What does Pip's experience with the "avenging phantom" tell you about his character & how is London affecting him?

The master-apprentice archetype is seen in a number of different relationships through Great Expectations, sometimes demonstrating the positive nature of the relationships, sometimes demonstrating the negative. The Miss Havisham/Estella master-apprentice relationship is decidedly negative. Miss Havisham raised Estella not as an individual, but as an extension of herself to fulfill that which she had not in her own life (not to find love, however, but to revenge love). In contrast, Pip was an apprentice to Joe, but Joe raised him out of generosity and love as opposed to any selfish reasons. Other master/apprentice relationships -- Mr. Trabb and his boy, Pip's own "Avenger" servant boy -- are more of a comment on the abusive treatment of children in Victorian times.