In John Knowle's A Separate Peace, symbols are used to develop and advance the themes of the novel. One theme is the lack of an awareness of the real world among the students who attend the Devon Academy. The war is a symbol of the "real world", from which the boys exclude themselves. It is as if the boys are in their own little world or bubble secluded from the outside world and everyone else. Along with their friends, Gene and Finny play games and joke about the war instead of taking it seriously and preparing for it. Finny organizes the Winter Carnival, invents the game of Blitz Ball, and encourages his friends to have a snowball fight. When Gene looks back on that day of the Winter Carnival, he says, "---it was this liberation we had torn from the gray encroachments of 1943, the escape we had concocted, this afternoon of momentary, illusory, special and separate peace" (Knowles, 832). As he watches the snowball fight, Gene thinks to himself, "There they all were now, the cream of the school, the lights and leaders of the senior class, with their high IQs and expensive shoes, as Brinker had said, pasting each other with snowballs"(843).
             Another of the principal themes in this novel is the theme of maturity. The two rivers that are part of the Devon School property symbolize how Gene and Finny grow up through the course of the novel. The Devon River is preferred by the students because it is above the dam and contains clean water. It is a symbol of childhood and innocence because it is safe and simple. It is preferred which shows how the boys choose to hold onto their youth instead of growing up. The Naguamsett is the disgustingly dirty river which symbolizes adulthood because of its complexity. The two rivers intermingle showing the boys' changes from immature individuals to slightly older and wiser men.
             Sooner or later, Gene and Phineas, who at the beginning of the novel are extremely immature, have to face reality....