This excellent study of the friendship and break between Albert Camus and Jean-Paul Sartre deals with a subject that goes far beyond intellectual history; it illuminates choices that millions of French readers have personally had to make. Although both grew up without fathers, the two men came from very different milieus: Sartre was bourgeois (and hated it), whereas Camus was raised in Algeria by an illiterate mother. Camus' political involvement grew out of his concern for the lives of the Algerian poor; Sartre was drawn to politics only after spending time in a World War II prison camp, long after he had won acclaim as a philosopher and novelist. When France was liberated, the two men became the country's leading new intellectuals and heralds of existentialism (a label Camus never accepted), and over the next 15 years-until Camus' accidental death in 1960-they figured in a kind of three-act politico-intellectual play, which Aronson recounts with erudition, empathy, fairness, and elegance. At first, Camus and Sartre were close friends united by common experience in the Resistance, promoting social change while evincing a clear-eyed determination to face the ethical and political dilemmas of a somber universe. The great issue that began to divide them in the 1950s was communism, and the 1952 publication of Camus' The Rebel led to their break. Their opposing views on violence subsequently led them to react differently to war in Algeria, with Sartre accepting violent means as an acceptable tool in the fight for decolonization while Camus, horrified by the atrocities of both sides, stayed silent in public. Ultimately, of course, neither silence nor shrillness had any impact on the course of events.