Kant repeatedly claims his critical enterprise is analogous to pure general logic (PGL) in embodying the self-knowledge of reason. I argue that PGL is self-knowledge in the sense that its claims are epistemically grounded in pure apperception, which yields insight into the form of thinking in general. Kant’s critical epistemology, as distinct from his critical metaphysics, is self-knowledge in an analogous sense: It is an apperceptively grounded inquiry into the form of all a priori thought about objects. I develop an account of the purity, generality, and formality of PGL, which I then leverage into an outline of the apperceptive method that underwrites Kant’s faculty psychology. This novel account of Kant’s critical method distinguishes it from the analytical but dogmatic method of Wolff and the reflective but empirical methods of Locke and Tetens.