[gjm11]

Whether 2 is true depends on how you understand "identical". For sure, if you mean something like "synonymous", then probably "identical" things are the same in all possible worlds. But if you take it broadly enough that, e.g., "consciousness is identical with something that happens in the brain" isn't false by definition then I don't see how your argument works.

I only think 1 is bullshit if you use something like the "synonymous" definition. (Can we agree that it's crazy to say that physicalism requires believing that "consciousness" just means some particular set of brain processes?)

I think your comment about 3 basically amounts to agreeing with me that physicalism doesn't say that mental states and brain states are "identical" in any sense that makes the rest of the zombie argument work.

I agree, of course, that if 1-3 are correct then "zombies are possible" implies "physicalism are wrong".

Epiphenomenalism doesn't imply that causality is false. And if consciousness is "outside of logic" then I say: so much the worse for the notion of consciousness. (But I don't see any reason why we should think consciousness is outside of logic, whether zombies are possible or not.)