USING MORAL PRINCIPLES TO GUIDE DECISIONS

A long line of moral philosophers have argued that one, or the principal, role of a moral theory is to provide guidance to agents in deciding what to do. Given this, they have rejected as inadequate moral theories that cannot be used for guidance, however attractive they may be as theoretical accounts of what makes acts right or wrong. Thus, in a classic statement, James Hudson rejects objective utilitarianism, which prescribes maximizing utility, on the grounds that " for human agents the theory is not really " action-guiding " : it does say what one should do, but it gives this information in a practically unusable way, " 1 because no one can be confident which action would maximize utility over the very long run. Utilitarianism is notoriously subject to problems of applicability because of agents' difficulty in ascertaining which action would maximize utility. However, deontological theories are subject to similar limitations on agents' knowledge. An agent may be uncertain or mistaken about, or unable to ascertain, whether the statement he is considering making is untrue and so a For a selection of other examples of philosophers who require moral theories to be usable for guidance, see H. A. Prichard, " Duty and Ignorance of Fact, " in H.