Valuing different human lives.

Do people think of the value of all human lives as equivalent irrespective of age? Affirmations of the equal value of all human lives are culturally prominent, yet much evidence points to the fact that the young are often prioritized over the old in life-and-death decision-making contexts. Studies 1-3 aimed to reconcile this tension by showing that although individuals are seen as more equal with respect to negative rights not to be harmed or killed (though not completely equal), they are seen as less equal with respect to positive rights to be aided or saved. Age exerts a large and systematic impact on decisions about who to save and about whose death is more tragic, suggesting that individuals are seen as possessing differing amounts of contingent value. These initial studies also yielded the novel finding that, although children are prioritized over adults, older children are often prioritized over younger children. Study 4 replicated this finding with a think-aloud methodology; the study showed that the preference for older children appears to be driven by their having had more invested in their lives, their better developed social relations, and their greater understanding of death. Studies 5a-5c demonstrated the independent causal effects of each of these variables on judgments of life's value. Finally, in Studies 6 and 7, mediation methods were used to show that older children's more meaningful social relations primarily explain the greater value of older than of younger children. These findings have implications for bioethics and medical policy.