H. A. Prichard ascribed to Aristotle a form of closeted hedonism. Aristotle allegedly misunderstood his own task: while his avowed goal in Nicomachean Ethics is to give an account of the nature of happiness, his real goal must be to offer an account of the factors most efficiently generating happiness. The reason is that the nature of happiness is enjoyment, and this fact is supposed to have been recognised by Aristotle and his audience. While later writers judged Prichard's view obviously mistaken, I argue that the issue is more complex. In the process of reconstructing the logical skeleton of Prichard's argument I show that Aristotle may have had to endorse the identification of the subject's good with that subject's psychological satisfaction. But I also argue that, while making prior assumptions about the meaning of ‘eudaimonia’, Aristotle made no such assumptions about the nature of eudaimonia.