What lesson do the Finch children learn from the mad dog incident in To Kill a Mockingbird? Explain how it changed their understanding of their father. Is the mad dog a symbol of the people of Maycomb?
Scout begins narrating Chapter 10 by discussing the perception she and Jem have of their father. Prior to the dog incident, they viewed him as an old man. That Atticus was a man of words did not impress them much; they felt he was not a man of action and therefore not as "manly" as the other children's younger fathers:
Atticus was feeble: he was nearly fifty. When Jem and I asked him why he was so old, he said he got started late, which we felt reflected upon his abilities and manliness.
Our father didn’t do anything. He worked in an office, not in a drugstore. Atticus did not drive a dump-truck for the county, he was not the sheriff, he did not farm, work in a garage, or do anything that could possibly arouse the admiration of anyone.
When Atticus forbade Scout from fighting, she believed this was another sign of weakness and made her look weak to her peers.
Miss Maudie offers some encouragement. She explains how well Atticus can construct a will, how well he plays checkers, and how he can play a Jew's Harp. But none of these things impress Scout.
When Atticus shows some physical ability, shooting Tim Johnson (the dog) with one shot, the children's perception of him changes. For the first time, they see that he can be a man of action. Following the dog incident, Scout wants to brag about it at school. But Jem realizes that Atticus would not want them to brag. As Miss Maudie said:
I think maybe he put his gun down when he realized that God had given him an unfair advantage over most living things. I guess he decided he wouldn’t shoot till he had to, and he had to today.
Atticus has no need to brag or show off. He uses his abilities when necessary. Jem, being older, begins to realize that Atticus' humility and character are as admirable as scoring touchdowns. Being a man of words and character is as admirable as being a man of action. He says, "Atticus is real old, but I
wouldn’t care if he couldn’t do anything—I wouldn’t care if he couldn’t do a
blessed thing." It seems that now, Jem is proud of who Atticus is; no longer wishing that Atticus was a younger, bragging father.
The dog, Tim Johnson, is referred to as "the pet of Maycomb." It would be a stretch to suggest that the dog is a symbol of Maycomb. But an argument could be made that an old dog, sick with a distorted perception of things is analogous to an old town, sick with racist traditions.
Here is the scene of the movie adaptation that shows the mad dog incident: