Re: Is there an error in Van Fraassen's paper?

On Sep 7, 2:48 pm, herbzet <herb...@xxxxxxxxx> wrote:
herbzet wrote:
I don't see how he can at once assert that they necessitate each other,
and that they necessitate a contradiction for any truth-assignment to Y..

Not that that is a priori impossible:

Let A be a contradiction and B be a contradiction.

The A <-> B is true but A & B is false.

--
hz

He of course believes that if Y does not have a truth value then it is
not true. But then it is exactly what it says. Therefore it is true.

But I think he failed to substantiate it with the asumption that Y and
(T(~Y) v . ~T(Y) & ~T(~Y)) necessiate each other. A necessitates B
means that whenever A s true then B is true. For non-bivalent logics
necessitation is NOT equivalent to implication. I just wonder what I
have missed.


.

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