In this paper I wish to put forward and defend a certain candidate for—I borrow the expression from Kant—the supreme principle of morality, understanding by ‘morality’ moral requirement or necessity.
It is a matter of fairly general agreement concerning judgments of moral requirement (which I shall call deontic judgments) (1) that singular judgments are generalizable, and (2) that all nonanalytic deontic judgments have prescriptive force. To amplify: An individual act, if it is judged to be morally required or morally wrong (its omission required), is judged to be such as falling under some completely general description, i.e. a description containing no uniquely referring expressions, and a general judgment respecting acts as acts of that description is implied. And it belongs to the very nature of non-analytic deontic judgments, i.e. it is true as a matter of meaning, that they bear on questions of rational decision or choice. The latter is true, of course, of all moral and other practical judgments. The case for the prescriptive force of affirmative deontic judgments can be put even more strongly, since they are understood not merely to provide, or affirm the existence of, reasons for choice, but to provide, or affirm the existence of overriding or imperative reasons, reasons which are therefore normally sufficient or conclusive, regardless of what the agent's wants may otherwise be.