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.
David PapineauI 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.
David PapineauI don't think that we can figure out what is going on in conscious colour perception just by phenomenological introspection. We need to know about brain mechanisms as well. We need to figure out what information is present in the mechanisms that constitute conscious colour perception.
David PapineauA century ago mainstream science was still quite happy to countenance vital and mental powers which had a 'downwards' causal influence on the physical realm in a straightforwardly interactionist way. It was only in the middle of the last century that science finally concluded that there are no such non-physical forces. At which point a whole pile of smart philosophers (Feigl, Smart, Putnam, Davidson, Lewis) quickly pointed out that mental, biological and social phenomena must themselves be physical, in order to produce the physical effects that they do.
David PapineauKripke says that physicalists like me can't explain the 'apparent contingency' of mind-brain identities. He maintains that, if I really believed that pains are C-fibres, then I ought no longer to have any room for the thought that 'they' might come apart. His argument is that, since pains aren't identified via some contingent description, but in terms of how they feel, I have no good way of constructing a possible world, so to speak, where C-fibres are present yet pains absent.
David PapineauNearly 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.
David PapineauMy first degree was in mathematics. That was great, but it didn't help with many of the things that puzzled me. I became a philosopher because I wanted to understand everything, especially those things that didn't make sense. And that has continued to be my philosophical motivation. That's one reason I have such a roving philosophical eye - once I have figured out a philosophical topic to my satisfaction, I find myself moving on to new problems.
David Papineau