Sure. The answer, at least for modal issues, is to drop talk of de re and de dicto and use diamonds and boxes and brackets to keep the scope explicit. — Banno
...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. — Shawn
Kripke, at a very young age, developed a formal semantics for modal logic, presenting a completeness theorem. — Banno
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? — frank
How can an object such as an apple, having a self-identity, have infinite possibilities ? — RussellA
“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. That’s 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 F’s to x, maybe hundreds of F’s, 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 F’s 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????? — Mww
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 that’s a category mistake. Dunno if it’s yours or not, but it works, doesn’t 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 isn’t relevant”, in order to justify the notions contained further on in it. — Mww
But still, if a theory starts out illogically, and if the circumventions are not all that valid, wouldn’t it jeopardize the whole? Kripke is just saying, if it was this way, we could say this about it. But if it couldn’t be this way, why still talk as if it could? He goes on to talk about it in a different way, that’s all.
(** existence as a predicate, reflecting on existence in possible worlds) — Mww
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. — Hanover
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? — frank
If your identity is a description or definition, then it makes no sense to say you could have become a plumber. — frank
Instead, we ought to be content in knowing that we simply cannot make any true identity statements, — Metaphysician Undercover
What's an identity statement? — frank
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). — Banno
That's because the thing itself with its true identity is understood as independent, so it appears like it's identity must be "discovered" — Metaphysician Undercover
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. — Metaphysician Undercover
The first part of this essay explains why that's problematic. How do you respond to Kripke's point? — frank
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. — Metaphysician Undercover
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). — Banno
Happy with this thread so far? — Banno
The folk who really need to read the article have just voiced their opinions, again, without addressing, and probably without even reading, the article. — Banno
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