Gabriel Marcel has been described as a theistic or Christian existentialist. Born in Paris of Protestant parents, he converted to Roman Catholicism in 1924. Prior to his conversion, he had immersed himself in idealism, as his first book, a study of Royce's metaphysics, reveals. Before Jaspers and Heidegger were known to French intellectuals, Marcel had written about themes central to existentialism, but with a religious twist. He had acknowledged concern for the vitality and pervasiveness of religious experience, and, like Martin Buber, he had pointed to the sociality of human experience, which bears witness to the presence of the Divine. For Marcel, Being involves participation. No one can be separated from the whole of Being to which he or she is related. Nor can a person be reduced to merely a facet of Being; for he or she is a concrete individual, with experience that is immediate, spontaneous, unpredictable. Though entranced by the mystery of existence, a person may illuminate it by means of philosophical reflection.
Sartre is the dominant figure in post-war French intellectual life. A graduate of the prestigious Ecole Normale Superieure with an agregation in philosophy, Sartre has been a major figure on the literary and philosophical scenes since the late 1930s. Widely known as an atheistic proponent of existentialism, he emphasized the priority of existence over preconceived essences and the importance of human freedom. In his first and best novel, Nausea (1938), Sartre contrasted the fluidity of human consciousness with the apparent solidity of external reality and satirized the hypocrisies and pretensions of bourgeois idealism. Sartre's theater is also highly ideological, emphasizing the importance of personal freedom and the commitment of the individual to social and political goals. His first play, The Flies (1943), was produced during the German occupation, despite its underlying message of defiance. One of his most popular plays is the one-act No Exit (1944), in which the traditional theological concept of hell is redefined in existentialist terms. In Red Gloves (Les Mains Sales) (1948), Sartre examines the pragmatic implications of the individual involved in political action through the mechanism of the Communist party and a changing historical situation. His highly readable autobiography, The Words (1964), tells of his childhood in an idealistic bourgeois Protestant family and of his subsequent rejection of his upbringing. Sartre has also made significant contributions to literary criticism in his 10-volume Situations (1947--72) and in works on Baudelaire, Genet, and Flaubert.