Varieties of Happiness critically examines the widespread belief that Greek ethics is a distinctive type of ethical theory labeled "eudaimonist." Plainly, if a theory is eudaimonist, then the notion of eudaimonia must play a crucial role. Iakovos Vasiliou argues, however, that although it is true that ancient philosophers discuss eudaimonia frequently, it is far less clear that it plays a role in their ethical theories such that it makes for a distinctive kind of theory. Merely discussing what makes a human life a happy one is insufficient for a theory to be eudaimonist. Any philosopher might have views about what a happy life is, without that making their mode of ethical reasoning and deliberation distinctly eudaimonist.

Vasiliou identifies and critically analyzes three roles eudaimonia may play, which, individually or jointly, have been thought sufficient to make a theory eudaimonist: (1) as a comprehensive practical principle; (2) as a concept that can provide the content for virtuous action; and (3) as a motivation to pursue virtue. Through detailed interpretations of texts on happiness and virtue from Plato's Socratic dialogues, The Republic and Symposium, Aristotle's Nicomachean Ethics, Epicurus, and the early Stoics, this book invites us to revise our understanding of ancient ethics.