Right. But that’s a guide to action, not a description of the good (which utilitarianism purports to be). The utilitarian would justify that course of action with reference to its leading to higher expected utility. If the empirical facts about humanity were such that it is more efficient for us to calculate expected utility for every action individually, then those folks would not advocate following rules, while “rule utilitarians” still would.
Right. But that’s a guide to action, not a description of the good (which utilitarianism purports to be). The utilitarian would justify that course of action with reference to its leading to higher expected utility. If the empirical facts about humanity were such that it is more efficient for us to calculate expected utility for every action individually, then those folks would not advocate following rules, while “rule utilitarians” still would.