Nick's meeting with Wolfshiem leads him to believe that Gatsby might have acquired his money illegally. Wolfshiem is a notorious gangster who is rumored to have been involved in organized crime, and Nick is surprised that Gatsby is associated with him. Wolfshiem's presence in the novel suggests that Gatsby's wealth may be the result of illegal activities, such as bootlegging or gambling. While Nick does not have concrete proof that Gatsby's money is dirty, his association with Wolfshiem raises suspicions.
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