WE DON’T LIKE feral young men. When the Bluewater Shopping Centre in Kent banned the wearing of hoods, its number of visitors rose by more than 20 per cent. If the EU had put an anti-hoody clause into its proposed constitution, it might have won its referendums.

Young men are predators. As Tennyson asserted in The Princess, biology forces them into predation: “Man is the hunter; woman is his game.”

Charles Darwin explained why sex forces men into predation. To males, females are private goods. Once a male has consumed a female by making her pregnant, she is useless genetically to other males. Like a meal that has been consumed by someone else or a car that has been bought by someone else, she is spent. And, as economists remind us, people compete for private goods. It is because only one male can impregnate any particular female that males across the animal kingdom will fight over her.

Males, therefore, are instinctively aggressive, and they instinctively wear hoods to intimidate shoppers at Bluewater.

Yet to a female, males are public goods. No woman can monopolise a male’s sperm. John can bonk Sue in the morning but he has still got reserves for Jennie at lunchtime, Priscilla mid-afternoon and Suzanne for le cinq à sept before returning home to impregnate his wife in the evening. And because no female can monopolise a male — her tactic is to be coy and selective between courting males — she need not fight other women.

We are now so familiar with this theory that we forget that until recently it was heretical. In the 17th century John Locke, observing how societies differ from each other, proposed that man is born with a mind that is a tabula rasa. According to Locke, parents and teachers inscribe behaviour on children’s minds in the same way that teachers chalk on blank blackboards. If men are aggressive and women coy, then they have been taught to be so.

Until recently Locke’s views were standard among biologists. And they were right because different cultures do bring up children in very different ways. The result is that native Maori men, say, are transparently more aggressive than some Buddhist ones. Moreover, when children from one race are brought up by adults from another, they acquire the culture of their adopted society, not of their birth parents. Cultures — including male tendencies to violence — are indeed taught and learnt, and we know how.

Neuroscience research has shown that the brain’s areas of moral discretion, the frontal lobes, are not fully-formed until an individual is in his early twenties. We also know that those areas — and the moral values that they furnish — are moulded by early experiences, including those delivered by parents, teachers and peers.

But there are inherited sexual differences as well. In their book, Homicide, a survey of murder across 35 different societies, Martin Daly and Margo Wilson, the biologists, found that although murder rates varied hugely between cultures, the relative male propensity to kill did not. Men were on average 26 times more likely to kill than women. The message from anthropology is clear: males are innately aggressive but some societies have discovered how to modulate that dangerous instinct. So, what to do?

Consider sport. This week Robin van Persie, the Arsenal striker, was arrested on suspicion of rape, and regardless of the details of that case we know that sport today degrades. During the 19th century, under the influence of men such as Dr Thomas Arnold, of Rugby, Britain propagated a Corinthian view of amateur sports that promoted co-operation. But today we live in a world where professional sports promote an ethics-free obsession with ego and with winning above all else. Research papers such as Jeff Benedict and Alan Klein’s Arrest and Conviction Rates for Athletes Accused of Sexual Assault have chronicled some of the consequent moral squalor: sportsmen hit their women much more often than the rest of us. An official report from Clemson University, South Carolina, in 1998, noted that students most complained of sexual harassment from “athletes in particular and some male professors”.

But sportsmen are rational, and if they live in a world that rewards only winning then it is also because we have produced sportsmen who treat women as their private goods, and hit them. So we need, instead, to create a world where rational people learn to be good. That world is called the middle class, which is why crime, especially crime committed by young men, reflects the social classes. The poor have too few chances. This is seen at its most extreme in the US. Incredibly, according to a study of college freshmen (The Source of the River) by the sociologist, D. S. Massey, a third to a half of college age black men are in prison, on parole or under court supervision.

In Britain, the poor are short not of money but of control over their lives. Because they are not allowed to make enough important choices, their sons do not have the opportunity to learn the hazards of being bad. And it was the middle classes who took the workers’ autonomy away. In the 19th century, the schools, hospitals and social security systems were voluntary: created, paid for and controlled by ordinary people. They functioned well, as books such as James Bartholomew’s The Welfare State We’re In have chronicled. But the voluntary systems were nationalised, politicians and bureaucrats took control of them, while — under pressure from the taxpayer — their budgets failed to rise sufficiently.

If working-class boys inhabit a world where their schools, houses, hospitals and social security are free but inadequate, and where their legal incomes and legal pleasures are taxed, but their illegal ones, such as drugs, are not, how will they learn to be good? Will they not evolve into a Roman proletariat, whose irresponsibility is bolstered by free bread and vicious footballing circuses?

Young men are innately aggressive, but they are also rational, and it is for the rest of us to create incentives through which they learn to be good. Banning hoodies is not enough.

Terence Kealey is a scientist and vice-chancellor of the University of Buckingham

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