John Phillips

Some types of mental states, such as beliefs and intentions, can be rational or irrational. Others, such as itches and visual perceptions, are not properly assessed in these terms; they are simply nonrational. Where is the boundary between the rationally evaluable and the nonrational to be found, and how is it determined? What makes it the case that some parts of people’s mental lives are be subject to this special sort of evaluation? This dissertation offers an account of rationality and of rational evaluation designed to answer these questions. This project argues that rational evaluation is a special case of the skill evaluation applicable to human endeavors generally. It develops that claim by considering how a mental state, as opposed to an action, can constitute an endeavor, and seeks to account for differences between rationality and forms of skill displayed in other domains.