Philosophers of all ages have had to come to terms with the existence of God. If God exists then ideas of philosophy such as determinism and a perfect ideal of existence are concepts which can be effectively discussed. However, if there is no God, then there is no higher moral power to strive for, no meaning to living than life itself. While many philosophers starting in the 18th century began to conceive of a world where God did not in fact exist, most were not willing to give up the idea that a code of being still existed in some perfect, objective form. What existentialists like Jean-Paul Sartre did was to expose the falseness of any system of values in a world where God does not exist.In “Existentialism and Humanism,” Sartre writes that there is no possible concept of values existing a priori to what we make of them. He describes a French movement that attempted to posit that even without the ideal of God, values could still exist: “nothing will be changed if God does not exist” (“Existentialism and Humanism,” 40). However, as Sartre posits, the inexistence of God changes everything. If there is no God then there are no a priori notions of good or bad, no ideals of existence which men do not create for themselves. While many critics of Existentialism posit that this philosophy takes agency and power away from man, rendering all actions and thoughts arbitrary, Sartre sees this philosophy instead as empowering: while man does not determine his own existence, he has the power to use his own life in any way he chooses.Sartre’s first and most famous philosophical novel, Nausea, tells the story of a man coming to terms with this subjective reality of his life. Antoine Roquetin, the novel’s, hero (or anti-hero), must face the central claim of existentialism: that if there is no God, then man’s existence precedes his essence: “man exists, turns up, appears on the scene, and only afterwards, defines himself….Man is nothing else but what he makes of himself” (36). Roquetin gets “the nausea” as he begins to realize the idea that in everything existence precedes essence, or that he, as a man, is capable of and responsible for defining everything he sees; that there is no essence, be it to objects, feelings or memories that is anything but what a subjective individual makes of them. The Nausea is a visceral, undigested realization that becomes less and less physical as Roquetin begins to accept this realization and live his life accordingly.Antoine first gets the Nausea, or realizes that existence precedes essence, through his connection with the color of objects. Color takes on a very important role in this novel because color is the essence of essence. When describing an object, its color is often the first thing we refer to, and yet, what is more subjective than color? How is one to know that his definition of red is the same as someone else’s? It is impossible to know that when I say something is red, and another person agrees with me, that he or she is not actually seeing what I call blue. Antoine writes of an experience in his favorite café. He is watching the bartender and notices his suspenders: “the suspenders can hardly be seen against the blue shirt…but it is false humility; in fact they will not let themselves be forgotten…as if, starting to become purple, they stopped somewhere along the way without giving up their pretensions….The Nausea is…in the suspenders” (Nausea, 19). Antoine’s nausea is a physical reminder that he is attempting to define the suspenders as purple, as though purple were an objective reality and the meaning of their existence. However, the purpleness of the suspenders is entirely subjective: they are purple because Roquetin makes them so.His statement that the Nausea exists within the suspenders exhibits his refusal to accept the responsibility that comes with admitting the control he has over the essence of these suspenders. However, we see his acceptance of this fact later in the novel. In the climax moment, when Antoine fully accepts that existence precedes essence and that color itself does not exist, he writes: “Adolphe’s suspenders….They were not purple” (130). To say that the suspenders were purple as he initially does, suggests that purple can be held up to some ideal of purple that exists for all men. To say that the were not purple does not mean that they were some other color, but that their existence has nothing to do with their being purple, the suspenders, like all objects exist without any defining values, those values are assigned by each man as he chooses.The nausea that Antoine feels outside himself when looking at the suspenders, becomes a nausea he feels within himself as he begins to consider his attempts to write a biography of an historical figure named Robellon. He has spent the better part of his life writing on this man, trying to figure out who he was. However, just as he realizes that the suspenders in the café simply exist, without any value that objectifies them, he also comes to the same conclusion on the subject of Robellon’s life. He comments early in the novel that in the ten years he has studied this man he still cannot objectively define him: “what is lacking in all the testimony [about Robellon] is firmness and consistency…they do not seem to be about the same person” (13). What Roquetin is realizing is that he will never find a higher truth about Robellon then what he decides to believe about him.In fact, he realizes that all historians define history; that there is no more objective truth to be found in the past than in the present. A biography of Robellon’s life would be no more truthful than a fictional account. This sickening realization that the past ten years of Roquetin’s life has been spent in attempting to find an ultimate truth from the past leads him to another important tenant of existentialism one which we might call presentism: “the true nature of the present revealed itself: it was what exists….The past did not exist…things are entirely what they appear to be and behind them…there is nothing” (96). Right after the acceptance of this realization Roquetin thinks he is getting the Nausea again, but instead he writes “it wasn’t that….M. Robellon had just died for the second time” (96). The past does not exist, it only lives on through subjective memory, thus Roquetin must accept the notion that he will never truly “know” Robellon, just as he will never truly know himself in the past. He thinks he feels the Nausea because it is his usual reaction to the realization of existence, but in this instance he has already accepted that the past is a void, thus he does not displace his conscious realization with a physical pain.The realization that the past is a void also leads Roquetin to the realization that the future to means nothing objectively. If we can determine nothing from the past, then looking towards the future is just as useless, for any action we take with an eye to the future will no longer exist once the future is present. The very idea of a future implies that the past remains alive, this becomes clear to Roquetin as it applies to his personal life. He receives a letter from a past lover, Anny, who wants to see him in a few weeks. As he thinks back upon his relationship with this woman, he attempts to regain the feeling of love he had for her in the past. He particularly harps upon her notion of “perfect moments,” or moments of objective perfection. He remarks that he was never able to understand this notion, a clue that he had always subconsciously realized that existence could never be justified objectively. However, he still holds on to this meeting with Anny, as though if she can explain the notion of perfect moments to him, it might relieve him of the nausea of existence.When he sees Anny, he is hit, full force, with the notion that his reliance on the past and his looking toward the future are as futile in the present as the notion of a perfect moment. The essence of Anny, the memories of her, represent Antoine’s attempts to place her in some spectrum of value in his life that no longer exists. In fact, since she is nothing but a memory for him, she barely exists: “I can hardly make out the pale spot of her face…Anny is sitting opposite to me, we haven’t seen each other for four years and we have nothing more to say” (153). There is no way for Antoine to relate to his old lover, nor any justification for his having looked forward to their meeting; his only notions of her are from the past, a past which no longer has any value in his life. Ironically, at this most startling realization, Antoine no longer feels the Nausea. In fact, a few pages later he remarks that: “the Nausea has given me a…breathing spell” (157). In fact, while he believes the Nausea will return, it does not, it has become a part of Antoine’s consciousness, existence in all of its rawness has shown itself to him and in accepting that there is nothing more than today, nothing more than what he perceives, Antoine has rid himself of the sickness that the abnegation of this realization brought on.At the end of the novel, there is more than just the recession of the Nausea to encourage Antoine to live though he has learned that there is no higher calling or truth to justify his existence. As he is sitting once again in his favorite café, on the day he is leaving his town for good, he listens to a jazz record that he loves. He begins to imagine the man who wrote the song and the woman singing it and sees that there is in fact a possibility for justification of existence even within existentialism: he realizes that he has the power to create, to make something in the world that can stop time and the pain of existence the way jazz does for him: “A novel. And there would be people who read this book…and they would think about my life as…something precious” (178). He could live on in the present minds of others and thereby justify his life.Sartre writes in “Existentialism as Humanism,” that art and values are very similar: “what art and ethics have in common is that we have creation and invention in both cases” (55). In Nausea he shows that art, as an admitted creation of man, something which never is held up to an objective truth, is a way for an individual to express his essence. This form of expression has the power to help others make something of their existence, and in that way justify the artist’s existence as well. This is the most powerful proof that existentialism is in fact a philosophy of optimism and action rather than pessimism and inaction. Existentialists do not believe that existence can be held up to and compared to some higher system of values, but they do believe that within our own creation of a subjective system of values we can and must invent meaning for ourselves and for others.