Comparisons with Homonymous Predicates in Aristotle

Aristotle claims that cross-sense comparisons—that is, comparisons with respect to homonymous predicates—are impossible. At the same time, he uses such comparisons in arguments that are fundamental to his philosophical project, such as when he claims that happiness is better than instrumental goods. In this paper, I discuss how this tension arises, and I explain why the cross-sense comparisons Aristotle uses are nevertheless possible. Using evidence from the Protrepticus , I claim Aristotle distinguishes two kinds of comparisons: comparisons of degrees of a quality, and comparisons of the priority with which a quality applies. Only the latter admits of some cross-sense comparisons.