Nausea is a fine exampleof Sartres train of thought. It delves into the profound and difficult questions of reality and existence through the eyes of an ordinary man.

Antoine is a very observant man. He writes very detailed accounts of what he sees and how interprets them based on his experiences and paradigm of thought. That is why, the text comes to the reader as rather boring and plain. The details are so fleshed out in his journals that it gives the reader the same atmosphere and feeling of complete and utter boredom that Antoine feels. Furthermore, it is because of this very observant nature that Antoine falls into despair.

From the start of the journal, we see that most of Antoines life is spent alone.. He frequents cafes where he observes other people, chatting away with their friends about all sorts of stories. Antoine becomes bitter and lonely as he continued to watch these youths happily weave their tales. However, he is frequented by the self-taught man. The self-taught man is always quite eager to ask and bug Antoine about various subjects such as adventures, ideas and opinions. Antoine despises the man for no apparent reason. It would always seem that Antoine is lonely but at the same time, feels boredom and irritation as he meets and converses with others. Anny, however, seems to be an exception to his apparent lack of enthusiasm for others. He holds on to the memories of times so spent with Anny but it does not ease his pain. As he delves deeper into his memories and dissects his encounters and letters to her that Antoine realizes the truth Anny does not love him even though he love her with all his heart.

Anotine is unemployed and spends most of his time writing a book about de Rollebon, a famous politician and alleged assassin of Paul I. Through his pre-occupation, he is able to counter the feeling of loneliness to some extent and alleviate boredom. However, as he continues his work, he starts to question validity of his sources. He notices the fact that some sources draw conclusions from the same facts. As the journal progresses, this questioning of the truth evolves into a question of reality. He becomes even more aloof, bored and despaired by the fact that reality is subjectively defined. The way he sees himself and the way others see him will always be different. The existence of one can be affirmed or denied by another.

Towards the end, Antoine comes to grips with the problem of defining existence. He soon realizes that existence can be defined by ones self. As he reads the paper regarding the raped girl, he understands the existence of this girl is no longer defined by her. Instead, the girl exists as people define that she does exist. In the same way, the street which he walks on or the apartment that he stays in exists not because of the fact that one can detect these objects with the five senses. Rather, these objects exist because Antoine recognizes them to exist. Finally, Antoine starts to feel somewhat at ease.

In summary, Nausea details the various existentialist concepts of Sartre. By using a story, Sartre is able to depict the elusiveness and troublesome nature of truth and existence.