FOR the evolutionarily minded, the existence of fairness is a puzzle. What biological advantage accrues to those who behave in a trusting and co-operative way with unrelated individuals? And when those encounters are one-off events with strangers it is even harder to explain why humans do not choose to behave selfishly. The standard answer is that people are born with an innate social psychology that is calibrated to the lives of their ancestors in the small-scale societies of the Palaeolithic. Fairness, in other words, is an evolutionary hangover from a time when most human relationships were with relatives with whom one shared a genetic interest and who it was generally, therefore, pointless to cheat.
The problem with this idea is that the concept of fairness varies a lot, depending on which society it happens to come from—something that does not sit well with the idea that it is an evolved psychological tool. Another suggestion, then, is that fairness is a social construct that emerged recently in response to cultural changes such as the development of trade. It may also, some suggest, be bound up with the rise of organised religion.
Joseph Henrich at the University of British Columbia and his colleagues wanted to test these conflicting hypotheses. They reasoned that if notions of fairness are, indeed, calibrated to the Palaeolithic, then any variation from place to place should be random. If such notions are cultural artefacts, though, they will vary systematically with some aspect of society. In a study just published in Science, Dr Henrich and his team looked at the relationship between notions of fairness and two social phenomena: the degree to which a society is economically integrated and how religious the individuals within it are.
To do the study Dr Henrich recruited 2,148 volunteers from 15 contemporary, small-scale societies. The societies in question included the Dolgan (hunters in Siberia), the Hadza (foraging nomads in Tanzania) and the Sanquianga (fishermen in Colombia).
First, the volunteers were asked to play a series of games that would measure their notions of fairness. One of these is called the dictator game. In it, two players (who do not actually meet) are given a sum of money. One of them then divides the money and gives whatever fraction he chooses to the other. Not much of a game, perhaps, but it provides a good measure of the first player’s sense of fairness, since he has the power to be as unfair as he likes.
Another game the researchers asked participants to play was more subtle. In it, the second player has the opportunity to reject the sum offered by the first, in which case neither player receives anything. In this version, however, the second player must decide what offer he would accept (within a 10% margin of error), and do so before he hears what the offer actually is. That provides a measure of willingness to punish, even at a cost to the punisher. Yet another game looked at interactions with third parties.
Having established prevailing notions of fairness in each of the societies they were examining, the researchers then calculated a measure of that society’s market integration. They arrived at this by working out the percentage of a household’s total calories that were purchased from the market, as opposed to being grown, hunted or fished. The volunteers were also asked whether they participated in a world religion (rather than a tribal one).
The results back a cultural explanation of fairness—or, at least, of the variable levels of fairness found in different societies. In fact, those societies that most resemble the anthropological consensus of what Palaeolithic life would have been like (hunting and gathering, with only a modicum of trade) were the ones where fairness seemed to count least. People living in communities that lack market integration display relatively little concern with fairness or with punishing unfairness in transactions. Notions of fairness increase steadily as societies achieve greater market integration (see chart). People from better-integrated societies are also more likely to punish those who do not play fair, even when this is costly to themselves.
For progressives, this finding brings great comfort. It suggests that people are, if not perfectible, at least morally malleable in positive ways. If economic integration is the driving force for fairness then it may make sense to view it as something like a type of technology. As societies have become more complex, those that have developed systems of sanitation, transport, energy and so on have been more successful than those which have not. It may be that the notion of fair play is an intangible equivalent of these systems.
Dr Henrich also, however, found that the sense of fairness in a society was linked to the degree of its participation in a world religion. Participation in such religion led to offers in the dictator game that were up to 10 percentage points higher than those of non-participants.
World religions such as Christianity, with their moral codes, their omniscient, judgmental gods and their beliefs in heaven and hell, might indeed be expected to enforce notions of fairness on their participants, so this observation makes sense. From an economic point of view, therefore, such judgmental religions are actually a progressive force. That might explain why many societies that have embraced them have been so successful, and thus why such beliefs become world religions in the first place.