Summary of Jean-Paul Sartre's Contributions to Philosophy

Jean Paul Sartre (1905-1980) was a philosopher among other vocations (including novelist, playwright, and literary critic) and was also at the forefront of 20th century French philosophy and Marxism but is mainly considered an existentialist and is a key figure in that area of philosophy. At the outset Sartre?s philosophy was influenced by Edmund Husserl, the phenomenological movement and the idea that consciousness is about objects rather than creating within it an inner representation of the object, but he expands on these ideas and gives his own spin as his body of works grows.
In 1938 Sartre published one of his earliest and most well-known works is La Naus?e (Nausea) which depicts a frustrated historian (Antoine Roquentin) who feels nausea as a result of his struggle to define himself despite the distractions of inanimate objects and situations which he believes detract from that goal, end he even fears whether his existence is a figment of the imagination. This novel is often considered a manifesto of existentialism and is sometimes seen as one of the canonical works of the movement. It brings up questions of existence, objects in relation to consciousness, freedom, and the meaning of life.
Shortly after publishing this work Sartre also wrote an essay called The Transcendence of the Ego in which he expanded on the idea that objects exist independently from our consciousness of them and added the idea that a person?s ego is itself an object of consciousness to be discovered.
His main existentialist work however is called Being and Nothingness: An Essay on Phenomenological Ontology and was published in 1943. Its writing was spurred but Sartre?s reflections as a result of reading Martin Heidegger?s Being and Time, an ontological work from a phenomenologist perspective, which prompted Sartre?s subtitle for his work. He analyzes and criticizes the works of other philosophers and uses these to summarize his theory of being, consciousness and phenomena. One of Sartre?s most original contributions to metaphysics is found in this work and is his concept of ?nothingness? and the idea that it is essential to being. He also talks about ?being? in two sense using Hegel?s terminology (pour-soi/for-itself, and en-soi/in-itself) and talks about the in-itself existing independently and transcending the for-itself.