The distinction between approach and avoidance motivation has a long history in scientific psychology, as well as in intellectual thought more generally. The approach-avoidance distinction first appeared in the writings of the ancient Greek philosophers Democritus (460-370 B.C.E.) and Aristippus (435-356 B.C.E.), who advocated an ethical hedonism in which the pursuit of pleasure and the avoidance of pain were proscribed as the optimal guide for human behavior. Many years later the British philosopher Jeremy Bentham (1748-1832) articulated a psychological hedonism in which the pursuit of pleasure and the avoidance of pain were viewed descriptively (rather than prescriptively) as the way in which human beings actually behave. William James (1890/1950) identified pleasure and pain as “springs of action,” describing them as strong reinforcers and inhibitors of behavior, respectively, and offered speculation regarding the neural mechanisms underlying approach and avoidance tendencies. Many of the most prominent contributors to psychological theory since the time of James have explicitly incorporated approach-avoidance concepts and principles into their work; this is true across theoretical and metatheoretical perspectives and across substantive domains of inquiry (see Elliot, 1999, for a review).