Scout’s opinion of Boo Radley changes from fear and curiosity to empathy and understanding.
At the beginning of the story, Scout is only about six years old. Like most kids in the neighborhood, she is suspicious of the Radleys, and especially curious and frightened when it comes to Boo.
Jem gave a reasonable description of Boo: Boo was about six-and-a-half feet tall, judging from his tracks; he dined on raw squirrels and any cats he could catch, that's why his hands were bloodstained … (ch 1)
When Dill joins them, the Finch children spend a lot of time re-enacting the Radley story and trying to make Boo come out. Soon he begins leaving them notes, and even puts a blanket on Scout’s shoulders when she is standing outside at the fire.
When Boo saves Scout and Jem from Bob Ewell, she finally gets to meet him. She finds him gentle and shy. When she walks him home, she stands on his porch.
Atticus was right. One time he said you never really know a man until you stand in his shoes and walk around in them. Just standing on the Radley porch was enough. (ch 31)
The change in Scout’s attitude toward Boo demonstrates that she has learned empathy. She no longer sees him as a scary monster, but as a human being who has suffered. She cares about him, and understands that he cares about her.