Epistemological Physicalism and the Knowledge Argument

This paper offers a new solution to the knowledge argument. Both a priori and a posteriori physicalists reject the claim that Mary does not know all the facts, but they do so for different reasons. While the former think that Mary gains no new knowledge of any fact, the latter think that Mary gains new knowledge of an old fact. This paper argues that on a broad understanding of what counts as physical, it is consistent with physicalism that Mary does not know all the physical facts, and that on a narrow understanding, it is consistent with physicalism that Mary knows all the physical facts, but not all the facts. Either way, Mary gains new knowledge of a new fact that is not non-physical. The resultant view—epistemological physicalism—has it that although one cannot know everything just by knowing complete physical theory, everything is metaphysically necessitated by what one can know just by knowing such theory. Finally, some objections that have been raised against this view are presented and replies are considered. I. The Varieties of Physicalism Physicalism is often held to be the view that everything is entirely physical: there are no facts or properties that are not physical facts or properties. In particular, if physicalism is actually true, phenomenal properties are all purely physical properties.