Contrast Gene's sense of responsibility with that of Phineas.

Gene and Finny, however close they are, are very different and in many ways, complementary beings. Gene is academic, Finny is athletic; Gene is a hard worker, Finny is not; Gene follows the rules, and Finny breaks them; Gene heeds authority figures, Finny does his best to ignore them. The pair get along very well, but they seem to have little in common aside from their differences. The differences in their natures and in their reactions to Finny's accident and to the war show them as foils, as their differences, taken together, make a vivid portrait of two very different people. Gene, however,carries a sense of guilt and responsibility for the entire story. Gene can't shake what he did by the tree that injured Finny.