  The psychological egoist might reply that some such account must be right. After all, the soldier did what he most wanted to do, and so must have been pursuing his perceived self-interest. In one sense, this is true. If self-interest is identified with the satisfaction of all of one’s preferences, then all intentional action is self-interested (at least if intentional actions are always explained by citing preferences, as most believe). Psychological egoism turns out to be trivially true. This would not content defenders of psychological egoism, however. They intend an empirical theory that, like other such theories, it is at least possible to refute by observation.