I propose to explain Kant’s novel claim, in the Critique of Pure Reason, that all judgments have a formal modality. I begin by distinguishing the modality of a judgment’s form from the modality of its content, and I suggest that the former is peculiar in merely affecting the subject’s understanding of his own act of judging. I then contrast the modal account of such an understanding (in terms of the possibility and actuality of a judgment) with the traditional, non-modal understanding (...) of it (in terms of the giving and withholding of assent). I conclude by suggesting that Kant prefers the former because he conceives of knowledge on Aristotle’s model: as a progress in the mind from capacity to act. (shrink)

Kant presents three principles of modality in the Critique of Pure Reason. Historically, commentators have mostly disregarded them; a few have rejected them outright. In recent years, however, a consensus has begun to develop around the idea that the role of these principles is to rule out certain metaphysical doctrines. I argue that this understates their importance. Rather, the principles of modality are essential conditions of the possibility of experience. I conclude by examining the question of their truth, which, I (...) argue, can only be grasped by considering them as postulates—i.e., as practical propositions of a certain kind. (shrink)