Why Functionalism Is a Form of ‘Token-Dualism’

We present a novel reductive theory of type-identity physicalism (called Flat Physicalism), which is inspired by the foundations of statistical mechanics as a general theory of natural kinds. We show that all the claims mounted against type-identity physicalism in the literature don’t apply to Flat Physicalism, and moreover that this reductive theory solves many of the problems faced by the various non-reductive approaches including functionalism. In particular, we show that Flat Physicalism can account for the (alleged) appearance of multiple realizability in the special sciences, and that it gives a novel account of the genuine autonomy of the kinds and laws in the special sciences. We further show that the thesis of genuine multiple realization, which is compatible with all forms of non-reductive approaches including functionalism, implies what we call token-dualism; namely the idea that in every token (that partakes in this multiple realization) there are non-physical facts, which may either be non-physical properties or some non-physical substance; that is, we prove that non-reductive kinds necessarily assume non-reductive tokens, i.e., token-dualism. We then consider a surprising feature of our approach, in which, despite its fully reductive nature, the special sciences are still genuinely autonomous, after all. Finally, we show that all forms of non-reductive approaches including functionalism imply a literally multi-leveled structure of reality.