An argument against motivational internalism

I argue that motivational internalism should not be driving metaethics. I first show that many arguments for motivational internalism beg the question by resting on an illicit appeal to internalist assumptions about the nature of reasons. Then I make a distinction between weak internalism and the weakest form of internalism. Weak internalism allows that agents fail to act according to their normative judgments when they are practically irrational. I show that when we clarify the notion of practical irrationality it does not support motivational internalism. Weakest internalism only claims that agents are irrational if they entirely lack motivation to do what they judge they ought to. I do not argue against weakest internalism, but I argue that it is not an important view.