Scout and her father have many important conversations, but one very important one happens in chapter three:
He tells Scout, 'You never really understand a person until you walk around in their skin,' indicating to Scout to consider things from the other person's point of view.
Again, Scout and her father are having an important conversation as to why Atticus is defending Tom Robinson. Atticus states that he would not respect himself if he did not do what he thinks is right by defending Tom:
'If you shouldn't be defendin' him, then why are you doin' it?'
'For a number of reasons,' said Atticus. 'The main one is, if I didn't I couldn't hold up my head in town, I couldn't represent this county in the legislature, I couldn't even tell you or Jem not to do something again.' […]
'Atticus, are we going to win it?'
'Simply because we were licked a hundred years before we started is no reason for us not to try to win,' Atticus said. (Chapter 9)
Atticus is being realistic. He thinks they are going to lose, but the truth has to begin somewhere. Perhaps, people will begin changing knowing that Atticus is defending Tom.
When Scout is speaking with her father, she states what other folks are thinking:
'Atticus, you must be wrong....'
'Well, most folks seem to think they're right and you're wrong....'
'They're certainly entitled to think that, and they're entitled to full respect for their opinions,' said Atticus, 'but before I can live with other folks I've got to live with myself. The one thing that doesn't abide by majority rule is a person's conscience.' (Chapter 11)
This conversation is quite important in that Scout is really questioning whether or not Atticus is wrong in defending Tom Robinson. Based on what others think, Atticus is wrong. But even in their own thoughts, Atticus states that they are entitled to full respect for their opinions.
Another instance when Atticus is teaching his children respect occurs in chapter eleven. Even when Mrs. Dubose is rude, Atticus says she has to be shown respect:
'Son, I have no doubt that you've been annoyed by your contemporaries about me lawing for niggers, as you say, but to do something like this to a sick old lady is inexcusable. I strongly advise you to go down and have a talk with Mrs. Dubose,' said Atticus. 'Come straight home afterward.' (Chapter 11)
Atticus insists that his children treat everyone with respect, even when others are rude.
Atticus realizes he is fighting a losing battle, but he is determined to tell the truth:
'Link, that boy might go to the chair, but he's not going till the truth's told.' Atticus's voice was even. 'And you know what the truth is.' (Chapter 15)
Atticus did his best to defend Tom Robinson. Even though he lost the trial, he won a war in that he did the right thing, no matter how many people were offended by it.