When we’re in the midst of a downturn that leads one’s thoughts back to the mass unemployment of the 1930s and when Karl Marx’s Das Kapital is suddenly topping the best-seller lists in Germany, it seems as though that old notion of class is making a comeback. In Britain, there are currently at least two art exhibitions focused on the issue of class in progress, and in the Guardian a few months ago Rafael Behr raised the question of whether we were headed for a new class struggle.

Yet it goes without saying that the variables today are quite different than they were during the Depression in the late 1920s. In Sweden, the old Conservative Party has created an image of itself as the new workers’ party, while one famous journalist with an aristocratic name not long ago defined herself as having come from the working class, given that her doctor parents had taught her it that pays to work hard. A growing number of carpenters and chefs are...