If there is such a simple argument for physicalism, how come everybody hasn't always been a physicalist? That's a good question, and there is a good answer. The 'causal completeness of physics' wasn't widely accepted until recently.

I realize that I won't have quite enough time to understand everything - but that hasn't stopped me wanting to understand as much as I can.

This doesn't show that there is anything wrong with our theoretical understanding, any more than the intuition that the Earth is at rest shows that there must be something theoretically wrong with Copernicanism, or the intuition that time is moving shows that there is something theoretically wrong with the block universe 'B series' view of change.

Of course our genes will make some capacities very much easier to learn than others, and of course our genes themselves are not learned. But the point remains that genes themselves are not cognitive capacities, and that anything worth calling a cognitive capacity will depend to some degree on learning and so not be innate.

I think my view is rather more radical than Pete Mandik's. Both of us want to show that colour perception doesn't transcend what can be conceptualized, but I don't think he goes so far as to deny that it doesn't involve different responses to all the discriminable surfaces.

Nearly everybody nowadays accepts the 'causal completeness of physics' - every physical event (or at least its probability) has a full physical cause. This leaves no room for non-physical things to make a causal difference to physical effects. But it would be absurd to deny that thoughts and feelings (and population movements and economic depressions . . .) cause physical effects. So they must be physical things.

I say that there is nothing deficient about our current theoretical grasp of mind-brain identities. The problem is only that they are counter-intuitive.