Perfectionism, the view that well-being is a matter of developing characteristically human capacities, has relatively few defenders in the literature, but plenty of critics. This paper defends perfectionism against some recent formulations of classic objections, namely, the objection that perfectionism ignores the relevance of pleasure or preference for well-being, and a sophisticated version of the ‘wrong properties’ objection, according to which the intuitive plausibility of the perfectionist ideal is threatened by an absence of theoretical pressure to accept putative wrong properties (...) cases. The paper argues these objections are unsuccessful, but introduce a new worry, the Deep Problem: Perfectionism fails to offer a satisfying foundational justification for why developing the human essence is valuable. The paper responds to the deep problem, ultimately arguing that it is a puzzle put to all theories of well-being to provide a justification for their normative significance. (shrink)