But if this is so then given the behaviour (or brain processes), consciousness by definition is present. Thus it necessarily follows that p-zombies are necessarily logically incoherent.
Another way of putting this is that the logical possibility of p-zombies begs the question of materialism.
You see?
Yes, I do see, Ian. What I see also is your apparent co-opting of my favorite criticism of the p-zombie argument and turning it on its head.
Remember where p-zombies came from. The concept of p-zombies arose from neo-dualists like David Chalmers, one of the biggest proponents of the p-zombie argument. The whole point of p-zombies as a thought experiment is to demonstrate that materialism is false.
In order to demonstrate that materialism is false using p-zombies, the proponent must in fact begin with the given assumption that materialism is true. This is because the p-zombie argument made by dualists is a proof by contradiction. To prove an assumption is false by contradiction, you must begin with assuming it is true. Basic logic.
Thus, your observation that materialists demonstrating the logical impossibility of p-zombies are begging the question of materialism is trivial. Of course they are begging the question. So are dualists who try to assert that p-zombies refute materialism. They define p-zombies such that they are exactly like conscious humans, except for some indefinable, ineffable quality of consciousness that cannot be material; they beg the question of dualism being true. Materialists scoffing at p-zombies are merely pointing out that the p-zombie argument
as a refutation of materialism is wearing no clothes. You have just co-opted some materialists' criticism of p-zombies as a refutation of materialism and turned it into a criticism of materialism. You win, Ian, because that really is interesting.
The p-zombie argument fails for the very reason Pixy gives, which is one I gave in so many words in my many exchanges with Win. P-zombies who behave in every respect as if they are conscious and who believe themselves to be conscious, are in fact conscious by any materialist definition of consciousness (that is how Win defined them, BTW, but he steadfastly denied that they were conscious; they just thought they were). Any other definition of consciousness must comprise some element of a non-material explanation for it (I note that Pixy remarks in this thread that his proof works regardless of whether materialism is true, but I'm not so sure; I think it depends on what we mean by "by definition"--I take it to be under any materialist definition).
Remember that Win was the biggest proponent of the p-zombie argument here, and its most dogged defender. Win presented it numerous times, with considerable patience, in an effort to demonstrate that qualia and experience cannot be accounted for by a materialistic explanation for consciousness. He did so as a "student" (admirer, as I do not believe Win actually studied under Chalmers himself) of Chalmers.
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This is not directed as you, Ian, but did anyone else think it was some sort of inside philosophy joke that a new poster named "Mary Dennett" entered this discussion? The reason I ask is because Daniel Dennett (author of
Consciousness Explained and very much a materialist, and TAM4 speaker) is a well-known and respected philosopher and probably the most vocal opponent of David Chalmers and Chalmers' p-zombie argument. I thought it was hilarious that perhaps someone masquerading as his wife or daughter or other close relative might jump in here. Apparently, it's merely a coincidence.
AS
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