Novelist, playwright, and biographer Jean-Paul Sartre (1905-80) is widely considered one of the greatest philosophers of the twentieth century. His major works include "No Exit," "Nausea," "The Wall," "The Age of Reason," "Critique of Dialectical Reason," "Being and Nothingness," and "Roads to Freedom," an allegory of man's search for commitment, and not, as the man at the off-licence says, an everyday story of French country folk.