Moral laws, according to Kant, are a set of orders issued to man by a nonheavenly, nonearthly entity (which I shall discuss shortly), a set of unconditional commandments or “categorical imperatives”—to be sharply contrasted with mere “counsels of prudence.” The latter are rules advising one how best to achieve one’s own welfare; such rules have for Kant no moral significance. By contrast, a categorical imperative pronounces an action “as good in itself,” no matter what the result, and thus “commands absolutely and without any incentives. . . .”

Unconditional obedience to such imperatives, “the submission of my will to a law without the intervention of other influences on my mind,” is man’s noblest virtue, the “far more worthy purpose of [men’s] existence, . . . the supreme condition to which the private purposes of men must for the most part defer.”

The name for such obedience is duty. “[T]he necessity of my actions from pure respect for the practical [i.e., moral] law constitutes duty. To duty every other motive must give place. . . .”

Kant draws a fundamental distinction between actions motivated by incentive or desire, actions which a man personally wants to perform to attain some end—these he calls actions from “inclination”—and actions motivated by reverence for duty. The former, he holds, are by their nature devoid of moral worth, which belongs exclusively to the latter. It is not enough that a man do the right thing, that his acts be “in accord with” duty; the moral man must act from duty; he must do his duty simply because it is his duty.