Positive psychology has significantly influenced studies in the fields of moral philosophy, psychology and education, and scholars in those fields have attempted to apply its ideas and methods to moral education. Among various theoretical frameworks, virtue ethics is most likely to connect positive psychology to moral educational studies because it pursues "eudaimonia" (flourishing). However, some virtue ethicists have been concerned about whether the current mainstream concept of positive psychology can apply directly to moral education because it focuses on subjective aspects of happiness, but not its objective and moral aspects. Thus, I will consider whether the concept of purpose, which was investigated recently by a group of psychologists and emphasizes both subjective and objective aspects of happiness, can address this issue. I will examine whether purpose is a moral virtue contributing to flourishing, consider if its nature is possibly a second-order virtue and whether it is distinguishable from other second-order virtues.