To Kill a Mocking Bird.

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…assumptions about other people who they do not know about. People judged him according to what they had heard. Boo proved to be a mockingbird by saving the lives of Jem and Scout, and that ultimately changed their views of him. Throughout this novel, the mockingbird symbolizes good people who were nice and never did any harm. To kill or harm then would be sin, because mockingbirds make the world a better place to live.