First, imagine it inhabited by no creatures at all: then there is no one to feel any sensations of heat. But we would not say that under such circumstances it would necessarily be the case that heat did not exist; we would say that heat might have existed, for example, if there were fires that heated up the air."
If "heat" refers to the sensation of heat in the mind, then how can there be identity between something that exists in the mind and something that exists in the world, the motion of molecules.
If "heat" refers to the motion of molecules, there are two possibilities: i) heat is no more than the motion of molecules, heat is a synonym for the motion of molecules, and therefore "heat is the motion of molecules" is an analytic statement and known a priori, ii) heat exists over and above the motion of molecules, heat exists independently of the motion of molecules, and therefore heat would exist even if there were no molecules in motion, in which case heat could only be discovered a posteriori. As current scientific theory does not propose that heat exists independently of the motion of molecules, heat must be a synonym for the motion of molecules, a case of self-identity. As Kripke said "What properties, aside from trivial ones like self-identity"
Therefore, the statement "heat is the motion of molecules" is either an analytic statement known a priori or requires an understanding as to how there can be an identity between something in the mind and something in the world.
Kripke's misuse of "necessary" is very well displayed at the point where he states "if the table is not made of ice, it is necessarily not made of ice". By using the conditional "if...", possibility is implied. So necessity here, only follows from the fulfillment of that one possibility. This makes "necessary" contingent, which is a category mistake.
He employs this fallacy (category mistake) as a sophistic trick to bring "necessary" into the category of "contingent". Whether or not the table is made of ice is always a human judgement. And a human judgement is intrinsically fallible, therefore does not provide the conditions required for "necessary".
So propositions like "the table is made of ice", and "the table is not made of ice" can never express anything which is necessary, because those statement are contingent on that empirical judgement which is fallible. Kripke repositions the contingency of such a proposition, from the judgement to the conditional "if...then necessarily...", to create the illusion that the conditions of necessity may have been fulfilled. However, the proposition is conditional therefore the conditions have not been fulfilled, and "necessary" is just an illusion created by him.
Then Kripke proceeds to misuse "necessary", as in your example.
Yes, human judgement must come into it.
Suppose this lectern is made of wood and is in the lecture theatre
Kripke has made the judgement that being made of wood might be an essential property of this lectern, and being in a different room is a non-essential property. Someone else could have made the opposite judgement, that being made of wood is a non-essential property whilst which room this lectern is in is an essential property.
But keeping with Kripke's judgement that being made of wood might be essential property of this lectern..
Someone could say that there is a possible world where this lectern could have been made of plastic, which is highly likely. However, there can be many definitions of "possible worlds", but this is not what Kripke's means by "possible world". For Kripke, a "possible world" is a world in which this lectern keeps its essential properties.
Keeping with Kripke's understanding of "possible world" as a world where this lectern keeps its essential properties.
Therefore, this lectern, which is made of wood, has the essential property of being made of wood, meaning that in all possible worlds it is still made of wood. This lectern is necessarily made of wood in all possible worlds, because by definition, if this lectern is made of wood in the actual world it must also be made of wood in all possible worlds.
So, the statement "this lectern, which is made of wood in this actual world, must necessarily be made of wood in all possible worlds" is contingent first on Kripke's judgement that being made of wood might be an essential property of this lectern and second on Kripke's understanding of a possible world as one in which this lectern keeps its essential properties.
Trouble is, we talked of heat well before we described it as the motion of molecules. And not just the sensation, but what was needed to kindle a fire and boil the kettle and make winter bearable. Not just the sensation.
Being made of wood is not essential of being a lectern. However, if we are talking about a particular thing, that lectern in particular, then every property is essential to it being the very thing which it is. That is the law of identity. So when we talk about particulars, every property is essential, and there is no need to make the arbitrary judgement of which properties are essential.
Quoting RussellA
This is where things get difficult for Kripke. By the law of identity all properties of a particular individual are essential properties. So if he wants to bring a particular into a possible world (where a particular could have properties other than it does), he violates the law of identity. This is why the standard, traditional procedure, is to represent the particular object as a logical subject. Then we maintain the separation between the logical subject, which may partake of may possibilities, and the material object which by the law of identity is what it is, necessarily, and therefore allows of no other possibilities
Quoting RussellA
The problem I see here is the judgement factor. That particular lectern is judged to be made of wood. That is a human judgement which could conceivably be wrong. So we cannot say that it is necessarily made of wood, that might be a mistaken judgement. However, we can represent that particular object as a subject, named "a wooden lectern". This subject is necessarily made of wood, because it is stipulated. Then we can place that subject, a wooden lectern", in whatever possible world we like, where it is always necessarily made of wood. The point here being that we make a distinction between the material object which is always exactly what it is (by the law of identity), and what we say of that object. The possible worlds consist of what we say. This allows for the reality that we may be mistaken in our judgement of what is a property of any particular object.
Again, this odd interpretation has the result that when one says the lectern might have been in the other room, one is talking about a different lectern.
Quoting Metaphysician Undercover
this is were Meta goes amiss.
No, you would be talking erroneously about the lectern in question. It's not the case that it might have been in a room other than the one it is in, unless you mean that it might have been earlier or might be later in another room.
As if "The lectern might have been in the other room" were false.
Often, the cause of an effect is given the same name as the effect
Yes, I can experience a sensation in my mind such as pain. My pain as an effect in the mind may have a cause in the world. I see a thistle, and believe that the thistle is the cause of my pain. I need to know nothing about the nature of thistles in order to believe that the thistle was the cause of my pain. In Kant's terms, the thistle is a thing-in-itself.
Often, the cause of an effect is given the same name as the effect. For example, the sensation of red when looking at a red postbox. The sensation of sweet when having a sweet after dinner. The sensation of heat from a hot radiator. The sensation of a burning smell from a burning bonfire. The sensation of a bitter taste from an Angostura Bitter.
The fact that the name of an effect is the same as the name of its cause does not mean that the effect and its cause are the same thing.
That's right, as it should be, as Janus indicates. That's because if the lectern we are talking about is in the other room, it is a different lectern from the one we know to be in this room, necessarily. "Necessarily" here is supported by the law of identity which is the premise which forces this conclusion.. Just like, if the lectern we're talking about is made of plastic, when this one we know to be made of wood, we would necessarily be talking about a different lectern.
That's how the law of identity works to prevent sophistry. It's very intuitive, and restrict us to saying things we truly believe, while sophistry is a matter of saying deceptive things. You don't truly believe that the lectern which is in this room might be in the other room, do you?
Yes, "might have been" implies a different time, and so we can allow that the lectern might have been in a different room, at a different time, but to use "might have been" to imply at the same time, is just deceptive speaking.
Quoting Banno
Yes, it's false because it is deceptive speaking. It's deceptive speaking because it employs ambiguity, as "might have been" implies a different time, whereby the described possibility would be acceptable, but it is used to mean at the same time, whereby the described possibility is unacceptable (by the law of identity).
That's why I asked, do you really believe that the lectern which is in this room might be in the other room. If not, then what are you saying with "might have been"?
Actually, its a demonstration of the different categories of truth, and how it is his wish to distinguish them, beginning at the bottom of pg176. It isnt about different lecterns; its about different ways of knowing about one lectern.
He says, We can certainly talk about this very lectern and whether it can have certain properties which in fact it does not have. For example, it could have been in another room from the one it was in fact in, even at this very time, but it could not have been made from the very beginning from water frozen into ice.
Here hes saying this lectern cannot have any material property other than the essential one it does, but we can still talk about it as if space were one of its properties. Which is what we do when we say this lectern could have been in another room, but it couldnt be made of ice.
One of the properties which in fact it does not have, regarding the lectern in particular and objects in general, is, of course, space. And, as hinted, so too is time a property objects in general cannot have.
Thus is the conflict incurred between Kripkes categories of truth and Russells so-called scope of description, re: this/that modal distinctions, whereby a necessary identity statement regarding THIS thing, that THIS thing cannot be in THAT place on the one hand, in juxtaposition to the contradictory attribution of space and time as properties, on the other.
Logical statements are validated by themselves, but their proofs are in experience alone. It is far easier to prove THIS thing can be in THAT place and remain THIS thing, then to prove THIS thing in THAT place is not THIS thing.
Quoting Metaphysician Undercover
The law of identity
There is something in front of me. It has many properties: being made of wood, brown in colour, being in a lecture room, being 1.5m in height, not made of ice, etc. It must be true as @Metaphysician says: "By the law of identity all properties of a particular individual are essential properties". In the sense that all the properties this thing has are essential to making this thing, in that if this thing had different properties it would be a different thing. If this thing lost even one molecule, it would be a different thing. It must be true as @Banno wrote: "If the lectern before us were made of plastic instead of wood, it would be a different lectern to the wooden one that is actually before us."
We judge some properties of an object more essential than others
However, this would be inconvenient for humans in navigating their world if everything they saw in the world was continually changing. Therefore, for convenience, humans judge certain properties more essential than others. For example, one person could judge that being made of wood was more essential to being a lectern, and another person could judge that being in a lecture room was more essential to being a lectern. There is no correct judgement, it is a matter of personal judgement. It must be true as @Metaphysician wrote: "Being made of wood is not essential of being a lectern."
Kripke and Rigid Desgnators
Kripke wrote: i) "What do I mean by rigid designator? I mean a term that designates the same object in all possible worlds.", ii) "We can talk about this very object, and whether it could have had certain properties which it does not in fact have. For example, it could have been in another room from the room it in fact is in, even at this very time, but it could not have been made from the very beginning from water frozen into ice."
In order to make sense of objects in the world, those properties judged more essential than others required to maintain the identity of an object, are called by Kripke "rigid designators". Rigid designators are defined by personal judgement. For example, let a rigid designator of a lectern be "being made of wood", though it could equally well have been "being in a lecture room". As we have judged being made of wood is an essential property of a lectern, by definition, being made of wood becomes a property of a lectern.
It follows that as "being made of wood" is now part of the definition of a lectern. If I see an object that is not made of wood, then by definition it is not a lectern. It must be true as @Metaphysician wrote: "So we cannot say that it is necessarily made of wood, that might be a mistaken judgement". Because this definition of lectern doesn't include being in a lecture room, as a lectern may or may not be in a lecture room, the lectern is not necessarily in a lecture room.
Definitions are necessarily true a priori
Kripke wrote: i) "So we have to say that though we cannot know a priori whether this table was made of ice or not, given that it is not made of ice, it is necessarily not made of ice. " ii) "For example, being made of wood, and not of ice, might be an essential property of this lectern."
But what is a "lectern". What does "lectern" mean. The meaning of words cannot come empirically from observation of the world, in that, if I look at the world and see on the one hand a group of charging elephants and on the other hand a stand made of wood in a lecture room, it would be impossible to know a posteriori which of these "lectern" refers to. The meaning of "lectern" can only be determined a priori either from a dictionary or similar or from use within language. Therefore, the meaning of "lectern" is a priori and necessary.
Therefore, in Kripke's statement "being made of wood..........might be an essential property of this lectern.", "this lectern" may be replaced by "this something that is known a priori as being made of wood". This gives the statement "being made of wood..........might be an essential property of this something that is known a priori as being made of wood", which is an analytic statement, and from the law of identity, being made of wood is necessarily being made of wood.
Conclusion
Therefore, as a lectern has been defined as being made of wood, if this lectern is made of wood, then this lectern is necessarily made of wood. Such identity statements are therefore necessary and a priori.
This is the difficulty. The law of identity allows that a thing could continue to be the same thing, despite undergoing change. That is the temporal extension of a thing. So the status of "thing" simply implies some form of temporal continuity. From this perspective we understand "change" as relative to the supposed temporal continuity (Newton's first law for example). But this assumed temporal continuity is inductive in nature, and it cannot actually be proven due to the reality of change which is happening everywhere, to everything, all the time. Therefore the law of identity, along with the prerequisite assumption of "things" (a "thing" being a temporal continuity of sameness) presupposes without justification the necessary existence of things, and the necessity of temporal continuity of sameness. Because of this, it is fundamentally defective.
This is why Hegel attacked the law of identity, giving logical priority to "becoming", making being and not being, and therefore the existence of actual things, simply a human judgement which we impose on the world of becoming. The idea that the existence of external objects is intuited rather than saying that the external object has real independent existence, I believe is basic to phenomenology.
That's risible.
And you continue to mix the law of identity with the identity of Indiscernibles.
But it's on par with many of you other arguments. I'll leave you to it.
Then you are now claiming that there are no properties that are not essential, and hence that differentiating essential form nonessential properties is an error.
The consequence is that any change in the properties of an individual result in a different individual.
I don't think that is going to work out well.
I'll invite you to reconsider the difference between the law of identity, A=A, and the identity of indiscernibles, that if everything true of x is true of y, x is identical with y. These are different laws.
I'll maintain that @Metaphysician Undercover is mistaken and that an object's properties may be subject to change and that it makes sense to talk of essential an non-essential attributes.
It is false; it is a mere logical possibility, nothing more than a matter of mere words.
I don't agree. He happened to use a spatial example - the lectern might have been in another room. But he might equally have used a material example such as that the lectern might have been painted pink or had his name engraved on it. These are ways in which the properties of that very lectern may have been otherwise.
But to suppose that the lectern before us may have been made of ice is to suppose that the lectern before us were a different lectern.
Kripke is not claiming that the lectern could not have any material properties other than it does have.
"The lectern might have been in the other room"
Make up your mind - is it false or is it logically possible?
I say it is a true proposition about this lectern. This very lectern might have been in the other room.
A nonsense expression. Perhaps you mean it is logically possible but not actual. Sure. It remains that "The lectern may have been in the other room" is a meaningful sentence. And it seems to be true. It is also true that the lectern is not actually in the other room. There is no contradiction between these sentences:
No, a valid distinction which you can't see apparently. Try looking beyond words, you might actually arrive at some new thoughts.
SO it's a distinction that you cannot express. :brow:
Then it's a distinction that makes no difference.
A nonsense, again. Actually, it is in this room; Possibly, it might have been in the other. That's it.
What you want to claim might be that there are consequences, including those that are both unforeseen and unforeseeable, for things being other than they are. Sure. Sorting out those consequences begins with a consistent semantics, as provided by Kripke.
Hence it remains true that
Have it your way: I see no point in arguing further against dogma, so I'll leave you to it.
Of course, but these are not properties the lectern cannot have. They do not represent the properties the lectern must have such that to not have them the lectern wouldnt be this very object. Youre talking about what it can have; hes talking about what it cannot have. If space is a property it cannot have, THIS lectern cannot be in THAT room, for then it would be in two spaces simultaneously.
Quoting Banno
These are ways that very lecterns properties are cumulative without contradiction. Add all the properties you like, but its still going to be made of wood, its still going to be in this room. As long as the subject making the statements is as well, which is tacitly understood to be the case.
Of course the lectern might be in the other room, in which case it would not be in this room. Supposing that the lectern might have been in the other room is different to supposing that it might have been in both this room and in the other room.
Quoting Mww
Sure, it's actually in this room. But it might possibly have been in the other. But if the lectern in this room were made of ice, it would be a different lectern. Being not made of ice is an essential property, being in this room, being pink and having "Kripke was here" engraved on it, inessential.
You continue to demonstrate that you have no idea what the law of identity actually states. You state your rendition as "A=A", but you continue to show that you have no idea what this represents.
Quoting Banno
Not only do you have no idea what the law of identity states, you totally misrepresent what I say. Look at the following, what I said, and please retract what you said about me above.
Quoting Metaphysician Undercover
Regardless of whether a thing changes or not, a thing is necessarily the thing which it is, by the law of identity. And, at any given point in time, all of its attributes are necessary to it being the thing that it is. Therefore all of its attributes are necessary. That is implied by the law of identity (a thing is the same as itself). If it does not actually have all the attributes which it has, it is not the same as itself. Therefore all of a thing's attributes are necessary, by the law of identity.
So I don't see anything to be gained by pursuing it further, since it is all pretty obvious until it becomes murky and there seems to be no way to definitively dispel the inevitable murkiness.
Quoting Banno
And this! I'm surprised to see you advocating essentialism.
That's what it is - a tool for working through those apparent contradictions.
Quoting Janus
Just so, as here.
Quoting Janus
Hardly. There are issues here, but if we cannot agree on the framework within which they are to be discussed, the topic cannot progress.
I have seen only stipulative resolutions to the murky aspects of identity, and frankly such resolutions seem to have no significant point and to be of little value.
But I guess it all comes down to personal tastes and interests.
2. [math]\diamond ( \neg x = y)[/math] [assume]
3. [math]\diamond (× = y)[/math] [from 1]
4. [math]\diamond (x = y) \land \diamond (\neg x = y)[/math] [from 2 and 3]
5. [math]\diamond (x = y \land \neg x = y)[/math] [from 4]
6. [math]\neg \diamond (x = y \land \neg x = y)[/math] [contradictions impossible]
7. [math](\diamond (x = y \land \neg x = y)) \land (\neg \diamond (x = y \land \neg x = y))[/math] [from 5 and 6]
8. [math]\neg \diamond (\neg x = y)[/math] [2 to 7 reductio ad absurdum]
9. [math]\Box \neg (\neg x = y)[/math] [from 8]
10 [math] \Box (x = y)[/math] [from 9]
11. [math](x = y) \to \Box (x =y)[/math] [1 to 10 conditional proof]
QED
https://www.umsu.de/trees/#(x=y)~5~8(x=y)
2. [math]\Diamond (x = y)[/math] [from 1]
3. [math] \neg \Diamond (x = y \land \neg x = y)[/math] [LNC]
4. [math]\Box \neg (x = y \land \neg x = y)[/math] [from 3]
5. [math] \Box (x = y \lor \neg x = y)[/math] [from 4]
6. [math]\Box (x = y) \lor \Box(\neg x = y)[/math] [from 5]
7. [math]\Box (x = y) \lor \neg \Diamond (x = y)[/math] [from 6]
8. [math]\Box (x = y)[/math] [from 2, 7]
9. [math](x = y) \to \Box (x = y)[/math] [1 to 8 conditional proof]
QED
First, thanks for the awesome link. I'll need it. Does the site also explain the rules and latest notations of natural deduction?
Second, yep, it's a tautology. Is that a bad thing? It's a property of the system as opposed to being a property of the world?
Since it's a tautology it is necessarily true, ie, true in all possible worlds. "Property of the system" if you like; it's a grammatical structure that cannot be wrong.
It follows Kripke's argument in showing that any identity is a necessary identity.
How do you think it helps here? Kripke suggests that if x=y is known by observation, then ?(x=y) is also known by observation, but @Mww continues to deny this, claiming despite the examples given, that x=y is never known by observation but is always a priori. I don't see that this will convince him otherwise. No helping some folk.
Edit: Try this one: https://www.umsu.de/trees/#(x=y)~5~8(x=y)||universality . S5 is easier to follow.. Simple accessibility relations. w and v being possible worlds.
Observationally x = y [math]\to \Diamond (x = y)[/math]
If, as Mww claims [math]\neg ((x = y) \to \Box (x = y))[/math] then [math]\Diamond (x = y \land \neg x = y)[/math], but [math](x = y \land \neg x = y)[/math] is a contradiction (impossible) i.e. [math]\neg \Diamond (x = y \land \neg x = y)[/math]
Ergo, reductio ad absurdum, [math](x = y) \to \Box (x = y)[/math].
How can that be ?
In logic, the law of identity states that each thing is identical with itself. Gottfried Wilhelm Leibniz expressed it as "Everything is what it is". Wilhelm Wundt credits Gottfried Leibniz with the symbolic formulation, "A is A".
Object A, from the law of identity, is identical with itself.
I am taking object A as something that exists in the world, not as the name "object A". Object A and "object A" are different things. Object A exists in the world and "object A" exists in the mind. "Object A" is the name for object A.
All the properties object A has are necessary for object A to be object A, and all the properties object A has are essential for object A to be object A.
If object A changes into Object B over time, even if it has lost only one molecule, then object B cannot be the same as object A.
Are you content with this account? Is the property of having writ that post essential to your being who you are? Might you have not written it, yet remained RussellA?
Quoting Banno
I agree that Kripke has put forward his case that true identity statements are necessary before introducing the examples of names, heat and my pain. However, if the examples he uses of true necessary identity statements are not in fact true necessary identity statements, then this casts doubt on the case he has previously made.
For example, he is using the word "heat" in two different ways, and when he writes "heat is the motion of molecules", it is unclear in what sense he is using the word "heat". "Heat" can refer to the cause and "heat" can also refer to the effect.
Specifically, Kripke gives an example of a true necessary identity statement as "heat is the motion of molecules"
Heat is the transfer of energy between objects due to a temperature difference between them. Bodies don't contain heat.
Problem one - as regards heat transfer by convection, a body having internal energy moves from location A to location B. As bodies don't contain heat, how can heat be the motion of molecules ?
Problem two - as regards heat transfer by conduction and radiation, no molecules move from hotter object A to cooler object B. How can heat move from A to B, if heat is molecules in motion, and no molecules move from A to B ?
On logic ..
. Notwithstanding, there lies so seductive a charm in the possession of a specious art like this ( ) any attempt to employ it as an instrument (organon) in order to extend and enlarge the range of our knowledge must end in mere prating; any one being able to maintain or oppose, with some appearance of truth, any single assertion whatever. Such instruction is quite unbecoming the dignity of philosophy
It is possible for there to be a lectern in another room. It is possible for a lectern to be anywhere. According to the example in question, this very object, in the room it is in fact in, even at this very time cannot possibly be in any other room.
Try as I might, some folks I just cant help. Horse/water kinda thing, I guess.
And yet the lectern might have been in the other room, you might not have written your reply, Kant might have gone into fishing rather than philosophy... all of these things might have happened. They didn't, but they may have.
Recent modal logic gives us a way to deal with such suppositions. What you have proposed, does not.
In this possible world, the lectern is in this room, not in the other room. In some other possible world, it is otherwise, without contradiction.
Logic has advanced somewhat since Kant.
Yes, each thing is identical with itself, everything is what it is. And, things are changing as time passes. Therefore being identical with itself, or being what it is, means changing as time passes. There is no inconsistency between the two.
If it were the case that when a thing changes it is no longer the thing that it is, then an object could not have any temporal extension. At every moment, as time passes, and the object changes, it would become a new object. So, in order that an object can have temporal extension, and maintain tis identity as the thing which it is, while time passes and it also changes, Aristotle proposed the law of identity. This is the reason for his "hylomorphism", a material thing has two aspects, form and matter. The form is changing (actual) and the matter stays the same (potential).
Quoting RussellA
This is where we have to be careful not to be fooled by sophistry. When object A requires a new description (because it's properties change due to the passing of time), this does not mean that it has become a different object. That's the very reason for the law of identity, to allow us to say that a thing maintains its identity as the same thing, which it is, despite changing as time passes.
Without this law, all sorts of logical sophistry ensues. Instead of being within the object itself, as is the case with the law of identity (as the same as itself), an object's identity is what we say about a thing. And as Banno is demonstrating, we can say very strange things about objects, and show how these strange things are consistent with our axioms of identity. Of course, when the fundamental axiom is that the object's identity is what we say about it, rather than what it is in itself, we can make its identity whatever we want, and there is no truth to the matter.
Quoting Banno
"Declined" is probably a better word to use here. Look at the confused mess of quantum mechanics as an example.
Yes. I'm not saying that I have Dissociative Identity Disorder, but there are two distinct RussellA's.
There is the RussellA that exists in the world as fundamental particles and forces, and whose identity is constantly changing. At each moment in time, RussellA's properties are both necessary and essential in order for RussellA to be identical with itself. Even if RussellA loses only one fundamental particle, then RussellA's identity would have changed
There is also the "RussellA" that exists on this Forum and whose identity stays the same over time. A "RussellA" that exists in society, exists in the mind and exists in language. "RussellA" has what Kripke calls rigid designators, ensuring that "RussellA's" identity remains the same even in all possible worlds. "RussellA" has necessary and essential properties. What these are no one knows for certain, but I believe that I have them, even if I don't know what they are. I might have had to go shopping, not had time to write this post, yet remained "RussellA". However, RussellA would inevitably have changed, gained weight, lost some more hair, etc.
If I had not written this post, I would still be "RussellA" but I wouldn't be RussellA.
Nobody cares about what might have happened, when they are only affected by what does.
Quoting Banno
Correct. Not much need to deal with might-have-beens. Psychologists excepted, but (sorry, Isaac) no proper philosopher cares about them anyway.
Quoting Banno
Logic has changed. Whether it has advanced, is questionable. All the basic conceptions of modern modal logic are already contained in Kantian metaphysics, and have been classified as such since Aristotle.
Admit it, Good Sir: youre grasping at straws. All the cool stuff has already been done, and you missed the boat.
A person can maintain their identity as the same thing yet at the same time have different properties.
But how can an object maintain its identity as the same thing yet at the same time have different properties ?
Permit me to take a stab at that.
Properties
1. Essential i.e. critical to identity e.g. the 3 sides + the 3 angles of a triangle.
2. Incidental i.e. not critical to identity e.g. the color of the triangle above.
There are objects in the world and there are "objects" in the mind
Assume in the world is something that has a set of properties: being in a flat plane, three straight sides, having three angles, 10cm large, colour green, rotated at 45 degrees, located in Paris, made of paper, makes no sound, has no smell, etc
What determines that some of these properties are essential to the identity of this something and some properties are incidental ? A mind-independent world cannot make this determination, it can only be made by a person. However, in the event that one person judges that colour is an essential property whilst another person judges that colour is an incidental property, how is it determined who is correct ?
If it is a person who is judging which properties are essential and which incidental, then they are not referring to something that exists in the world as a set of properties, but they are referring to something that exists in the mind as a concept.
I agree that concepts in the mind maintain their identity even though different instantiations of the concept in the world may be associated with different properties.
Hrmm... I think I'd say logic has changed considerably since Kant, and I'd say that it's for the better too. While Kant has the modalities as categories I'd say that's a problem with his logic -- Camus even makes a joke about that in The Myth of Sisyphus, so I always presumed it was understood that the modal categories are kind of funny in that they don't really spell out either a relation between objects (causality) or properties of objects (quality and quantity), but rather pick out judgments of a certain kind.
Modal logic is more specific than Kant's.
Furthermore, the categories are part of a transcendental logic, right? So we can easily see Kripke as contributing to logic, as such, to use Kant's distinctions. This is a pure logic rather than a transcendental logic. At least, this is how I'd put things. (The difference between logic as such and transcendental logic is... not easy to spell out. If this doesn't click, then this is probably as clear as I can be without more work.)
I'll try to illustrate with examples.
1. Goals: If my goal is finding the area of a triangle then I'd need to focus on the angles and sides (how many there are and their values).
2. Brains: Properties are abstractions and to home in on those properties that are essential takes brains. Everybody saw objects fall to the earth, the moon traverse the night sky, but it took a Newton to realize that these two were the same thing.
3. Circumstances: A biologist may be interested in a tiger's penis :rofl: but if you were to encounter one in the forest, your eyes would immediately zoom in on its claws and fangs.
It looks like I consider essential is contextual - it depends on the situation. Do I mean that there are no essential properties, a sine qua non for classification/categorization/identification? At this point, I call upon the all-too-familiar phrase ceteris paribus - the world is chaotic, but every once in a while there's a lull in the storm and when we place (an) object(s) in that quiet zone, its/their true essence comes into view.
You wouldnt be alone.
Quoting Moliere
Maybe; dunno. Specific in what way? As I said in another thread one division containing two books containing five chapters containing eight sections containing 179 pages ..and an appendix. All as only one of two divisions in an rather thorough exposition of a very specific human logical functionality.
Cant help but think the moderns have that exposition, as the ground of their own presuppositions. Likely, since Kripke actually begins this article with a reference to it.
But this isnt the place for Kant himself, so ..
Just in the way that multiple people can work with it, understand it, communicate about it, and even -- sometimes -- use it. Speaking about Kant we don't really use his categories as much as argue whether or not they are necessary for all the other stuff we do. It's a confusing logic, even if it is ultimately correct. With Kant's categories he is so certain that we know what he's talking about that he says we already know what he's saying.
Yet, here we are -- reading a transcript of a talk about different interpretations of modalities.
Not that one couldn't work this into Kant's project, necessarily... that's why I posited the as-such/transcendental distinction between different notions of logic. Especially because @Banno was emphasizing how this is just a way of talking, rather than a metaphysics. I think transcendental logic gets close to metaphysics in the wider sense of the philosophical tradition, while demarcating what is and isn't metaphysics by Kant's philosophy.
Ok; all good .
Quoting Moliere
.except for that. He was pretty certain we commoners hadnt a clue what he was talking about, even though he says every one of us is doing what his theory suggests. But I see what you mean: after his explanation, we can say oh hell yeah, thats right!!!!
As you mentioned, [math](x = y) \to \Box (x = y)[/math] is a tautology in the sense its truth is independent of reality - it's, some would say, just the way the system works.
[quote=CPR Pluhar translation, A83/B109]In this treatise I deliberately refrain from offering definitions of these categories, even though I may possess them. I shall hereafter dissect these concepts only to a degree adequate for the doctrine of method that I here produce. Whereas definitions of the categories could rightly be demanded of me in a system of pure reason, here they would only make us lose sight of the main point of the inquiry. For they would give rise to doubts and charges that we may readily relegate to another activity without in any way detracting from our essential aim. Still, from what little I have mentioned about this, we can see distinctly that a complete lexicon with all the requisite explications not only is possible but could easily be brought about. The compartments are now at hand. They only need to be filled in; and a systematic [transcendental] topic, such as the present one, will make it difficult to miss the place where each concept properly belongs, and at the same time will make it easy to notice any place that is still empty.
[quote]
Quoting Britannica
I think the physics here is misguided. We might consider other examples. For instance, that water is H?O was found to be the case by experiment. Yet in any possible world, if what is called "water" is not H?O, then in that world "water" refers to something else.
We can plug this in to (x=y)??(x=y), with "water" substituted for x and "H?O" substituted for "y".
Hence, and as it is more commonly phrased, water is necessarily H?O. Moreover, that water is H?O is known by investigating how the world is, not by examining the terms involved.
Well, yes, although I would phrase this more specifically, as that logic sets out how we can talk about stuff while maintaining consistency. So if one grants the use of the predicate "=" to be that the thing on the left is the very same as the thing on the right, one must grant (x=y)??(x=y).
Quoting Agent Smith
Again, yes, although one should avoid the temptation to deny the consequences for how we talk. So the discovery that water = H?O leads us to conclude that necessarily, water = H?O, or leave consistency behind.
SEP lists four theories. I favour the third, although the second and fourth have merit. The first is subject to the criticisms mentioned in this thread.
So let v be a valuation that assigns either T or F to the the propositional variables of predicate calculus ( the set of formulas ? ), then
Quoting Open Logic
There are variations that attempt to deal with non-extensional contexts. One might seem the aim here as sorting out what can be said without contradiction.
When the object "requires a new description", it is because it has changed, therefore it's not "at the same time". It's not at the same time, it's over a duration of time. A thing changes, yet continues to be the same thing, therefore it has contradicting properties, but not at the same time.
However we can write a short piece of code for a run-of-the-mill PC, e.g. it can just include a modus ponens subroutine, and it'll churn out truths like nobody's business; all that with zero semantics ability (computers allegedly don't have semantic understanding though they're annoying grammar Nazis). I believe that was the whole point of logic.
Quoting Banno
The question is to what extent is scientific language literal or metaphorical. To what extent is Kripke's language literal or metaphorical.
I believe "move" is being used as a figure of speech, not that heat literally moves.
You are by-passing the question as to in what sense does heat, which doesn't exist in a body, and is a measurement, move from one body to another ?
It depends of which properties are essential for an object to be the same object.
It it is judged that location is an essential property of an object, then if the object changes location then by definition the object has changed. For example, a 1.5m tall piece of wood in a lecture room is a lectern, on a bonfire it is kindling.
If it is judged that location is not an essential property of an object, if the object changes location then by definition it is still the same object. For example, a euro coin in Brussels is money, in Athens it is still money.
No definition is correct, no choice of essential property is correct, as they are based on human judgement. Kripke's rigid designators are also matters of personal judgement.
The need for this judgement, as to which properties are essential and which are accidental, is what is eliminated by the law of identity. This law puts the identity of the thing within the thing itself, therefore the thing's identity is not based in any human judgement of essential properties.
This forms the difference between the identity of a thing, and the identity of a type. A type is identified by essential properties, " a lectern must be... in order to be a lectern", for example. A statement of essential properties is a statement of the necessary criteria for a type. It cannot be a statement of the necessary criteria for a particular thing, because it's a human judgement, and human judgements are fallible. Even if we say something like "the essential properties of this particular lectern are...", all we are doing is making "this particular lectern" into a type. That is because "essential properties" is what defines a type.
So the best we can do as human beings is to set the criteria for a type, by naming essential properties, and judge the particular as to whether it fulfills the conditions of that type. If we desire to set the conditions for a particular, we need to name also the accidentals because a particular consists not only of essential properties (of its type), bit also the accidentals (of that particular). But the accidentals change at every passing moment, and we cannot know them all, so our attempts to identify a particular in this way, are not a true identity.
That is why we must insist that any claim to know the identity of a particular, made by human beings, is mere sophistry. All these human beings are doing is naming a type (essential properties), and claiming that there is only one of this type. But that is not really an instance of producing the identity of an individual. To produce the identity of an individual would require naming all the accidentals.
If "this lectern" is a type, and as types are usually thought to be universals, who is correct, the Realist, the Nominalist or the Conceptualist ?
The Realist thinking that "this lectern" exists in a mind-independent world, the Nominalist who believes that "this lectern" only exists as one particular instantiation at one moment in time or the Conceptualist who understands "this lectern" as a concept existing in the mind only.
It seems Kripke's form of Realism was more linguistic. The reference of "this lectern" is fixed by an act of "initial baptism" which designates a very real physical object with an observable property, such as "this lectern is made of wood". However, the meaning of this expression can evolve over time and even change completely, but what establishes the reality of the expression "this lectern is made of wood" is the existence of a continuous causal chain linked to the initial baptism. Language maintains its stability, even if the meaning of the expressions it uses change with time.
IE, for Kripke's causal theory, expressions within language may start by corresponding with the world, but as time goes by, may correspond less with what initially baptised them as long as they maintain a coherence within the linguistic contexts within which they are used.
Instead of having the particular comonad known as 'universal quantification' and the particular monad known as' existential quantification' which already give first order logic a canonical and a priori definition of "necessity" and "possibility", S4 has a weakly defined arbitrary comonad called "necessity" and an arbitrary monad called "possibility", making it weaker than first order logic.
But gven that modern type theories permit arbitrary definitions of monadic structure in addition to explicitly possessing quantifiers whose use is optional, what justifies philosophers continuing the study of modal logic with it's antiquated and impoverished syntax and weaker modes of justification that ironically encourage misleading over-interpretation by philosophers?
In my understanding, what gives Modal logic continued relevance is the usefulness of Kripke Semantics, i.e. the intuitive and useful concept of an accessibility graph of possible worlds together with propositions that pick out subsets of those worlds, a semantics which the syntax of Modal logic succinctly describes.
But if the semantics of modal logic are merely regarded as the predetermined outcome of 'real' modal operators of an underlying modal logic, as seems to be indicated when philosophers attempt to justify their abstract modal reasoning with respect to an assumed definition of the modal operators, then i think Modal logic is either obsolete, and misleading.
Ironically, I think where Kripke Semantics shines is when it is used descriptively in a data-driven fashion to chart one's present knowledge of possible worlds, without appealing to the necessary implications of a dubious modal operator. For modern logic handles reasoning from dubious assumptions in a much clearer, richer and flexible fashion.
The question is whether molecules moving is the very same as heat. Of course heat exists in a body and moves from one object to another, quite literally, as the movement of the molecules involved averages out. Reframing this in terms of metaphor is "by-passing the question".
"This lectern" is a demonstrative, not a type. "Lectern" would be a type.
What I said, is that if "this lectern" is identified by essential properties, then "this lectern refers to a type rather than a particular. That is because types are identified by essential properties, not particulars. Each accidental property is essential to the identity of a particular.
Quoting RussellA
The problem is that "this" is demonstrative, as says. It does not serve as an identity. And when when that demonstrative refers to "lectern" it only identifies a type. So if Kripke points to an object and says "this lectern", he has said that the object pointed to, is that type.
The identity of the thing is within the thing itself, as indicated by the law of identity. So identifying an object as a type does not provide the object's true identity. And, if someone moved to identity all the essential properties of the named thing (the properties which make the thing the very thing which it is), they would have to name all the accidentals. The accidentals are what make a particular particular. Naming essentials always results only in a defined type, not a particular. Therefore we cannot produce the identity of a particular lectern by naming essentials, we would only produce a type of lectern.
Your capacity to misunderstand continues to astonish.
"This lectern" is a rigid designator. It picks out that specific individual in any possible world in which it exits.
"Lecterns such as this" might pick out a type.
We've already explained to you why this cannot be the case. It is a false premise. Now I've moved on from that, to describe the difference between a particular and a type, which follows from proper employment of the law of identity.
I'll leave you to it, then.
In fact, the scientific discovery is not "water is H?O", but that the substance (whether liquid, solid or gas) we often call "water" we often detect H?O molecules. Additionally, that substance we call water is not just H?O molecules, but made up of multitude of compounds, mineral, ion, etc. Not only it is made up of a multitude of different molecules, but that composition can change from thing to thing we call or refer to as "water". So, when any one refers "water", am I referring to only H?O, or all of molecules that make up any given thing called "water"? Due to multiple uses of "water", and multiple things we use "water" to refer to or could refer to, it is an error to say "water is H?O" is discover scientically. Lastly, could we say that "some water wasn't H?O". Yes, in fact we can and do say this, D?O is called "heavy water" is the scientific community.
So, what is Kripke's error in this example? I believe he ignores the common uses of the word of "water" along with what actually science discovers about "water". What use he has in mind for "water" is how we use the word(symbol) "H?O"; thus, what he is expressing is "H?O is H?O" which is not an a posteriori necessity.
Does this throw some doubt on Kripke's philosophical theory, or just show what he is saying is just trivial, or both?
Quoting Richard B
I agree with @Richard B.
Kripke also wrote: Heat is the motion of molecules.
Wikipedia - Heat
A thermodynamic system does not contain heat.
www.britannica.com/science/heat
It is incorrect to speak of the heat in a body, because heat is restricted to energy being transferred. Energy stored in a body is not heat
www.quora.com/Does-heat-exist-or-is-it-just-another-defined-quantity-like-energy
Mark Barton - PhD physicist with University of Glasgow
"Heat" is a noun and is spoken of as a substance, even in technical language, but it's a misnomer. Strictly heat doesn't exist, it happens: it's the process of energy moving from one system to another via random microscopic interactions.
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/heat.html
Heat may be defined as energy in transit from a high temperature object to a lower temperature object. An object does not possess "heat"; the appropriate term for the microscopic energy in an object is internal energy. In warning teachers and students alike about the pitfalls of misusing the word "heat", Mark Zemansky advises: Don't refer to the "heat in a body", or say "this object has twice as much heat as that body".
https://van.physics.illinois.edu/ask/listing/1838
In formal scientific usage, heat refers not to the total amount of that thermal energy but only to the transfer of thermal energy caused by a temperature difference between objects.
https://www.khanacademy.org/science/chemistry/thermodynamics-chemistry/internal-energy-sal/a/heat
In thermodynamics, heat has a very specific meaning that is different from how we might use the word in everyday speech
Scientists define heat as thermal energy transferred between two systems at different temperatures that come in contact.
We don't talk about a cup of coffee containing heat, but we can talk about the heat transferred from the cup of hot coffee to your hand.
When the two systems are in contact, heat will be transferred through molecular collisions from the hotter system to the cooler system.
https://www.thermal-engineering.org/what-is-heat-in-physics-heat-definition/
While internal energy refers to the total energy of all the molecules within the object, heat is the amount of energy flowing from one body to another spontaneously due to their temperature difference. Heat is a form of energy, but it is energy in transit. Heat is not a property of a system. However, the transfer of energy as heat occurs at the molecular level as a result of a temperature difference.
Heat is a measurement, as is height, number, weight, etc. They don't exist independently of what they are measuring.
If there are two heaps of sand and we move sand from A to B, such that the height of A has decreased and the height of B increased, we don't say that height has literally moved from A to B.
If there are two piles of books and we move four books from A to B, such that the number of books in A has reduced and the number of books in B has increased, we don't say that the number four has literally moved from A to B.
If there are two buckets of water, and we move water from A to B, such that the weight of A has decreased and the weight of B has increased, we don't say that weight has literally moved from A to B.
Similarly, If there are two bodies and energy is transferred from A to B, such that the internal energy of A has decreased and the internal energy of B has increased, we cannot say that heat has literally moved from A to B.