Hedonic treadmill

The hedonic treadmill, also known as hedonic adaptation, is the observed tendency of humans to quickly return to a relatively stable level of happiness despite major positive or negative events or life changes. According to this theory, as a person makes more money, expectations and desires rise in tandem, which results in no permanent gain in happiness. Brickman and Campbell coined the term in their essay "Hedonic Relativism and Planning the Good Society" (1971). During the late 1990s, the concept was modified by Michael Eysenck, a British psychologist, to become the current "hedonic treadmill theory" which compares the pursuit of happiness to a person on a treadmill, who has to keep walking just to stay in the same place. The concept dates back centuries, to such writers as St. Augustine, cited in Robert Burton's 1621 Anatomy of Melancholy: "A true saying it is, Desire hath no rest, is infinite in itself, endless, and as one calls it, a perpetual rack, or horse-mill."

The hedonic (or happiness) set point has gained interest throughout the field of positive psychology where it has been developed and revised further. Given that hedonic adaptation generally demonstrates that a person's long term happiness is not significantly affected by otherwise impactful events, positive psychology has concerned itself with the discovery of things that can lead to lasting changes in happiness levels.

Hedonic adaptation is a process or mechanism that reduces the affective impact of emotional events. Generally, hedonic adaptation involves a happiness "set point", whereby humans generally maintain a constant level of happiness throughout their lives, despite events that occur in their environment. The process of hedonic adaptation is often conceptualized as a treadmill, since one must continually work to maintain a certain level of happiness. Others conceptualize hedonic adaptation as functioning similarly to a thermostat (a negative feedback system) that works to maintain an individual's happiness set point. One of the main concerns of positive psychology is determining how to maintain or raise one's happiness set point, and further, what kind of practices lead to lasting happiness.

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