There is a brain mechanism that works to identify colour differences directly, without first identifying the absolute colour of each surface. So on my view there is no reason to suppose anything like ten million colour responses to surface viewed singly.

If neuroscientific research shows that those mechanisms only contain comparative information about colour differences, and have 'thrown away' more fine-grained information about the absolute colours of single surfaces, then that would support my position, in a way that just introspecting our colour experiences can't.

A certain kind of methodologically-minded philosopher of science is quick to read off metaphysical conclusions from features of scientific practice. Chemists don't derive their laws from fundamental physics, so reductive physicalism must be false. Biologists refer to natural numbers in some of their explanations, so numbers must exist. I think that this kind of thing makes for bad philosophy.

The orthodox view of colour experience assumes that, when we see a colour difference between two surfaces viewed side-by-side, this is because we have different responses to each of the two surfaces viewed singly. Since we can detect colour differences between something like ten million different surfaces, this implies that we are capable of ten million colour responses to surfaces viewed singly.

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.

I don't have much use for the concept of innateness. The everyday concept incorporates a number of different notions that can come apart in in many ways, and as a result encourages a range of dangerously fallacious inferences.

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.