externalism the view that there are objective reasons for action that are not dependent on the agent’s desires, and in that sense external to the agent. Internalism (about reasons) is the view that reasons for action must be internal in the sense that they are grounded in motivational facts about the agent, e.g. her desires and goals. Classic internalists such as Hume deny that there are objective reasons for action. For instance, whether the fact that an action would promote health is a reason to do it depends on whether one has a desire to be healthy. It may be a reason for some and not for others. The doctrine is hence a version of relativism; a fact is a reason only insofar as it is so connected to an agent’s psychological states that it can motivate the agent. By contrast, externalists hold that not all reasons depend on the internal states of particular agents. Thus an externalist could hold that promoting health is objectively good and that the fact that an action would promote one’s health is a reason to perform it regardless of whether one desires health. This dispute is closely tied to the debate over motivational internalism, which may be conceived as the view that moral beliefs (for instance) are, by virtue of entailing motivation, internal reasons for action. Those who reject motivational internalism must either deny that (sound) moral beliefs always provide reasons for action or hold that they provide external reasons. See also ETHICS , MOTIVATIONAL INTERNAL – ISM , RELATIVIS. W.T.