A Separate Peace: Motifs 2 key examples

At the beginning of the novel Gene is fixated on Finny’s physicality. His body is strong, compact, and attractive, and looking at him makes Gene feel an uncomfortable combination of admiration and jealousy. Finny is a natural athlete, which is part of his easy confidence with other people. These are traits that Gene respects but also make him feel resentful because they highlight his own—perceived—limitations. This mixture of feelings about Finny’s body drives Gene's rivalry with him throughout their lives together.

Finny’s initial injury—a shattered leg after falling from the Super Suicide Society of the Summer Session’s tree—significantly changes his relationship with Gene. Because Gene shook the branch, he feels responsible for how badly Finny gets hurt. Finny’s later and more deadly injury—falling down the stairs and re-breaking his leg after the “show trial”—feels to Gene like a continuation of the consequences of shaking the branch Finny stood on. He didn’t “kill” Finny the first time, but Gene feels responsible for his death when another fall eventually kills his friend. The consequences of the first injury result in notable changes for both characters. Finny's loss of physical prowess makes Gene feel a horrible mixture of superiority and shame. In a sense, the boys switch places after Finny is maimed. Finny is forced to rely on his intellect instead of his body, and Gene decides to train for the Olympics in Finny's place. 

For adolescent boys like the students of the Devon School, physical growth is often accompanied by a heightened awareness of their own bodies in relation to others. In the case of Gene and Finny, the stark contrast in their physicalities—Finny’s golden, muscular body versus Gene’s more average build—intensifies Gene’s feelings of inadequacy and jealousy. Because they spend so much time together, this constant comparison to Finny become intertwined with Gene's self-image. His simultaneous attraction to and resentment of Finny are behind a lot of the confusion and misery he experiences.

Furthermore, the novel sets these internal personal transformations against the backdrop of World War II. This was a time when the world at large was acutely aware of the bodies of young men. In previously unknown numbers, those bodies were relentlessly examined for physical fitness and battle-readiness, forced into combat, and bombed or shot to death. For the second time in the beginning of the 20th century almost an entire generation of young men was lost or injured in global war. This broader societal context adds a layer of urgency and gravity to the physical changes Finny, Gene, and their friends undergo. The characters are not only dealing with the normal insecurities, sexual confusion, and competitive dynamics of adolescence but are also facing the imminent demands of wartime service.

The tension between them builds as Gene misinterprets Finny’s actions, assuming that Finny’s confidence and ease with other people is also hiding a desire to outshine Gene academically. This belief is part of what motivates Gene’s destructive choice to jounce the branch when he and Finny climb the tree together to jump into the river. Because of the way his rivalry with Finny motivated this impulsive mood, Gene feels that Finny’s injury is the physical consequence of his own jealousy and competitiveness. Because of how badly Finny’s leg is injured, he loses his ability to excel at sports, removing a great deal of his social currency and affecting how the other boys perceive him. The incident irreparably alters Gene and Finny’s relationship, even after Finny accepts Gene's apology for jiggling the branch. Finny's damaged leg hurts both boys terribly, though in different ways. For Gene, it magnifies his sense of inadequacy and his worry that Finny is a better person than he is. For Finny, losing his physical abilities is also a loss of the physical power and ease that he feels defines him. His confidence in himself is fundamentally shaken. 

As an adult Gene acknowledges the role that their “friendly” rivalry played in Finny’s death and revisits the reasons for his own behavior, he’s able to reconcile a little of his guilt about Finny’s death. He sees, through his flashbacks, that the rivalry was not one-sided and that not all of the blame for Finny’s accidents lies with him. This realization, however, does not undo the actual damage their relationship caused; it just lets Gene see that love and jealousy aren’t mutually exclusive states.