This chapter spells out in detail how Kant's thinking about logic during the critical period shapes the account of philosophy that he gives in the Critiques. Tolley explores Kant's motivations behind his formation of the idea of a new "transcendental" logic, drawing out in particular how he means to differentiate it from the traditional "merely formal" approaches to logic, insofar as transcendental logic investigates not just the basic forms of the activity of thinking but also its basic contents. Kant's understanding of both of these logics directly factor into the first Critique's more general project of the critique of reason in particular, as not just a capacity for a certain kind of thinking (inferring), but as a possible source of a priori cognition.