Psychological egoism

Psychological egoism is the view that humans are always motivated by self-interest, even in what seem to be acts of altruism. It claims that, when people choose to help others, they do so ultimately because of the personal benefits that they themselves expect to obtain, directly or indirectly, from doing so. This is a descriptive rather than normative view, since it only makes claims about how things are, not how they ought to be. It is, however, related to several other normative forms of egoism, such as ethical egoism and rational egoism.

A specific form of psychological egoism is psychological hedonism, the view that the ultimate motive for all voluntary human action is the desire to experience pleasure or to avoid pain. Many discussions of psychological egoism focus on this type, but the two are not the same: theorists have explained behavior motivated by self-interest without using pleasure and pain as the final causes of behavior. Psychological hedonism argues actions are caused by both a need for pleasure immediately and in the future. However, immediate gratification can be sacrificed for a chance of greater, future pleasure. Further, humans are not motivated to strictly avoid pain and only pursue pleasure, but, instead, humans will endure pain to achieve the greatest net pleasure. Accordingly, all actions are tools for increasing pleasure or decreasing pain, even those defined as altruistic and those that do not cause an immediate change in satisfaction levels.

Beginning with ancient philosophy, Epicureanism claims humans live to maximize pleasure.Epicurus argued the theory of human behavior being motivated by pleasure alone is evidenced from infancy to adulthood. Humanity performs altruistic, honorable, and virtuous acts not for the sake of another or because of a moral code but rather to increase the well being of the self.

In modern philosophy, Jeremy Bentham asserted, like Epicurus, that human behavior is governed by a need to increase pleasure and decrease pain. Bentham explicitly described what types and qualities of pain and pleasure exist, and how human motives are singularly explained using psychological hedonism. Bentham attempted to quantify psychological hedonism. Bentham endeavored to find the ideal human behavior based on hedonic calculus or the measurement of relative gains and losses in pain and pleasure to determine the most pleasurable action a human could choose in a situation.

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