metaphysical possibility ≠ logical possibility

Many people seem to think that because some concept doesn't contain a contradiction that it automatically becomes a live metaphysical possibility. It was demonstrated almost 40 years ago that this is not the case.

Naming & Necessity
http://www.amazon.com/Naming-Necessity-Saul-Kripke/dp/0674598466/ref=sr_1_1?i...

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• logic
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• metaphysical
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• atheism
• theism

[DrNSalmon]

The speaker's conclusion is correct, but he does his viewer's a serious disservice by frequently using the phrase 'logically possible' or 'logical possibility' where he means (or should mean) its dual noiton: logical *necessity*. Philosophy is done well only when it is done with care and precision. This is not philosophy done well.

[urbanelf]

@DrNSalmon Where did I say what I did not mean?

[DrNSalmon]

@urbanelf

Starting at around 2:40: "If we look at statements that are logically possible, ..." You mean if we look at statements that are logically necessary, ...

[urbanelf]

@DrNSalmon Actually, I meant what I said.  All logically possible statements are derivable a priori.

[rumpranger65]

I don't really like Kripke's ideas. I think that it seems to be the case that there is a possible world where water is not H2O.

[urbanelf]

@rumpranger65 Well, I would be interested in hearing your thoughts and how that's possible.

[jst1g]

@urbanelf (1) Nathan Salmon on youtube????

(2) Just about every professional philosopher who works on logic takes "derivable" to be a synonym from "provable." I assume you meant it a different way. That's why you and Nathan were sort of talking past each other in those previous comments.

[dbaltazarful]

Thank you, Urbanelf.

[urbanelf]

@flexicon1996 Did you know that "lol" isn't actually a word?

[mohamedbongfish]

could you please clarify this point: "the transposition of that is to say that if we can one necessary truth- one metaphysically necessary truth that cannot be derived a priori then it must be the case that logical possibility is not the same thing as metaphyiscal possibilty" and how it follows from what you say before it