Different situations demand more of one aspect of human nature or the other. We may be satisfied with relying on the self-interest of the butcher or baker, but who really wants a doctor who views his patients as a way to make as much money as possible? People want doctors who care about their health and intrinsically want patients to be well. We want doctors who use the other half of human nature. Many, if not most, doctors go into medicine so they can do just that.

In business, however, human motivation is thought of mainly in self-interested financial terms. Chief executives are supposed to be motivated by stock options to make as much money as possible for shareholders, because they will also make the most money possible for themselves. In almost every aspect of business, people identify simple, measurable goals and try to tie self-interest to them.

Often, however, it is not easy to find simple goals in complex situations, and sometimes simple goals can be attained in undesirable ways. It is also unrealistic to think that human motivation can be reduced to individual self-interest. In doing this, we neglect the part of human nature that is altruistic.