I consider an underappreciated problem for proponents of the Humean theory of motivation. Namely, it is unclear whether is it to be understood as a largely psychological or largely metaphysical theory. I show that the psychological interpretation of HTM will need to be modified in order to be a tenable view and, as it will turn out, the modifications required render it virtually philosophically empty. I then argue that the largely metaphysical interpretation is the only a plausible interpretation of HTM's (...) central claim that desires are necessary conditions for motivation. This interpretation also fits better with the important roles that HTM plays in both moral psychological and metaethical debates. (shrink)

I argue against motivational internalism. First I recharacterise the issue over moral motivation. Second I describe the indifference argument against motivation internalism. Third I consider appeals to irrationality that are often made in the face of this argument, and I show that they are ineffective. Lastly, I draw the motivational externalist conclusion and reflect on the nature of the issue.