In this chapter I discuss Kant's view of cognition against the historical background. In particular, I stress a historical approach to Kant in depicting the critical philosophy as reacting to and correcting the Platonic position. In the Critique of Pure Reason, Kant suggests it is possible to know a philosopher's position better than its author in pointing to Plato. Kant is then depicted as following Plato's rejection of a backward cognitive inference from appearance to reality in further denying intellectual intuition. Kant's solution lies in the Copernican solution that we know only what we in some sense can be said to construct. The effort to formulate an acceptable version of this insight is central to Kant's critical philosophy as well as to post-Kantian German idealism.