Pay attention to the book title and the chapter titles. This may seem like an obvious and simple point, but titles often represent clues about the theme or themes that structure the story. In some cases, the titles presents the themes in a straightforward way that requires little interpretation. In other cases, the titles themselves may be mysterious or puzzlelike. One useful trick for identifying a theme in a novel is to find out why the author chose the title. Jean Paul Sartre's novel "Nausea" is a good example. "Nausea" is novel that presents Sartre's existentialist philosophy in literary form. The main protagonist, Antoine Roquentin, engages in a search for meaning in a meaningless world. Confronted with bare meaningless and contingent existence makes him nauseous.
Focus on what the main hero and the other characters in the story or novel are doing. Their actions, motivations, impulses, success or failures are all central to the themes that underlie the story. One of the major themes in F. Scott Fitzgerald's novel "Tender Is The Night" is mental illness or instability. It is represented in the two main characters, Dick Diver and his wife Nicole. Diver is a psychologist who meets Nicole while she is a patient in Switzerland.
Concentrate on the specific details or characterization of the individuals in the story. The manner in which the protagonist is portrayed also serves to outline the basic themes in the story. Another Fitzgerald novel, "The Great Gatsby," presents the protagonist in an ambiguous light. On the one hand, Jay Gatsby seems to be a interesting, self-made character who is motivated by pure love for Daisy Buchanan. On the other hand, Gatsby has a shadier side and his love for Daisy seems more like an unhealthy obsession. Different aspects of Gatsby's character and past are gradually revealed as the novel unfolds.
Identify the central conflicts in the story. A short story or a novel may revolve around one central conflict or several conflicts. One of the central conflicts in "The Great Gatsby" is the conflict between old money, represented by Daisy Buchanan and her husband Tom, and the newly rich, represented by Gatsby. The Buchanans live in the village of East Egg on Long Island. Gatsby and his peers live in the village of West Egg. East Egg and West Egg are separated by a bay.
A larger novel may revolve around multiple themes, and the conflict among the themes may be indicative of a more general theme. Tolstoy's novel "Anna Karenina" revolves around numerous characters, plots and subplots and it is easy to get lost in the details of the story. However, focusing on the relationships between the conflicts and plots reveals that Tolstoy's main concern in the novel was to critique the social world and mores of the upper crust of 19th-century Russia. The motivation for the critique was Tolstoy's desire to present an alternate vision of the good life.