Abstract

This chapter explains how the knowledge argument works and describes various physicalist responses to the knowledge argument. Frank Jackson first presented the knowledge argument in his 1982 paper, “Epiphenomenal Qualia”. “Qualia” refers to phenomenal properties: properties such as those Mary is said to understand only after leaving the room. Not everyone shares Jackson's opinion that epiphenomenalism is the best option for knowledge argument proponents. And some argue that there are versions of physicalism that the knowledge argument does not rule out. The most widely discussed such view is physicalist Russellian monism. Russellian monism combines two ideas. First, basic physics tells us about spatiotemporal‐causal structure but is silent about what underlies that structure. Second, there are intrinsic properties that both underlie that structure and constitute consciousness. Physicalist Russellian monism adds that those intrinsic properties are physical, even though they are not described by physics.