“The findings of those statisticians’ successors—that poor children are more likely to fail at school, poor adults to commit crimes and die young, and so on—are nowadays uncontroversial. And policymakers mostly eschew metaphysics. Instead, they try to break such links by spending to “end child poverty” and by targeting health and education initiatives on the neediest. Yet such attempts are doomed to disappoint, say British social scientists, Richard Wilkinson and Kate Pickett, because they conceive of each social ill in isolation, rather than treating their shared root cause. Moreover, they misidentify that cause: it is not poverty as such, but inequality.

It is a sweeping claim, yet the evidence, here painstakingly marshalled, is hard to dispute. Within the rich world, where destitution is rare, countries where incomes are more evenly distributed have longer-lived citizens and lower rates of obesity, delinquency, depression and teenage pregnancy than richer countries where wealth is more concentrated. Studies of British civil servants find that senior ones enjoy better health than their immediate subordinates, who in turn do better than those further down the ladder.

And the evidence is that the differences in status cause these “gradients”. Low-caste Indian children do worse on cognitive tests if they must state their identities beforehand. High-status baboons bred in captivity show elevated levels of stress hormones and become ill more often when they are moved to groups where they no longer dominate.

What to do about this sickness caused by other people’s wealth? Swingeing taxes on the rich, or smaller differences in pay in the first place, say the authors, citing Sweden and Japan as instances of the two alternatives. A decade ago even left-wing politicians were “intensely relaxed about people getting filthy rich”. Now, as it becomes clearer that some of the rich got that way by theft, the idea that they have also caused injury more subtly will gain a readier hearing.”

The Economist recenserar boken The Spirit Level: Why More Equal Societies Almost Always Do Better av Richard Wilkinson och Kate Pickett. “Social Inequality: Always With Us“, 26 februari.

/Erik Bengtsson, GSHF och Libertas redaktion