What this criticism amounts to is the complaint that we need to be able to make sense of cases in which there are moral reasons on both sides, for and against. But we cannot do this effectively if all moral reasons are specified in absolute principles. Morality cannot, therefore, be just a system of absolute principles. The only way in which we could continue to think of morality as governed by absolute principles is to suppose that there is only one such principle, so that there is no possibili