I would want to answer this question by pointing out the way in which Mitty, in his desperate desire to escape from his humdrum existence and his terrible wife, gives normal, everyday objects and actions symbolic significance as they trigger off his series of daydreams. Note the way in which driving past the hospital after he has dropped off his wife symbolically gives rise to his daydream about performing a major operation. Likewise hearing a newsboy talking about a trial triggers his daydream of standing up in court and testifying. At each stage of the story, Mitty is forced to take the boring, monotonous details of his existence and give them symbolic significance to enable him to embark on his flights of fancy and get the release and freedom that he does not have in life. Thus the symbolism in this excellent short story lies in the symbolism that Mitty gives objects and actions, such as in the last daydream:
He stood up against the wall of the drugstore, smoking... He put his shoulders back and his heels together. "To hell with the handkerchief," said Walter Mitty scornfully. He took one last drag on his cigarette and snapped it away. Then, with the faint, fleeting smile playing about his lips, he faced the firing squad; erect and motionless, proud and disdainful, Walter Mitty the Undefeated, inscrutable to the last.
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