  All forms of egoism require explication of “self-interest” (or “welfare” or “well-being”). There are three main theories. Preference or desire accounts identify self-interest with the satisfaction of one’s desires. Often, and most plausibly, these desires are restricted to self-regarding desires. What makes a desire self-regarding is controversial, but there are clear cases and counter-cases: a desire for my own pleasure is self-regarding; a desire for the welfare of others is not. Objective accounts identify self-interest with the possession of states (such as virtue or knowledge) that are valuable independently of whether they are desired.  Hybrid accounts give a role to both desires (or pleasure) and states that are valuable independently of whether they are desired.  For example, perhaps the increase to my well-being brought about by a satisfied desire (or a pleasure) itself increases insofar as it is a desire for (or pleasure in) knowledge.  Or perhaps the increase to my well-being brought about by a piece of knowledge itself increases insofar as I desire (or take pleasure in) it.  Hedonism, which identifies self-interest with pleasure, is either a preference or an objective account, according to whether what counts as pleasure is determined by one’s desires. 