How does Mrs. Dubose show true courage as Atticus said? What examples in part 1 show the theme of avoiding cruelty toward others?

Mrs. Dubose knew that she was dying, but chose to fight to die free of her addiction to morphine. Although Mrs. Dubose could have made the decision to die a relatively peaceful death free of pain, she chose to die free of the control of addiction. She showed true courage, which is, according to Atticus, "when you know you're licked before you begin but you begin anyway and you see it through no matter what"; Atticus goes on to tell Jem that "you rarely win, but sometimes you do." Mrs. Dubose knew that she would not live much beyond her battle, and that she would likely die a less comfortable death than was possible, but she was true to her convictions and died with peace of mind.