THE SOURCE OF NORMATIVITY AND THE PARADOXES OF SELF-LEGISLATION

In the Preface to the Grundlegung, Kant announces that he will pursue two main objectives, respectively, to “seek out” and then to “establish” the “supreme principle of morality.” The first objective is achieved in the first two sections of the book, in what is an essentially descriptive enterprise. Kant shows there that morally good actions are those actions done from duty, regardless of one’s inclinations, and proceeds to derive from this idea of acting from duty a supreme moral principle, on the basis of which the moral agent can determine with what particular duty he is expected to comply in particular circumstances – the categorical imperative. In the book’s third section, Kant then turns to the normative question, which arises out of the skeptical worry that morality might be little more than “a phantom of the brain,” or that those moral obligations we take to be objective and unconditional are in fact not rational requirements at all, but mere fantasies.

In a few transitional pages at the end of the second section, Kant develops a view that forms a crucial preliminary to the argument of the final section. Before he can attempt to establish the normative authority of the supreme principle of morality he described previously, he must specify where that authority must be sought in the first place – that is to say, he must formulate a view about the source of normativity. Suppose we are told that we should help the needy, and we want to know whether this is a legitimate requirement. To go about answering that question, we must first figure out what to look for – or what will count as a justification of this claim.