According to the intuitionist picture of moral normativity, prima facie duties are features of the overall nature of an act, which together make them overall right or wrong. W.D. Ross says that prima facie duties are «not a duty», but something which has a special relation to duty. These fea-tures are «apprehended» by way of an intellectual act (intuition), which implies that they are the object of a theoretical cognitive act. This image creates serious problems for both the theory of moral normativity and the theory of motivation. The problem is how to explain the practical nature of duties and their connection with the will: the intuitionist picture sketches a rather passive role for the will, both in determining the obligatoriness of an ...