Atticus is extremely intelligent. He reads constantly. He reads to his children. He proves his intelligence while defending Tom Robinson. He points out that the person who assaulted Mayella had to be left handed. Tom Robinson's left arm was crippled. He could not have assaulted Mayella.
Atticus is also a fair man. He represents Walter Cunningham for payment in firewood and hickory nuts. He is open minded. He shows no prejudices. Atticus has a black housekeeper who is as part of his family. Atticus is a good man and a great father.