Although racial prejudice is important to the story, Boo Radley represents another type of prejudice. People fear and do not accept anyone who is different.
The entire neighborhood is judgmental and critical of Boo Radley. He’s an unusual man, because he has not been seen outside of his house since he was a teenager. The adults told stories about him, and the children were afraid of him.
The Radley Place was inhabited by an unknown entity the mere description of whom was enough to make us behave for days on end … (Ch. 1)
Arthur Radley was a fairly normal boy, but he had a troubled young adulthood. He was somewhat of a juvenile delinquent. His parents were very strict “foot-washing” Baptists. This might have affected the fact that he turned on them. The most famous (and perhaps apocryphal) incident was the scissors incident when Boo was thirty-three years old.
According to Miss Stephanie, Boo was sitting in the livingroom cutting some items from The Maycomb Tribune to paste in his scrapbook. His father entered the room. As Mr. Radley passed by, Boo drove the scissors into his parent’s leg, pulled them out, wiped them on his pants, and resumed his activities. (Ch. 1)
Boo Radley was kept in the courthouse basement, and then returned to the custody of his family and never seen again. Since this incident, the adults in the neighborhood gossiped about him. People like Stephanie Crawford told stories about him, such as that he was peeking into windows at night.
Actually, Arthur Radley was just quiet and shy and wanted to be left alone. He did not leave his house because he didn’t want to. Scout, Jem, and Dill shifted from thinking he was a monster to trying to be friends with him, and it paid off.