The main ideas in a text are called themes. In A Christmas Carol these include Christmas, redemption and social injustice. Dickens also deals with the themes of family and forgiveness.
Social injustice was explored in The Christmas Carol because Scrooge was never a social man, he never really talked, and if he did, it was yelling. When all three of the ghosts took him out, he realized how bad of a man he was.
