In his critical works of the 1780's, Kant claims, seemingly inconsistently, that (1) theoretical and practical reason are one and the same reason, applied differently, (2) that he still needs to show that they are, and (3) that theoretical and practical reason are united. I first argue that current interpretations of Kant's doctrine of the unity of reason are insufficient. But rather than concluding that Kant’s doctrine becomes coherent only in the Critique of Judgment, I show that the three statements (...) are compatible, providing a new and more coherent account of Kant's 1780's doctrine of the unity of reason. (shrink)