A public library is predicated on an ethos of sharing and egalitarianism. It is nonjudgmental. It stands in stark opposition to the materialism and individualism that otherwise define our culture. It is defiantly, proudly, communal. The sociologist Eric Klinenberg reminds us that libraries were once called palaces for the people. Klinenberg is interested in the ways that common spaces can repair our fractious and polarized civic life. And though he argues in his new book that playgrounds, sporting clubs, diners, parks, farmer’s markets, and churches—anything, really, that puts people in close contact with one another—have the capacity to strengthen what Tocqueville called the cross-cutting ties that bind us to those who in many ways are different from us, he suggests that libraries may be the most effective.