Analyzing our deeds, we may find out that the motives behind these acts are unknown even to ourselves. Do people pursue some particular aim or act on instinct to satisfy some of their needs? According to the philosophic theory of psychological egoism, any human act can be explained as such that contributes to one’s own interests in the first place. On the other hand, psychological altruism justifies our good deeds saying that people still have altruistic motives to act for the sake of others. Whichever approach is considered as a more realistic one, it is really difficult to estimate the extent of human selfishness purely with the experimental data.
Apparently, some part of egoism is inherent to all human beings; the instinct for survival surely induces us to act for our own good which is very natural. Nevertheless feeling secure in their well-being, some people cease benefiting themselves and start contributing to the others. On the other hand, we have individuals that cannot stop looking for a personal advantage in every opportunity. Therefore, these two personality types are motivated by totally different things.
Motivation is a complex phenomenon, and it is not necessarily related to the notion of egoism. Actions of one and the same person may contain a different amount of an egoistic drive which proves that they shall not be estimated exceptionally from this point. Altruistic individuals may act to benefit the others instinctively or they may consciously decide to act this way. Which is more, some actions are thoroughly considered in advance so that unconscious motivation is very unlikely to take place.