This chapter argues that if we have a unified, comprehensive account of rationality for both domains, we should have much of the theoretical material needed to understand the notion of a rational person. But the matter is complicated. There are tradeoffs; for instance, a high degree of theoretical rationality might counterbalance some degree of practical irrationality, and no rational person need exhibit rationality all of the time. Some irrational actions, and even isolated moments of a wider irrationality, are compatible with the overall rationality of a person. Indeed, if some things, such as certain emotions, may fail to be rational without being irrational, then it is entirely consistent with being a rational person that one cultivate certain non-rational elements in oneself and allow them to play a significant role in one's life.
Keywords: desire, belief, will, attitudes, emotions, voluntariness, autonomy