Think of Paris and think of intellectuals and one is almost inevitably reminded of Jean-Paul Sartre and Simone de Beauvoir. For good or ill, they established what it meant to be an intellectual in France. It was to embrace the myth of the Left: to be against capitalism, soft on communism and the Soviet Union, hostile towards the United States, to support the struggle against colonialism, to believe in the proletariat and in revolution. Above all, it was to display "commitment".

If this posturing exercised a near monopoly during the Cold War, its roots were clearly discernible during the interwar years. In 1927, Julien Benda published what was to become one of the most famous books of this time, La Trahison des Clercs. Benda's complaint was that intellectuals had subordinated their lofty mission "to the service of their political passions", abasing the abstract values of truth and justice before those of action. By doing nothing to resist the passions of race, class and nation, he argued, modern intellectuals had proclaimed that the intellectual function was respectable only to the extent that it pursued concrete advantage and that an intelligence disinterested in these ends was to be scorned.

The response to this plea for intellectuals to recover their vocation came in the form of Les Chiens de Garde, published by Paul Nizan, a Marxist, in 1932. "Every philosopher," Nizan wrote, "though he may consider that he does not, participates in the impure realities of the age." Thus Benda's talk of abstract verities was less a choice made by eternal man than the decision of a partisan. For Nizan, the alternative facing the intellectual was a simple one. He was either for the oppressed or for the oppressors. "If we are to betray the bourgeoisie for the sake of mankind," he wrote, "let us not be ashamed to admit that we are traitors."