 We are concerned here with moral reasoning as a species of practical reasoning – reasoning directed to deciding what to do and, if successful, issuing in an intention. But how can such practical reasoning succeed? How can moral reasoning hook up with motivationally effective psychological states so as to have this kind of causal effect? “Moral psychology” – the traditional name for the philosophical study of intention and action – has a lot to say to such questions, both in its traditional, a priori form and its newly popular empirical form. In addition, the conclusions of moral psychology can have substantive moral implications, for it may be reasonable to assume that if there are deep reasons that a given type of moral reasoning cannot be practical, then any principles that demand such reasoning are unsound. In this spirit, Samuel Scheffler has explored “the importance for moral philosophy of some tolerably realistic understanding of human motivational psychology” (Scheffler 1992, 8) and Peter Railton has developed the idea that certain moral principles might generate a kind of “alienation” (Railton 1984). In short, we may be interested in what makes practical reasoning of a certain sort psychologically possible both for its own sake and as a way of working out some of the content of moral theory. 