ABSTRACT
Scientific and ordinary understanding of human social behaviour assumes that the Humean theory of motivation is true. The Humean theory of motivation is committed to two claims. Desires and beliefs are ‘distinct existences’ – they are distinct mental states, where the existence of one does not imply the existence of the other. And being motivated to act is never merely a matter of having certain beliefs, but also always requires having some desire. In Hume’s words: “reason alone can never be a motive to any action of the will. . . . Reason is, and ought only to be, the slave of the passions, and can never pretend to any other office than to serve and obey them” (Hume 1978, 413, 415).
