From self-deprivation to cooperation: How Ramadan fasting influences risk-aversion and decisions in resource dilemmas

Abstract

Across the world, many cultural and religious groups participate in collective deprivation rituals such as the Ramadan fast. It is not obvious why people willingly deny themselves sustenance for prolonged periods of time. Apart from the physical hardship, fasting may have psychological and behavioral consequences comparable to those associated with involuntary scarcity and poverty, including susceptibility to impaired cognitive performance or increased risk-aversion and delay discounting. In this paper I propose and investigate one explanation for communal fasting rituals, that it is associated with increased cooperation over common resources, in part, through increased risk-aversion. I test the two prongs of this hypothesis in a series of studies. Studies 1a–c investigate the relation between the Ramadan fast and risk-taking, finding lower risk-taking in fasters than non-fasters and during Ramadan than after. In a repeated measures design, Study 2 (N = 283) finds that in multiparty resource dilemmas, people make smaller requests from commons with unknown size during Ramadan than after, and this difference is associated with corresponding shifts in risk-taking, but not indices of trust or social preferences. I propose that collective deprivation rituals may have served an adaptive sociocultural function in times of scarcity when incomplete information about the availability of resources and other people's response could increase defection and threaten commons with rapid depletion. Along with implications for research into the psychology of fasting, rituals, and cooperation in resource dilemmas under uncertainty, these results demonstrate Ramadan's potential as a natural laboratory for cognitive and behavioral research.