Between chapters 1-39 (Volume One and Two), how has Mr. Pumblechook made an impact on Pip's life so far?
Pumblechook most likely annoyed Pip from the very beginning of his life. His sister Mrs. Joe always doted on "Uncle P" and went out of her way to entertain him during the holidays. Although he belonged to a higher class in society, it wasn't by much. While Pip was poor, Pumblechook was the stereotypical snob. Then as Pip came into money and his "great expectations," Pumblechook wanted nothing more than to be his best friend.
Pumblechook later tried to claim responsibility of Pip's good fortune. After all, he was the one who introduced Pip to Miss Havisham (who all believe is the true benefactor). So in Pip's life up until the end of Part 2 of the novel, Pumblechook is merely a snobby social climber who is in it for none other than himself all the way through the book. Pip tries very hard not to turn into such a character, but does fall a little short in certain aspects--in the way he treats others. The role of Pumblechook is to represent the negative aspects of a richer society--from people who don't deserve better treatment than anyone else. Pip then assumes a very similar role. He is not educated for anything--yet he spends like he's earned it all.