As a child during the times recounted in the novel, Scout is innocent and impressionable; she observes and experiences instances of adult behavior and numerous events in Maycomb that are beyond her understanding. Scout turns to her father for answers to her many questions about what she has seen and heard. Atticus is her guide in making sense out of the world, and the lessons about moral integrity she learns from him become a part of her as she is growing up.
One particular scene in the novel's conclusion shows that Scout has learned well from Atticus and that she has achieved her own sense of moral integrity. When Atticus and Sheriff Tate discuss Boo Radley's having killed Bob Ewell to save Scout's and Jem's lives, the Sheriff insists that Boo's actions not be made public. Forcing the frightened, reclusive Boo into the glare of public attention would be cruel and senseless. Hearing their conversation, Scout says destroying Boo's security would be "like shootin' a mockingbird." Her father's earlier lesson about not shooting songbirds has translated for Scout into an understanding and respect for what is good in the world.
The injustice inflicted upon Tom Robinson at his trial and Tom's recent death have shaken her, and she understands the consequences of senseless destruction. Scout does not think in terms of "moral integrity," but she now knows it when she sees it and she embraces it.