Robert Wright
Our deepest emotions, from romantic love to moral outrage, are shaped in part by strategies natural selection favored for passing on genes.
Men and women evolved divergent reproductive strategies based on differing biological investments, with males generally seeking mating quantity and females prioritizing partners offering resources and commitment.
Altruism toward family members is a genetic strategy known as kin selection, driving us to make sacrifices in part according to how much DNA we share.
Friendships and social alliances operate on a system of reciprocal altruism, where feelings of pity and gratitude function as unconscious accounting mechanisms that help sustain mutually beneficial exchanges.