In Nicomachean Ethics X.5, Aristotle gives a series of arguments for the claim that pleasures differ from one another in kind in accordance with the differences in kind among the activities they arise in connection with. I develop an interpretation of these arguments based on an interpretation of his theory of pleasure (which I have defended elsewhere) according to which pleasure is the perfection of perfect activity. In the course of developing this interpretation, I reconstruct Aristotle’s phenomenology of pleasure, arguing (...) that while he denies that all pleasures share any given phenomenal element, he does think that all pleasures have a common phenomenal structure. Finally, I argue that Aristotle’s view that pleasures differ in kind does not imply that they cannot be compared in pleasantness. (shrink)