Abstract
The paper argues for distinguishing two aspects in Kant’s idea of self-legislation of the moral law: the immediate character (i.e., the practical necessity) of the law itself and the lawgiving function attributed to the rational will. I argue that the novelty of Kant’s thesis chiefly consists in the combination of the two aspects, and that this solves the alleged paradoxical character of the idea of self-legislation. As it grounds on the connection of a fundamental law with a lawgiving, Kant’s view can be regarded as a novel variant of the mixed model first proposed by Suárez, with two crucial differences concerning the subject playing the role of the lawgiver and the notion of law involved. Finally, I argue that the inner structure of the idea of self-legislation shows that Kant’s view combines a realism of the moral law with a constructivism of moral obligation.