Two fundamental notions dominate Sartre’s work «L’être et le néant» («Being and Nothingness», first published in Paris, 1943) that of ontological investigation and that of moral determinism: on the basis of the former Sartre intends to reject the latter, i.e. to reject any attempt to give moral determinism a ground. There is moral determinism any time a cause / effect relation or a premise / consequence relation is applied within the sphere of « human reality» and human action. Where choices are, moral determinism can’t see but effects or consequences. Sartre draws attention to the fact that we have two kinds of moral determinism, depending on where the causes are considered to be. If they are in the world around (see his critical remarks on Marxist materialism, p.626) or in some preceding action we did, we have what Sartre names horizontal determinism. If they are psychological or physiological tendencies, concealed in the libido of the subject (see his critical remarks on Freud, p.502 ff.), we have what Sartre names vertical determinism. Since the two both mistake the world of man with the world of things, Sartre engages in an investigation meant to discover what the general features of the «human reality» are and how can an object en général exist for the conscience (see for i. p. 212).