The human capacity to exert self-control is arguably one of the most
powerful and beneficial adaptations of the human psyche. People are
happiest and healthiest when there is an optimal fit between self and
environment, and this fit can be substantially improved by altering
the self to fit the world (Rothbaum, Weisz, & Snyder, 1982). Indeed,
the self’s capacity to inhibit its antisocial impulses and conform to
the demands of group life has been proposed to be the hallmark of
civilized life (Freud, 1930). Even today, the vast majority of social
and personal problems seem on theoretical grounds to involve a
substantial component of deficient self-control