Ernest Sosa

This chapter has four parts. The first lays out Williamson's account of mental concepts and mental states, and his characterization of knowledge as the most general factive stative attitude. The second problematizes the account of mental states and the characterization of knowledge, and offers an alternative account of when a state is purely mental; according to this account, knowledge really is mental only by courtesy of the contained belief (an internalist intuition opposed to the externalism featured in the book). The third part reflects on possible sources and support for such a conception of the purely mental. The fourth and last part takes up the KK principle, Williamson's reductio of it, and the consequences of that for the possibility of reflective knowledge.

Ernest Sosa extends his distinctive approach to epistemology, intertwining issues concerning the role of the will in judgment and belief with issues of epistemic evaluation. Questions about skepticism and the nature of knowledge are at the forefront. The answers defended are new in their explicit and sustained focus on judgment and epistemic agency. While noting that human knowledge trades on distinctive psychological capacities, Sosa also emphasizes the role of the social in human knowledge. Basic animal knowledge is supplemented by a level of reflective knowledge focused on judgment, and a level of 'knowing full well' that is distinctive of the animal that is rational.