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In Harper Lee's To Kill a Mockingbird the author illustrates in the father/daughter relationship between Atticus and Scout a synergism in which a young Scout represents a raw, amorphous version of Maycomb society, hence allowing Atticus to do his main job of molding and educating both Scout and society about equality, tolerance, and justice.
Like the citizens of Maycomb, Scout discovers a new world around her with the proceedings of Tom Robinson's case. As the case progresses, so does the animosity among the people of the microcosmic universe that is Maycomb. Discord and confusion permeate a town which Scout herself later on describes as "old", "slow", and even lazy. Scout and Maycomb have both been shaken out of their comfort zones into a paradigm shift that unfolds them as people with a desperate need for social and psychological growth.
Atticus, in his talks with Scout, always ensures to leave a message. Notice how, while he never imposes his own view of things, he manages to juxtapose Scout's primitive and young views of the world with either an idea, a suggestion or an example that could suggest Scout to re-visit her original thoughts. For example, when Scout asks not to return to school, she is persuaded kindly, and not forcibly, by his charismatic persona and by the way in which he makes sense of what he says.
Atticus: Do you know what a compromise is?
Scout: Bendin' the law?
Atticus: [slightly bemused] Uh, no. It's an agreement reached by mutual consent. Now, here's the way it works. You concede the necessity of goin' to school, we'll keep right on readin' the same every night, just as we always have. Is that a bargain?
Had this not been a productive technique, we would have never heard Scout's personal account of the situation with Tom Robinson's trial years later and speaking from a more mature and reflective perspective.
Therefore, the author conveys the message of tolerance, equality and justice through the conversations between Scout and Atticus. Their dialogues are not meant to merely move the plot or entertain the audience; there is a wealth of messages, constructs, and paradigms that the very intellectually advanced Atticus effectively conveys into the mind of a growing Scout. This was done quite effectively, because it is Scout who narrates the tale in To Kill a Mockingbird looking back maturely and with insightful detail into the way that Maycomb may have been forever changed by Atticus Finch.
Therefore, the immature manner in which Scout first sees the world is allegorical to the immature way in which Maycomb, similarly saw it. The Atticus/Scout dialogues are allegorical to the Atticus/Maycomb interaction that takes place in the courtroom. Finally, the final reflection given by Scout in the narrative of the story is also allegorical to the potential changes in mind and spirit that the Tom Robinson trial, and Atticus's intervention, may have caused in the society of Maycomb, as a whole.