 Addressing the moral skeptic, after all, is the project Plato undertook in the Republic: in Book I he rehearses an argument to show that justice is not really a virtue, and the remainder of this work is an attempt to rebut this thesis. Aristotle’s project seems, at least on the surface, to be quite different. He does not appear to be addressing someone who has genuine doubts about the value of justice or kindred qualities. Perhaps, then, he realizes how little can be accomplished, in the study of ethics, to provide it with a rational foundation. Perhaps he thinks that no reason can be given for being just, generous, and courageous. These are qualities one learns to love when one is a child, and having been properly habituated, one no longer looks for or needs a reason to exercise them. One can show, as a general point, that happiness consists in exercising some skills or other, but that the moral skills of a virtuous person are what one needs is not a proposition that can be established on the basis of argument.