In the Groundwork Kant dismisses theistic principles, along with all other competitors to his Categorical Imperative, claiming that they are heteronomous. By contrast, he asserts, the fundamental moral principle must be a principle of autonomy. I argue that the best case for this Kantian conclusion conflates our access to the reasons for our commitments with an ability to state these reasons such that they could figure in an argument. This conflation, in turn, results from a certain Kantian conception of inclination, (...) and its role in our moral psychology. These are views that we ought to reject. Having done so we will see that a theistic ethics based on desire or love for God would not face a distinctive problem of heteronomy. (shrink)