Themes are the fundamental and often universal ideas explored in a literary work.
The most important theme of To Kill a Mockingbird is the book’s exploration of the moral nature of human beings—that is, whether people are essentially good or essentially evil. The novel approaches this question by dramatizing Scout and Jem’s transition from a perspective of childhood innocence, in which they assume that people are good because they have never seen evil, to a more adult perspective, in which they have confronted evil and must incorporate it into their understanding of the world. As a result of this portrayal of the transition from innocence to experience, one of the book’s important subthemes involves the threat that hatred, prejudice, and ignorance pose to the innocent: people such as Tom Robinson and Boo Radley are not prepared for the evil that they encounter, and, as a result, they are destroyed. Even Jem is victimized to an extent by his discovery of the evil of racism during and after the trial. Whereas Scout is able to maintain her basic faith in human nature despite Tom’s conviction, Jem’s faith in justice and in humanity is badly damaged, and he retreats into a state of disillusionment.
The moral voice of To Kill a Mockingbird is embodied by Atticus Finch, who is virtually unique in the novel in that he has experienced and understood evil without losing his faith in the human capacity for goodness. Atticus understands that, rather than being simply creatures of good or creatures of evil, most people have both good and bad qualities. The important thing is to appreciate the good qualities and understand the bad qualities by treating others with sympathy and trying to see life from their perspective. He tries to teach this ultimate moral lesson to Jem and Scout to show them that it is possible to live with conscience without losing hope or becoming cynical. In this way, Atticus is able to admire Mrs. Dubose’s courage even while deploring her racism. Scout’s progress as a character in the novel is defined by her gradual development toward understanding Atticus’s lessons, culminating when, in the final chapters, Scout at last sees Boo Radley as a human being. Her newfound ability to view the world from his perspective ensures that she will not become jaded as she loses her innocence.
Because exploration of the novel’s larger moral questions takes place within the perspective of children, the education of children is necessarily involved in the development of all of the novel’s themes. In a sense, the plot of the story charts Scout’s moral education, and the theme of how children are educated—how they are taught to move from innocence to adulthood—recurs throughout the novel (at the end of the book, Scout even says that she has learned practically everything except algebra). This theme is explored most powerfully through the relationship between Atticus and his children, as he devotes himself to instilling a social conscience in Jem and Scout. The scenes at school provide a direct counterpoint to Atticus’s effective education of his children: Scout is frequently confronted with teachers who are either frustratingly unsympathetic to children’s needs or morally hypocritical. As is true of To Kill a Mockingbird’s other moral themes, the novel’s conclusion about education is that the most important lessons are those of sympathy and understanding, and that a sympathetic, understanding approach is the best way to teach these lessons. In this way, Atticus’s ability to put himself in his children’s shoes makes him an excellent teacher, while Miss Caroline’s rigid commitment to the educational techniques that she learned in college makes her ineffective and even dangerous.
Differences in social status are explored largely through the overcomplicated social hierarchy of Maycomb, the ins and outs of which constantly baffle the children. The relatively well-off Finches stand near the top of Maycomb’s social hierarchy, with most of the townspeople beneath them. Ignorant country farmers like the Cunninghams lie below the townspeople, and the white trash Ewells rest below the Cunninghams. But the black community in Maycomb, despite its abundance of admirable qualities, squats below even the Ewells, enabling Bob Ewell to make up for his own lack of importance by persecuting Tom Robinson. These rigid social divisions that make up so much of the adult world are revealed in the book to be both irrational and destructive. For example, Scout cannot understand why Aunt Alexandra refuses to let her consort with young Walter Cunningham. Lee uses the children’s perplexity at the unpleasant layering of Maycomb society to critique the role of class status and, ultimately, prejudice in human interaction.