Abstract

The epistemic argument against physicalism supports the claim that if physicalism is true, then none of our beliefs are rationally justified. The argument relies on two major premises. The first places a constraint on rationally justified belief, according to which S's believing that p is rationally justified only if there is some reason for p, r, which S believes and S's believing that r is part of a true causal explanation for S's believing that p. The second advances the conceptual claim that if physicalism is true, then no reason r can be part of a true explanation for S's believing that p. ;This dissertation constitutes an effort to clarify and to defend the two major premises of the epistemic argument against physicalism, with a special emphasis on the second premise. I begin with a critical appraisal of work by William Hasker and Norman Malcolm, who offer arguments similar to mine. In doing so, I offer a set of thought experiments to motivate my proposed constraint on rationally justified belief. Subsequently, I consider two physicalist models of mental causation, a nonreductive token identity theory and a reductive functionalism, as instances of how the proposed constraint might be met, given physicalism. I argue that the former fails for reasons of causal-explanatory exclusion, and that the latter "succeeds" at the expense of mental realism, a consequence I take to count decisively against such a model. I conclude by considering the ramifications for the physicalist if the conditional conclusion the main argument is established