 The most basic aim of moral philosophy, and so also of the Groundwork, is, in Kant’s view, to “seek out” the foundational principle of a “metaphysics of morals,” which Kant understands as a system of a priori moral principles that apply the CI to human persons in all times and cultures. Kant pursues this project through the first two chapters of the Groundwork. He proceeds by analyzing and elucidating commonsense ideas about morality, including the ideas of a “good will” and “duty”. The point of this first project is to come up with a precise statement of the principle or principles on which all of our ordinary moral judgments are based. The judgments in question are supposed to be those that any normal, sane, adult human being would accept on due rational reflection. Nowadays, however, many would regard Kant as being overly optimistic about the depth and extent of moral agreement. Perhaps he is best thought of as drawing on a moral viewpoint that is very widely shared and which contains some general judgments that are very deeply held. In any case, he does not appear to take himself to be primarily addressing a genuine moral skeptic such as those who often populate the works of moral philosophers, that is, someone who doubts that she has any reason to act morally and whose moral behavior hinges on a rational proof that philosophers might try to give. For instance, when, in the third and final chapter of the Groundwork, Kant takes up his second fundamental aim, to “establish” this foundational moral principle as a demand of each person’s own rational will, his conclusion apparently falls short of answering those who want a proof that we really are bound by moral requirements. He rests this second project on the position that we — or at least creatures with rational wills — possess autonomy. The argument of this second project does often appear to try to reach out to a metaphysical fact about our wills. This has led some readers to the conclusion that he is, after all, trying to justify moral requirements by appealing to a fact — our autonomy — that even a moral skeptic would have to recognize.