A mutualistic approach to morality: The evolution of fairness by partner choice

Abstract

What makes humans moral beings? This question can be understood either as a proximate "how" question or as an ultimate "why" question. The "how" question is about the mental and social mechanisms that produce moral judgments and interactions, and has been investigated by psychologists and social scientists. The "why" question is about the fitness consequences that explain why humans have morality, and has been discussed by evolutionary biologists in the context of the evolution of cooperation. Our goal here is to contribute to a fruitful articulation of such proximate and ultimate explanations of human morality. We develop an approach to morality as an adaptation to an environment in which individuals were in competition to be chosen and recruited in mutually advantageous cooperative interactions. In this environment, the best strategy is to treat others with impartiality and to share the costs and benefits of cooperation equally. Those who offer less than others will be left out of cooperation; conversely, those who offer more will be exploited by their partners. In line with this mutualistic approach, the study of a range of economic games involving property rights, collective actions, mutual help and punishment shows that participants' distributions aim at sharing the costs and benefits of interactions in an impartial way. In particular, the distribution of resources is influenced by effort and talent, and the perception of each participant's rights on the resources to be distributed. Abstract: What makes humans moral beings? This question can be understood either as a proximate "how" question or as an ultimate "why" question. The "how" question is about the mental and social mechanisms that produce moral judgments and interactions, and has been investigated by psychologists and social scientists. The "why" question is about the fitness consequences that explain why humans have morality, and has been discussed by evolutionary biologists in the context of the evolution of cooperation. Our goal here is to contribute to a fruitful articulation of such proximate and ultimate explanations of human morality. We develop an approach to morality as an adaptation to an environment in which individuals were in competition to be chosen and recruited in mutually advantageous cooperative interactions. In this environment, the best strategy is to treat others with impartiality and to share the costs and benefits of cooperation equally. Those who offer less than others will be left out of cooperation; conversely, those who offer more will be exploited by their partners. In line with this mutualistic approach, the study of a range of economic games involving property rights, collective actions, mutual help and punishment shows that participants' distributions aim at sharing the costs and benefits of interactions in an impartial way. In particular, the distribution of resources is influenced by effort and talent, and the perception of each participant's rights on the resources to be distributed.

Young children, but not chimpanzees, are averse to disadvantageous and advantageous inequities

“…The strong social component of inequity aversion in humans is assumed to originate from an evolutionary mechanism regulating successful cooperative interactions (e.g., Baumard, André, & Sperber, 2013;Fehr & Schmidt, 1999;Tomasello, 2009). The important role of inequity aversion also characterizes modern society, of course, ranging from promoting equal pay for men and woman to making charitable contributions to the poor.…”

The nature and dynamics of world religions: a life-history approach

“…In principle, people could espouse the values of extended prosociality, restricted sexuality and delayed gratification without any concern for other people's actions. This may be explained as a consequence of a general principle in human moral cognition, following which people intuitively disapprove of others' behaviours when the latter inflict a cost upon their interests that is not compensated by corresponding benefits [37]. Now, individuals with a slow strategy have a lot at stake in trying to deter others from adopting a fast strategy.…”

Partner choice versus punishment in human Prisoner’s Dilemmas

“…But what does 'best' actually mean? In the context of cooperation, the best partners are those who are most 30 able and most willing to confer benefits on others [7][8][9]. In hunter-gatherer societies, for example, those who hunt successfully and are also willing to share the spoils with others form more profitable relationships than those who are successful but do not share [10].…”