Thomas Nagel Quote
I believe that there is a necessary connection in both directions between the physical and the mental, but that it cannot be discovered a priori. Opinion is strongly divided on the credibility of some kind of functionalist reductionism, and I won't go through my reasons for being on the antireductionist side of that debate. Despite significant attempts by a number of philosophers to describe the functional manifestations of conscious mental states, I continue to believe that no purely functionalist characterization of a system entails — simply in virtue of our mental concepts — that the system is conscious.
"Conceiving the Impossible and the Mind-Body Problem," Royal Institute of Philosophy annual lecture, given in London on February 18, 1998, published in Philosophy vol. 73 no. 285, July 1998, pp 337-352, Cambridge University Press, p. 337.