Abstrakt
In suggesting that new nations often coalesce in the decades following war, historians have posed an important psychological question: does the experience of war generate an enduring elevation in people's egalitarian motivations toward their in-group? We administered social choice tasks to over a thousand children and adults differentially affected by wars in the Republic of Georgia and Sierra Leone. We find that greater exposure to war creates a lasting increase in egalitarian motivations towards one's in-group, but not out-groups, during a developmental window that starts in middle childhood (~7 years) and ends in early adulthood (~20 years).
Outside this window, war has no measurable impacts on social motivations in young children, and only muted effects on older adults. While "war effects" are broadly consistent with predictions from evolutionary approaches that emphasize the importance of group cooperation against external threats, they also highlight key areas in need of greater theoretical development.