There is a philosophical view about morality which is shared by moral philosophers as divergent as Kant, Kierkegaard, Nietzsche, Royce, Hare, Popper, Sartre, and Wolff. It is a view of the moral agent as necessarily autonomous. It is this view that I wish to understand and evaluate in this essay. I speak of a view and not a thesis because the position involves not merely a conception of autonomy but connected views about the nature of moral principles, of moral epistemology, of rationality, and of responsibility.