  Like ethical egoism, rational egoism needs arguments to support it. One might cite our most confident judgments about rational action and claim that rational egoism best fits these. The problem is that our most confident judgments about rational action seem to be captured by a different, extremely popular theory — the instrumental theory of rationality. According to the instrumental theory, I ought to perform some action if and only if, and because, performing that action maximizes the satisfaction of my preferences. Since psychological egoism seems false, it may be rational for me to make an uncompensated sacrifice for the sake of others, for this may be what, on balance, best satisfies my (strong, non-self-interested) preferences. This conflict with the instrumental theory is a major problem for rational egoism.