Interdependence Drives the Evolution of Morality

Morality is the human psychology built for cooperation, and its key concept is interdependence: just as kin selection has a mathematics for how much to help genetic relatives, interdependence follows the same formula with interdependence substituted for genetic relatedness, so that to the degree I depend on you for mating, foraging, or other needs, it is in my long-term fitness interest to help you, share fairly, and treat you with respect—and computational cooperation models fail to capture this because they assume independent agents rather than interdependent social networks.