In A Separate Peace, was it neccessary for Finny to die in terms of plot development? Why did Knowles feel Finny needed to die?

Finny's death plays an important part in Knowles' developing his themes in the novel. Finny's character is developed to symbolize the innocence of youth, among other interpretations; his death then works symbolically to represent the destruction of innocence for his generation as they are rushed into the war. Finny's death also serves to advance the development of Gene's character. It is through Finny's death that Gene comes to his final insights into his own character and, by extension, his deeper understanding of human nature itself. Also, the fact that Finny dies works thematically with the idea that Finny's goodness and joy could not exist for very long in a world filled with hate and conflict. Finny acts as the central symbol in the story; consequently, he is the only character in the novel to whom Knowles does not give a last name.