Steven Pinker in Edge:

PinkerHuman beings live in groups, are affected by the fortunes of their groups, and sometimes make sacrifices that benefit their groups. Does this mean that the human brain has been shaped by natural selection to promote the welfare of the group in competition with other groups, even when it damages the welfare of the person and his or her kin? If so, does the theory of natural selection have to be revamped to designate “groups” as units of selection, analogous to the role played in the theory by genes? Several scientists whom I greatly respect have said so in prominent places. And they have gone on to use the theory of group selection to make eye-opening claims about the human condition.[i] They have claimed that human morailty, particularly our willingness to engage in acts of altruism, can be explained as an adaptation to group-against-group competition. As E. O. Wilson explains, “In a group, selfish individuals beat altruistic individuals. But, groups of altruistic individuals beat groups of selfish individuals.” They have proposed that group selection can explain the mystery of religion, because a shared belief in supernatural beings can foster group cohesion. They suggest that evolution has equipped humans to solve tragedies of the commons (also known as collective action dilemmas and public goods games), in which actions that benefit the individual may harm the community; familiar examples include overfishing, highway congestion, tax evasion, and carbon emissions. And they have drawn normative moral and political conclusions from these scientific beliefs, such as that we should recognize the wisdom behind conservative values, like religiosity, patriotism, and puritanism, and that we should valorize a communitarian loyalty and sacrifice for the good of the group over an every-man-for-himself individualism.

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