In an age of increasing inequality and social divide there is often a lot of speculation about what we mean by fairness and justice. A fascinating new study by Patricia Kanngiesser from the University of Bristol and Prof Felix Warneken from Harvard University has shown how fairness seems to be something of an innate human trait.. This is one of a swathe of studies looking at fairness, altruism and cooperation in children in recent years. In their new study children of about 3 years old were asked to collect coins using a fishing rod alongside a puppet partner. The researchers cleverly varied the work-contribution of both partners by manipulating how many coins each partner collected. The coins could then be exchanged for rewards. Interestingly the children kept fewer stickers for themselves when they had contributed little effort than when they had contributed the most, showing that they took fairness into account.
This study has come hot on the heels of other recent studies by Renee Baillargeon and David Premack  which was even more extraordinary. In these tests babies have a couple of animated giraffes placed in front of them and the giraffes are larking around. Then along comes someone with toys, and the giraffes show pleasure. When the toys are shared equally, say three each, the babies do not react at all, seemingly because they expect fairness. However if one giraffe was to get more than the other, say five of the six, the babies stare for longer and they can look perturbed. It seems that they have an innate expectation of what is just and have an idea that ‘this is not fair’. Another experiment also has 2 versions. 21 month olds watch two women clear up some toys and are rewarded for this task. Some babies though see only one of the women doing her share of clearing up while the other continued to merrily play away. In these scenarios, if both women were rewarded equally then the babies stared for longer, communicating that ‘this is not what is meant to happen’. Yet another study showed that, when presented with a simple story, 3-year-olds thought that a character who finished baking deserved more cookies than a character who got bored and stopped early.
Research using game theory has shown this with adults for some time now. Typical is the Ultimatum Game, and a new study just published reiterated what other studies have long shown. In the classic ultimatum games, someone is given a pot of money and they have to make an offer of a proportion of it to someone else. If the person accepts the offer, then they both keep these amounts. If the respondent refuses then neither gets anything. In studies in just about every culture people feel insulted by low offers and refuse, even if this means getting nothing themselves/. In the majority of cultures acceptable offers are somewhere between 30 and 50%. A recent British study found something similar. In this study , half were given a salt solution to make them thirsty and others a placebo. They were all presented with two glasses of water with a highly unequal offer that they were told was from the Proposer: The glass offered to them contained only an eighth of the original bottle of water, and the other contained the remaining seven eighths that the Proposer wanted to keep for themselves. They had fifteen seconds to decide whether to accept or reject the offer and in fact tended to reject the highly unequal offer, even if they were severely thirsty. Once again this shows how strong a motivating force fairness is.
The evolutionary roots of such egalitarian traits in our hunter gatherer past has been demonstrated recently by evolutionary thinkers such as Boehm  and E.O. Wilson . Other great apes such as chimps do not respond in this kind of way.; for example chimpanzees in Ultimatum Games accept any offer, acting more as the self-interested maximisers expected of homo economicus.. While there is a lot of research about altruistic and cooperative tendencies, the research about fairness, and the desire to punish unfairness, raises other questions about human morality. Jonathon Haidt  has recently developed a new theory about morality in his book, the Righteous Mind, in which he argues that people politically on the left and on the right might have very different ideas about what constitutes morality and fairness. Those on the left tend to value fairness in terms of a care ethic, such as looking after the weak and needy, and believing more in equality. Those on the right get much more indignant about people not pulling their weight and argue that people need to ‘deserve’ their rewards. It is such sentiments that fuel the maybe surprising support for neoliberal right-wing tea-party supporters' sentiments, and these people argue as much for their version of fairness as do those on the left. Haidt has argued that people on the liberal left simply do not understand the morality of those on the right, which includes not only more belief in fairness as proportional to effort, but also a belief in values such as loyalty and betrayal and respecting traditional authority, values that most on the left would think of as alien and incomprehensible. He argues that the left have often lost and not been understand by many potential voters by not taking these differences this into account.
 P. Kanngiesser and F. Warneken, ‘Young Children Consider Merit when Sharing Resources with Others’, PLoS ONE, vol. 7, no. 8, p. e43979, Aug. 2012.
 S. Sloane, R. Baillargeon, and D. Premack, ‘Do infants have a sense of fairness?’, Psychological Science, vol. 23, no. 2, pp. 196–204, 2012.
 N. Baumard, O. Mascaro, and C. Chevallier, ‘Preschoolers are able to take merit into account when distributing goods.’, Developmental Psychology, vol. 48, no. 2, p. 492, 2012.
 R. H. Thaler, ‘Anomalies: The ultimatum game’, The Journal of Economic Perspectives, vol. 2, no. 4, pp. 195–206, 1988.
 N. D. Wright, K. Hodgson, S. M. Fleming, M. Symmonds, M. Guitart-Masip, and R. J. Dolan, ‘Human responses to unfairness with primary rewards and their biological limits’, Scientific Reports, vol. 2, Aug. 2012.
 C. Boehm, Moral Origins: The Evolution of Virtue, Altruism, and Shame. Basic Books, 2012.
 E. O. Wilson, The Social Conquest of Earth. W. W. Norton & Co., 2012.
 J. Haidt, The Righteous Mind: Why Good People are Divided by Politics and Religion. London: Allen Lane, 2012.