Two generally recognized moral duties are to reciprocate benefits one has received from others and to compensate harms one has done to others. In this paper I want to show that it is not possible to give an adequate account of either duty – or at least one that corresponds to our actual practices – within a contractualist moral theory of the type developed by T. M. Scanlon (1982, 1998). This fact is interesting in its own right, as contractualism is (...) a leading contemporary contender among deontological moral theories, and the two duties I have mentioned are fairly standard ingredients of such theories. But it also serves to highlight a general problem with contractualism, at least in Scanlon’s version – namely its one-dimensional view of the keystone of any plausible deontological theory: the idea of respect for persons. (shrink)