In 1867, New York passed its first law to specifically regulate tenements. For the first time, they were required to have enough fire escapes, and a window in every bedroom — even if it only opened into another room. The law also required basement residences to have ceilings at least seven feet high and a window to let in light, among other things.

Many basements didn’t pass muster, but their tenants often refused to leave, wrote Jacob Riis in How the Other Half Lives, the seminal book on late-nineteenth century poverty in New York City. It took years for the police to drag all the “cave-dwellers” out of their illegal homes. Riis was unsympathetic. “To my mind,” he wrote, “to be put out of a tenement would be the height of good luck.”

Neoliberalism has turned Riis’s paternalism on its head: today, everyone should have the right to live in a cave. Libertarians clamor outright for more slums, arguing that regulations drive up costs and restrict choice. Moderates call for lowering the legal minimum size of an apartment so cities can solve their housing crises with “micro-units.”