I argue for a perfectionist reading of Mill's account of the good life, by using the failures of development recorded in his Autobiography as a way to understand his official account of happiness in Utilitarianism. This work offers both a new perspective on Mill's thought, and a distinctive account of the role of aesthetic and emotional capacities in the most choiceworthy human life. I consider the philosophical purposes of autobiography, Mill's disagreements with Bentham, and the nature of competent judges and the pleasure they take in higher culture. I conclude that Millian perfectionism is an attractive and underappreciated option for contemporary value theory.