Abstract

Paul Draper has recently developed an account of intrinsic probability according to which a theory's intrinsic probability is determined by its modesty and coherence. He employs this account in an argument that Source Physicalism (SP) and Source Idealism (SI) are equally intrinsically probable. Since SP and SI are not exhaustive, and Theism is one very specific version of SI, it follows that the intrinsic probability of Theism is very low. I argue here that considerations of fundamentality show that more work needs to be done to defend the claim that P(SP) = P(SI).