ABSTRACT
The idea is that rational deliberators decide what to do by taking account of their beliefs and desires. This common-sense idea has been made precise by the science called decision theory; rational agents are said to “maximize expected utility.” Psychological egoism maintains that concern for others is purely instrumental, never ultimate. There is a point of agreement between William James and this defender of psychological egoism. Although they disagree over which effect of the helping behavior is the goal and which is the mere side effect, they agree that there is a difference between the two. The difference between Pure Egoists and S-over-O Pluralists, on the one hand, and O-over-S Pluralists and Pure Altruists, on the other, shows up when there is a conflict between helping one’s self and having others be better-off. Evolutionary biologists discuss “altruism” and “selfishness,” but they aren’t talking about psychological motives when they use these terms.
