On the relevance of supervenience theses to physicalism

This paper is an investigation into the nature of physicalism as well as to the possibility of formulating physicalism as a supervenience thesis. First, I review the motivation for finding a supervenience thesis that characterizes physicalism. Second, I briefly survey the types of supervenience theses that have been proposed as necessary (or, in some cases, as necessary and sufficient) for physicalism. Third, I analyze the recent supervenience thesis proposed by Frank Jackson and expounded upon by Gene Witmer. Jackson claims the supervenience thesis is both necessary and sufficient for physicalism; Witmer has proposed a different interpretation of one of the Jackson’s key notions and has suggested an amended supervenience thesis that is, if not sufficient, at least necessary for physicalism. However, I will argue that neither Jackson’s nor Witmer’s supervenience theses as stated are necessary for physicalism.