The chapter explores in the nature of the act of the will Kant analyses in Groundwork I and II. I argue that Kant provides us with a metaphysical – and not phenomenological – analysis of what it means to have a will. The phenomenological analysis is subject to skeptical challenges. His argument is based on what follows when we take ourselves as having a will, something that we do every time we act. This analysis reveals that the act of willing immediately implies a subjection to the moral law. This act of the will is identical to the fact of reason with which Kant begins his second Critique. I show this through a closer look at what follows when we take the will as negatively free, that is, as not determined in the order of causes. I argue that Kant held that when we examine the essence of the will, it follows that any act of willing that is negatively free must also have a law of its activity, one supplied by reason, for the idea of an undetermined will contains a contradiction (6:35). Hence any act of the will must embody both negative and positive freedom. This means further that Kant is an internalist about reasons for moral action.

This chapter demonstrates that a correct understanding of Kant’s argument for the bindingness of the moral law in Groundwork III succeeds. Through his critique of the conditions of the possibility of the act of willing, Kant demonstrates that any act of the will involves our activity as intelligences. This includes action in accordance with hypothetical imperatives, which involves the capacity to understand what is required in order for us to influence the world and so act in it; it requires the capacity to act in accordance with laws. Kant characterizes his argument in Groundwork III as a deduction answering the question: With what right we are bound by the categorical imperative? It proceeds in three essential steps: an analysis of (1) negative freedom and the logical conditions of judgment in all practical principles; (2) moral valuation and the problem of the circle, and (3) positive freedom as implied in the act of reflection as the self understands itself as acting in accordance with the idea of laws. When we so act, we transfer ourselves into the world of intelligences and must assume the conditions of membership in such a world. These include being bound by the moral law.