In philosophy and related disciplines, hedonism is a school of thought which holds that the only intrinsic good is pleasure. A hedonist is essentially someone whose highest and ultimate objective is to maximize net pleasure—that is, total pleasure minus its opposite, pain. From a hedonistic perspective, ethically correct actions are those that increase overall pleasure while actions that reduce pleasure or increase pain are morally wrong. Hedonism has existed as a school since ancient times—a fact partly evident in relics such as the Epic of Gilgamesh, one of the oldest surviving works of literature.
Although a number of criticisms have been raised against hedonism, one of the most important of these is that it is impossible to found a general code of morality on the grounds of net pleasure. The key problem here is that pleasure is subjectively defined in numerous ways, whereas pain may encompass almost any unpleasant sensation, experience, event, or state of affairs. As such, each individual has a unique definition of the quality and quantity of pleasure and pain that are associated with any given entity or action. Another major criticism of hedonism concerns its presumption that human action is or should be motivated solely by pleasure. Indeed, for much of human history, ethical codes have been premised on the assumption that at least some people engage in tremendous acts self-abnegation for motivations that have little to do with pleasure maximization.