Abstract

This paper offers a simple and novel motivation for the Humean Theory of Reasons. According to the Humean Theory of Reasons, all reasons must be explained by some psychological state of the agent for whom they are reasons, such as a desire. This view is commonly thought¹ to be motivated by a substantive theory about the power of reasons to motivate known as reason internalism, and a substantive theory about the possibility of being motivated without a desire known as the Humean Theory of Motivation. Such a motivation would place substantial constraints on what form the Humean Theory of Reasons might take, and incur substantial commitments in metaethics and moral psychology. The argument offered here, on the other hand, is based entirely on relatively uncontroversial methodological considerations of perfectly broad applicability, and on the commonplace observation that while some reasons are reasons for anyone, others are reasons for only some. The argument is a highly defeasible one, but is supposed to give us a direct insight into what is philosophically deep about the puzzles raised for ethical theory by the Humean Theory of Reasons. I claim that it should renew our interest in the relationship between these two kinds of reason, and in particular in the explanation of reasons which seem to depend on desires or other psychological states