Sandel is now a renowned professor at Harvard, but we first became friends when we grew up together in Minneapolis in the 1960s. Both our fathers took us to the 1965 World Series, when the Dodgers beat the Twins in seven games. In 1965, the best tickets in Metropolitan Stadium cost $3; bleachers were $1.50. Sandel’s third-deck seat to the World Series cost $8. Today, alas, not only are most stadiums named for companies, but the wealthy now sit in skyboxes — even at college games — that cost tens of thousands of dollars a season, and hoi polloi sit out in the rain.

Throughout our society, we are losing the places and institutions that used to bring people together from different walks of life. Sandel calls this the “skyboxification of American life,” and it is troubling. Unless the rich and poor encounter one another in everyday life, it is hard to think of ourselves as engaged in a common project. At a time when to fix our society we need to do big, hard things together, the marketization of public life becomes one more thing pulling us apart. “The great missing debate in contemporary politics,” Sandel writes, “is about the role and reach of markets.” We should be asking where markets serve the public good, and where they don’t belong, he argues. And we should be asking how to rebuild class-mixing institutions.