Why is inequality so bad? It’s not just that the poorest people in highly unequal societies may go without food, shelter, or other basic subsistence goods. It’s not just that extreme inequality makes it difficult for the less fortunate to participate fully in their country’s social institutions. It’s not just that lavishing mansions, cars, and jewels on a few lucky people violates some primitive sense of justice and what’s fair. Although inequality may well be problematic for these conventional reasons, The Spirit Level tells us that it’s mainly bad because it makes status differences more extreme and salient and thus generates insecurity about our worth and where we stand in the social hierarchy. We should dislike inequality, in other words, because it produces anxiety and because such anxiety in turn leads to chronic stress, health problems, and other undesirable outcomes. The great achievement of The Spirit Level is documenting that this inequality-induced anxiety has so many bad effects. It makes humans feel stressed and deprived and more likely to get depressed, smoke, overeat, or engage in violent behavior. It also leads to conspicuous displays of consumption, such as buying fancy cars, big houses, and luxury clothes, all of which serve…