Theories of Practical Reason

Abstract

Leading theories of practical reason can be grouped into one of four families: psychologism, realism, compatibilism, and Aristotelianism. Although there are many differences among the theories within each family, I ignore these in order to ask which family is most likely to deliver a satisfactory philosophical account of reasons for action. I articulate three requirements we should expect any adequate theory of practical reason to meet: it should account for (1) how reasons explain action, (2) how reasons justify action, and (3) how an agent can act for the reason that justifies her action. Only the Aristotelian theory, however, can meet all three requirements. It avoids the problems that plague the other theories by grounding reasons neither in psychological states nor in facts totally independent of the agent in question, but in the nature of the kind of creature the agent is. Our explanations of action need descend to the biographical only when explaining why a human being does not act in ways characteristic of her kind. The Aristotelian view of practical reason, then, appears to be the most promising program for future work.