This paper seeks to assess the claim of Aristotelian naturalism to successfully vindicate the virtues. To this end, I consider two ways to understand the claims of Aristotelian naturalism and, thus, the normative authority of nature. The first is represented by an interpretation of Aristotelian naturalism as defending the claim that practical rationality is species-relative. I argue that the view fails because it cannot accommodate certain forms of moral disagreement. As an alternative, I propose seeing Aristotelian naturalism as the expression (...) of a particular ethical outlook, which is based on identifying as a living organism in the order of nature. Since this identification is neither universal nor necessary, my view suggests that Aristotelian naturalism is more parochial than its proponents believe, but it is not, for that reason, invalidated. As an articulation of the fundamental principles of a particular ethical outlook, Aristotelian naturalism can provide a limited form of vindication for certain virtues. I conclude with remarks on the prospects for naturalist vindication beyond an ethical outlook. (shrink)