This video originally appeared on Aeon and has been reprinted here with permission.
In the wake of World War II, French existentialists Jean-Paul Sartre and Albert Camus were close friends. They drank and argued together, often spending long nights out on the town. All around them, Paris was being rebuilt. Through their writing, Sartre and Camus hoped to guide the new France toward a more equitable future. They became celebrities, their every movement reported in the papers. But it was not to last.
In 1952, the men fell out bitterly, and their disagreement became the philosophical feud of the century. The video above explores what happened—and how two close friends devolved into some of history's most unforgiving enemies.