Reciprocal altruism involves foregoing an immediate benefit for the sake of a greater long-term reward. It follows that individuals who exhibit a stronger preference for future over immediate rewards should be more disposed to engage in reciprocal altruism – in other words, ‘patient’ people should be more cooperative. The present study tested this prediction by investigating whether participants’ contributions in a public-good game correlated with their ‘discount rate’. The hypothesis was supported: patient people are indeed more cooperative. The paper discusses (...) alternative interpretations of this result, and makes some suggestions for future research. (shrink)

The adaptationist framework is necessary and sufficient for unifying the social and natural sciences. Gintis's “beliefs, preferences, and constraints” (BPC) model compares unfavorably to this framework because it lacks criteria for determining special design, incorrectly assumes that standard evolutionary theory predicts individual rationality maximisation, does not adequately recognize the impact of psychological mechanisms on culture, and is mute on the behavioural implications of intragenomic conflict. (Published Online April 27 2007).