Most people in most of the world are nice. But most societies - including most alleged democracies - are ruled by nasty leaders. An inescapable, empirical fact, it accounts for almost all the trouble in the world - imperialism, the two world wars, the unspeakable regime of Saddam Hussein, and the unspeakable response to it by the minority government that now controls the United States and hence the rest of the world. Democracy ought to mean rule by the people. It seems to follow that, if only democracy could truly be made to work, then the world ought to be a nice and peaceful place, because nice people, given a choice, will surely opt for peace.
So why doesn't democracy work? Why has it almost never worked, except (so anthropologists tell us) in some ancient tribes, which have now been largely eliminated? Why - even in the modern societies that call themselves democratic and hold themselves up as models for the rest to follow - are nice people almost invariably led by nasty people, who screw things up?
The answer, I suggest, is provided by game theory: the notion that was formulated first by the Hungarian-American mathematician John Von Neumann in the 1930s. It describes in mathematical terms what happens when two or more individuals (or societies) interact, and so it predicts which life strategies or "games" are likely to prevail in different situations. Economists and the military were the first to seize on game theory, but in the late 20th century, the great English biologist John Maynard Smith applied it to problems of evolution. This was one of several refinements that hugely improved on Charles Darwin's initial insights of the mid-19th century, when he described the basic mechanism of natural selection. Darwinian natural selection (refined by game theory) predicts that most human beings are bound to be nice. But game theory on its own shows why the nice will lose out to the nasty unless they gird their loins, smarten up their act, put trust in their own niceness and that of others, and boot the nasties into touch. If the nice (most of us) do those things, then the future, despite all signs to the contrary, could still be rosy.
Most people will be surprised to learn that natural selection predicts innate niceness. They have heard that natural selection is rooted in competition; and in a crowded world, competition is to the death. Richard Dawkins understands evolutionary theory better than most, but even he emphasises that nature is "ruthless". Well before Darwin, theorists of all kinds took it to be self-evident that the strong are bound to bash the weak, and many post- Darwinians felt that natural selection merely ratified what had always been undeniable. But Darwin himself, gentle Whig that he was, never felt this; and he took pains to point out (although he found it puzzling) that animals are sociable. Co-operation is a winning formula - otherwise, it would not be such a common feature of nature. Also, as a good moralist, Darwin never assumed (as some post-Darwinians all too readily did) that what happens in nature is necessarily right. Nature can be vicious, but natural viciousness doesn't excuse unpleasantness in people.
A short chain of reasoning takes us from the broad observation that some animals are social to the prediction that most human beings are likely to be nice. Some animals are so social that they divide up the tasks of living between them, to the point where no individual can survive alone. Such creatures are said to be "eusocial", "eu" being Greek for "good" (as in "good and proper"). Ants and bees are like this, as are some mammals, such as mole rats and meerkats. Humans are eusocial, too. Robinson Crusoe would have perished on his island had he not rescued bits and pieces from the shipwreck - things made by other human beings.
Social creatures of all kinds have a whole "suite" of behavioural codes that enable them to get along with their fellow creatures, and such codes might reasonably be called "manners". In eusocial creatures, such behaviour is developed in spades. With ants and bees, it seems entirely innate: the individuals simply respond reflexively to the smells and touch of their companions. Modern psychology (and common observation) shows that most human behaviour is innate, too. We don't think consciously about walking or driving a car - if we do, we instantly become incompetent. Neither do we think consciously about the rudiments of sociality. As with ants, bees and meerkats, the rudiments of good manners are instinctive in us, although they still need to be brought out and refined by learning.
Manners alone, however, do not imply niceness. It seems absurd to suggest that an ant is "nice". What makes the difference in humans is that we think and that we have choice. We could decide to be nasty, while an ant is "hard-wired" to follow the code of its species and has no such option. Furthermore, human beings (like some other clever, social animals such as lions and gorillas) have developed a "theory of mind". We do not simply judge what another individual wants of us from their odour, or from the particular stroke of an antenna. Each of us assumes that everyone else, like ourselves, has a mind of his or her own, with thoughts and moods. In adjusting our behaviour to others we try to anticipate how they will react. Sociality implies that we try, in general, to evoke a favourable response from the people around us. Common sense says that we will get the best response if we keep our fellows happy; and a (partly) conscious attempt to keep our fellows happy is at least the raw material of niceness.
Game theory suggests, too, that it is worth making some personal sacrifice to keep others happy, if only to ensure that they respond favourably towards us - or at least not unfavourably. That may be seen simply as enlightened self-interest: another step towards niceness, but not quite the finished article. The final refinement is to develop a positive desire to keep others happy. With that, we can truly claim to be nice.
Common sense (and observation) suggests that we are more likely to do things if we have a positive desire to do them. So the whole argument suggests that, in so far as natural selection influences behaviour at all (which it undeniably does), then in eusocial, thinking, emotional creatures such as us, it ought to favour not only behaviour that keeps others happy, but also a desire to do so. This is not mere wishful thinking. It is the logical and almost inescapable conclusion from modern evolutionary theory, rooted in Darwin's ideas but with 140 years' refinement.
This is where game theory queers the pitch. Two notions are particularly pertinent: the idea of hawks and doves; and that of the freeloader.
The hawk and dove idea (which Maynard Smith in parti- cular has discussed) begins with natural selection in its tradi-tional, Tennysonian guise of nature, red in tooth and claw. It acknowledges that survival, followed by production of progeny, is the most basic game. It acknowledges, too, that if everyone behaves peaceably and nicely and co-operatively - like doves, at least in their mythological form - then the way is open for individuals who behave hawkishly. The doves toil, and make a pleasant society in a pleasant world; but then the hawks swagger in and take what the doves have created. The doves, being doves, do not fight back. An all-dove society is in many ways splendid. No individual is hurt or treated unjustly; and because the society wastes no time and energy in fighting, and in recovering from fights, what Jeremy Bentham called "the greatest happiness of the greatest number" is maximised. But, said Maynard Smith, the all-dove society is not robust. It is always liable to be invaded, not to say infected, by hawks. The hawks do not need to "invade" from outside. They arise from within - either by some genetic mutation that produces an aggressive variant, or (in creatures such as ourselves, with flexible behaviour and the ability to choose) because an individual opts to bash his or her fellows rather than play fair.
Game theory also predicts, however, that the hawks will not wax fat for ever. For a time, they will do well - and so they will multiply. Indeed, they will do so well for a time that society will soon be overrun with hawks. Then, when the hawks try to swagger in and pinch whatever they want, they find themselves confronted not by compliant doves, but by other hawks: a bloody fight ensues, in which one of the hawks is very definitely the loser. All this is inevitable, said Maynard Smith. The "evolutionarily stable state" - the state of affairs that will come about if natural selection simply runs its course - is a society with a majority of doves, but a minority of hawks. But the dovish majority will always be ruled by the hawkish minority.
Doves are recognisably nice. Hawks may be affable, with the trappings of sociality (Stalin comes readily to mind), but what really matters is their hawkishness, and hawkishness can be very nasty indeed. In hawks, natural selection does not specifically favour niceness. Thus, nice people are bound to be ruled by nasty people. Nice rulers (such as Mahatma Gandhi, Nelson Mandela or Vaclav Havel) arise in societies that are dominated by superhawks (the British, the whites, the Soviet Union). In such cases, game theory predicts that dovishness is the only tactic liable to make any headway at all. But when the superhawks finally depart and normal service is resumed, the formerly oppressed society almost invariably acquires a conventionally hawkish leader.
Freeloaders are always liable to arise because both dovishness and hawkishness, in their pristine forms and in their different ways, are hard work. Better neither to toil unselfishly nor to spend one's days battling for supremacy. Easier by far simply to sit on the sidelines and pick up the spoils. Hence the petty thief, the conman, the shirker and the cheat. Hawks and doves alike despise cheats and freeloaders, and have keen social whiskers to detect them. Yet cheating is always a possibility, so all creatures, including human beings, tend to mistrust each other. For hawks, such innate suspicion is helpful. It is part of their hawkishness. It gives them an excuse to cut down their fellows pre-emptively. For doves, mistrust is weakening. It reduces their will to co-operate - by being generous, they simply open themselves up to exploitation. Clever hawks reinforce their own position by fostering the mistrust that lurks in the most dovish bosom. Divide and rule: Machiavelli described the tactic 500 years ago.
So what's the solution? For my part, I am a naive soul, educated as a child in a Church of England primary school in south London. I have never been a paid-up Christian (I find the mythology hard), but have boundless admiration for Christ. He advocated an all-dove society. When Peter said (I'm paraphrasing, but not much): "If you behave like a dove, you get bashed", Jesus replied: "Yes, but it's worth it. The prize of an all-dove society is so great that it is worth suffering some inconvenience in order to bring it about. In any case, people bash you, for the most part, not because they want to behave like hawks, but because they don't trust you. They are getting their retaliation in first. If you show you will not retaliate, they will realise that their mistrust is inappropriate, and stop being aggressive."
Analysed in terms of game theory, Jesus was being subtle, and absolutely accurate. Gandhi said much the same. I am citing Christianity (though probably best spelt with a small c) simply because I was brought up with it. Properly interpreted (as Gandhi said), any of the great religions expresses the same kind of notion. Islam is about peace, too.
I also recall a quaint idea called socialism. Socialism has taken many forms, some of which (like some versions of Christianity and every other religion, including Islam) have been extremely unpleasant: hawkishness in disguise. But socialism shouldn't be seen as any particular structure. It needn't, for example, imply the centralised economy. It needn't mean Clause Four. At root, it simply implies a particular attitude to society. As individuals, we all have to live, and we owe it to ourselves to look after ourselves. (Indeed, Catholics would argue that we do not belong to ourselves, and owe it to God to look after ourselves.) But as eusocial creatures, we need other people as well. Even if we were mindless and amoral, like ants, we would need to behave in ways that left our fellow creatures reasonably intact. Even hawks have to exercise some restraint, or they destroy the individuals they prey upon. But truly to cement society, to make it strong and worth belonging to, we should think beyond immediate, enlightened self-interest. We should think positively in terms of making a society that coheres, and is as dovish as possible. For that, we should be prepared to make significant self-sacrifice, as Christ, Gandhi and many other prophets have been arguing for a very long time. We need to think of our own well-being, but we should split our allegiance, unconsciously and as a matter of policy, and consider at the same time the well-being of society as a whole. This is the root of socialism.
Socialist politics is a way (or a multiplicity of ways) of enacting that notion through policy. Because of hawks, freeloaders, mistrust and short-term inconvenience, it is difficult. But it's worth it. Just because the Soviet Union turned sour, and in the end failed, and the world has gone off on a tack that's quite different, and new Labour has won power by disowning socialism, it does not mean that the world as a whole should give up on it. It is one of the most valuable and necessary ideas we have.
Democracy is very difficult, too - partly for inescapable reasons of game theory (hawks bash doves), but also for logistic reasons (how can people's disparate and somewhat labile desires be turned into coherent action?). But we can't afford to give up on that either. The good news to emerge from modern biology is that, if democracy could be made to work at all, then it ought to produce excellent results - precisely because, deep down, despite all appearances, and in contrast to the claims of rulers who want to justify their rule and of economists who think that people merely aspire to grow rich, human beings are creatures that have evolved to be nice. That is an encouraging start.
Colin Tudge's latest book, So Shall We Reap, on the state of world agriculture, will be published by Penguin in September