There is still disagreement among researchers about the question of the intention, unity and coherence of Kant's philosophy. In view of the distance in time to Kant, this state of affairs is as surprising as it is unsatisfactory. It is therefore all the more pleasing that new movement has come into Kant research, particularly as a result of recent research work, but also through the rediscovery of older contributions, which gives hope that certain fundamental questions of Kantian philosophy can indeed be answered. This also applies to the question of the unity and structure of the three critiques to be discussed in this articles. At the centre of this is the thesis that the three critiques, taken together, answer or attempt to answer the basic concern of a comprehensive critique of pure reason, namely to establish reason as the ultimate and self-founding principle of all experience. In itself, each of the three critiques represents a necessary moment of a more comprehensive movement of justification, which the critique as a whole goes through three times. In each of these passages, it encounters aporias that can no longer be resolved from its respective standpoint, but which lead to a necessary consequential standpoint. The order of the critiques of reason follows the classical doctrine of transcendentalism. Thus, reason in the theoretical forms the principle of systematic unity, in the practical forms the principle of objective validity, i.e. of truth, and in the reflection on the universality of the one reason underlying both forms of reason, the principle of perfection. From there, the Critique of Pure Reason as a whole should return to its beginning, namely to the exposition of its presupposition. The fact that Kant himself did not complete his system should not be a cause for regret, but rather lead to philosophising with Kant rather than about him.