LitCharts assigns a color and icon to each theme in Nausea, which you can use to track the themes throughout the work.
Existence vs. Essence
Time
Love and Sexuality
Art and Legacy
Summary
Analysis
Roquentin re-reads the paragraph that first introduced him to the Marquis de Rollebon. The passage summarizes Rollebon’s success with women and involvement in political intrigue, culminating in his sudden imprisonment and eventual death. As he reads, Roquentin reflects on how much his interest in the Marquis has waned. He realizes that he’s no longer motivated to write his book because of the Marquis. Instead, he’s motivated by the act of writing itself. Roquentin wonders whether Rollebon was involved in the assassination of Paul I, but he suspects that “nothing can ever be proved.”
The paragraph on the Marquis de Rollebon suggests that the Marquis lived a life full of interest and adventure, unlike Roquentin’s own. It seems that Roquentin was motivated to write his book as a way of clinging to significance in his own life after he became disenchanted with travel, but his research is no longer doing the trick. His sustained interest in writing, however, foreshadows Nausea’s ending. It also seems appropriate, given that he continues to write in his journal with some enthusiasm.