I avoid political commentary on this website , but in the current climate (31st January, 2017) I believe that it is very important for as many of us as possible to look dispassionately at what is happening and  try to understand what is going on below the surface rhetoric. The tool for this is game theory, about which I have written a book Rock, Paper, Scissors: Game Theory in Everyday Life.In it, I emphasize the paradoxes that scientists have uncovered, and which arise from our efforts to act solely in what we perceive to be our own best, while other people are acting in their own (sometimes very different) interests.

Here is an extract from the chapter “Tit for Tat,” which has a rather frightening contemporary relevance, even though the examples are from a children’s book!

Tit for Tat

My social training as a child was shaped by two frightening characters from a Victorian children’s story. Their names were Mrs Doasyouwouldbedoneby and Mrs Bedonebyasyoudid, and they appeared in Charles Kingsley’s The Water Babies, which my parents had given to me for my seventh birthday. Their moralities were very different, but both were ultimately based on “tit-for-tat” – a payback strategy that comes into play when the participants are likely to meet repeatedly. Game theorists have found that such repeated interactions are an important key to finding cooperative solutions for the seven deadly dilemmas, because the threat of future retaliation can deter cheats, while people are more likely to cooperate with you in the future if you have cooperated with them in the past.

Mrs D and Mrs B epitomised these two approaches, the first offering the carrot of cooperation, the second the threat of retaliation. In “The Water Babies”, these two alarming ladies act as moral guides to a little chimney sweep called Tom, who has fallen into a river and been turned into a water baby. Mrs D alarmed me because she was uncomfortably like my mother, always pushing the Golden Rule “Do unto others as you would have them do unto you.” She would never punish Tom directly when he broke that rule, but was an adept at emotional blackmail, simply letting Tom know how much he had upset her by his latest infraction of the rules, and then leaving him to worry about his own badness. I still dream about her sometimes.

Mrs B alarmed me for a different reason. She was a strict disciplinarian who reminded me of my nanna, a ferocious old lady who sniffed out evil and punished it with all the zeal of an Old Testament prophet. Unfortunately, the evil that she usually sniffed out was mine.

She sniffed it out literally on one occasion, when I had borrowed my father’s pipe to try out in privacy behind a hedge. She chased me three times around the garden at a time when all I wanted was solitude and repose, and it was only by dint of furious effort that I was able to climb the fence that separated us from the Presbyterian Church next door, where I was flamboyantly sick in a bed of hydrangeas, while she hung over the fence saying “Wait till you get home.” When I eventually slunk back to the house she was there waiting, with father’s pipe refilled and a box of matches in her hand. She made me smoke it right through, hoping to cure me of the dreadful habit. I often wonder if I took up pipe-smoking later in life just to spite her distant memory.

Mrs D and Mrs B represent two extreme approaches to the problem of interacting repeatedly with others. Mrs D’s “Do as you would be done by” is the “ethic of reciprocity” (otherwise known as the Golden Rule), which has been advocated by philosophers from Socrates onwards as a basis for practical morality, and which is advocated by most of the world’s major religions. Jesus propounded it in the Sermon on the Mount when he said “Do unto others as you would have them do unto you.” The Prophet Muhammad, in his last sermon, admonished believers to “hurt no one so that no one may hurt you”. Confucius said in The Analects “Never impose on others what you would not choose for yourself.” The Dalai Lama put it in a different, thought-provoking, form when he said “If you want others to be happy, practise compassion. If you want to be happy, practise compassion.”

The ethic of reciprocity is a statement of morality in which many of us believe, regardless of whether we have religious faith or not. Many philosophers have advanced it. Pythagoras said “What you wish your neighbors to be to you, such be also to them”, while the German philosopher Immanuel Kant made an even stronger statement when he made it an example of the categorical imperative “Act only according to that maxim whereby you can at the same time will that it should become a universal law.” The “categorical imperative” was, according to Kant, an absolute, unconditional requirement that exerts its authority in all circumstances, and which is both required and justified as an end in itself.

The ethic of reciprocity provides a guideline for how we would wish to behave, regardless of how others respond. In Mrs D’s hands, it was also a guideline to practical strategies. “If you want someone to trust you” she was effectively saying to Tom “the best thing is to show that you trust them first. If you want someone to love you, your best approach is to show that you love them. If you want someone to cooperate with you, try cooperating with them.”

Mrs D’s strategy was based on an optimistic assessment of human nature, which was in line with Kingsley’s position as a social reformer and minister with a “muscular Christian” attitude to life. Mrs B took a much more sceptical view of human behaviour and human values. “Be done by as you did” was an approach based on fear. It was the wrathful “eye for an eye” approach of the Old Testament Jehovah, rather than the forgiving “turn the other cheek” approach of the New Testament Jesus. “You can’t really trust anyone” it said “so if you need cooperation, the best way to get it is to threaten punishment for those who don’t cooperate. If what you are after is obedience and getting others to conform to your rules, the best way to get that is the threat of punishment as well.”

Both of these approaches have evolved in nature as means of obtaining and maintaining co-operation in circumstances where there can be repeated interactions between individual animals. American brown-headed cowbirds, for example, use Mrs B’s retributive tactics in a protection racket. “Raise my chick, or your eggs get it” is their threatening message to the warblers that inhabit the swamps around the Cache river in Southern Illinois. When a warbler lays its eggs, a cowbird will come along to lay its own egg right alongside. If the warbler raises all the chicks, including that of the cowbird, all is fine. If the warbler rejects the cowbird’s egg, however, the cowbird will retaliate by returning to the nest to eat or destroy the eggs of the warbler.

Rats, in contrast, use Mrs D’s “Do unto others as you would have them do unto you” – and it works! When rats in a cage pull a lever that releases food for a rat in an adjacent cage, the rat in the adjacent cage becomes much more inclined to pull a lever in its cage so as to feed another rat. Rats, in other words, are swayed by the kindness of strangers to act with kindness themselves, and the whole population of caged rats eventually becomes more altruistic.

Game theorists call the evoked behaviour “reciprocal altruism”, and rats are not the only animals to use it. Vampire bats will feed blood to others that haven’t managed to find any during the night, and the bats who have been fed then remember and return the favour. Chimpanzees will offer to share meat with others even when they are not related, and will go out of their way to help an unfamiliar human who is struggling to reach a stick, just as a small toddler will do.

The strategies of Mrs B and Mrs D have both contributed to the evolution of cooperation in Nature, but which one should we choose for ourselves? Both of them involve an element of risk. If we use Mrs D’s Golden Rule, we run the risk that others will not join us in “reciprocal altruism” by doing unto us as we have done unto them. If we adopt Mrs B’s threat of punishment and retaliation, we risk an ongoing cycle of retaliation and counter-retaliation if the other party does not succumb to the threat.