Defending the Refutation of Idealism

Abstract

In his Kant and the Claims of Knowledge, Paul Guyer offers an influential reading of Kant’s famous “Refutation of Idealism.” Guyer’s reading has been widely praised as Kantian exegesis but less favorably received as an anti-skeptical line of argument worthy of contemporary interest. In this paper, I focus on defending the general thrust of Guyer’s reading as a response to Cartesian skepticism. The paper falls into two sections. The first section constructs Guyer’s central argument in three steps and gives it a quasi-formal presentation. That presentation reveals the principal obstacle to the argument’s being convincing to a contemporary audience, namely, its apparent reliance on Kant’s prohibition against psychological laws governing mental states. The second section constructs a lemma in defense of Guyer’s general line of attack. In effect, it suggests that that line does not depend on a metaphysical ban on psychological laws, but only on the modest premise that according to the Cartesian’s concept of knowledge such laws cannot justify claims about the temporal order of the self.