In this book Julian Wuerth offers a radically new interpretation of Kants theories of mind, action, and ethics. As the author of a Copernican revolution in philosophy, Kant grounded his philosophy in his positive theory of the mind, which remains an enigma two centuries later. Wuerths original interpretation of Kants theory of mind consults a far wider range of Kants recorded thought than previous interpretations, revealing a fascinating evolution in Kants thought in the decades before and after his 1781 Critique. Starting in the 1760s, Kant recognized the unique status of our epistemic contact to ourselves. This is the sole instance of our immediate epistemic contact with a substance, of being a substance, and it is the sole instance of epistemic contact with something other than the particular states of inner sense. Contrary to empiricists, Kant thus rejects the reduction of the self to a bundle of mental states of inner sense. But Kant also rejects the rational psychologists assumption that the souls substantiality and simplicity implies its permanence, incorruptibility, and immortality.As Kant developed his transcendental idealism, he eventually pinpointed the source of their errors, a source neither unique to a particular, historical school, nor random. It is instead a deep, natural, and timeless transcendental confusion. Kants new account of substance allows him to draw new distinctions in kind between sensibility and understanding and between phenomenal and noumenal substance, setting the stage for a transcendental argument that only at the phenomenal level do substantiality and simplicity imply permanence and incorruptibility. Wuerth next undertakes a groundbreaking study of Kants theory of action and ethics. He first maps Kants notoriously vast and complex system of the minds powers, drawing on all of Kants recorded thought. This system structures Kants philosophy as a whole and so provides crucial insights into this whole and its parts, includin