If the rational psychologist’s reasoning about the thinking subject were correct, we would have a metaphysical knowledge of the noumenal (e.g., of a simple substance), which would undercut Kant’s restriction of metaphysics to experience in the Critique. In the Paralogisms Kant doesn’t only negatively reject the psychologist’s reasoning, he also positively sets out what can be properly concluded about the thinking self. This positive conclusion is supposedly consistent with his own proscription against knowledge of the noumenal. It is noteworthy then that a recurrent criticism of Kant has been that his conception of the thinking self is not consistent with his doctrine of transcendental idealism, most especially the ideality of time.