Being and Nothingness

Sartre's major philosophical treatise, published in 1943 with the subtitle 'An Essay on Phenomenological Ontology'. Building on Husserl and Heidegger, it divides reality into being-in-itself, the solid, self-identical being of things, and being-for-itself, consciousness, which is never simply what it is. Consciousness brings nothingness into the world: looking for Pierre in a café, I experience his absence. This gap is our freedom, and the anguish of freedom leads to bad faith, the attempt to deceive oneself about it, illustrated by a café waiter playing at being a waiter. Part Three analyses being-for-others: through the look, as when someone catches me peering through a keyhole, I feel shame and become an object for another, and Sartre treats love, desire, hate and sadism as forms of conflict. The last part argues that freedom is total but always in a situation, and ends with existential psychoanalysis and the claim that man is a useless passion.

It is the fullest statement of existentialist ideas about freedom, self-deception and other people, and its descriptions of bad faith and the look are still used in philosophy, psychology and literature.