How is Nick's attitude toward Gatsby ambivalent even at the moment wen he says goodbye to him?
Toward the end of chapter 7, Nick is leaving Daisy and Tom's home after a turbulent day and is surprised to hear Gatsby call his name from behind a bush. Nick initially mentions that he hated Gatsby at that moment but listens as Gatsby explains to him that Daisy was driving. Gatsby then tells Nick that he is watching over the house to make sure Tom does not assault Daisy. When Nick looks into the window of the home, he sees Tom and Daisy casually sitting across from one another with no expression of malice. Nick mentions,
There was an unmistakable air of natural intimacy about the picture, and anybody would have said that they were conspiring together (Fitzgerald, 83).
Nick realizes that Tom has no intention of harming Daisy and that she has no intention of leaving her husband for Gatsby. When Nick tells Gatsby that he should go home and get some rest, Gatsby dismisses his suggestion and tells Nick that he will wait all night. Nick walks away feeling ambivalent and leaves Gatsby to continue his sacred "vigil" for the rest of the night.
Nick's feelings of ambivalence stem from his emotions toward Gatsby as well his understanding of Daisy and Tom's situation. There are aspects of Gatsby's character and behavior that upset and disgust Nick, but he cannot help sympathizing with the man. Nick understands that Gatsby is a dreamer who is attempting to gain the unattainable, and he is surrounded by superficial, selfish individuals. While Nick wishes Gatsby would give up on his dream, he does not have the desire or willpower to argue with Jay. Instead of attempting to reason with Gatsby, Nick leaves Jay to watch over the house, knowing that nothing will interfere with Tom and Daisy's marriage.
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At this point in the novel, Nick feels very strongly that Gatsbty is the best of the bunch he has asociated with. But he does not realize just how callous and self centered Tom, Daisy, Jordan, and even Meyer Wolfshiem are until after Gatsby's death. When the only two people who come to Gatdby's funeral are his father and "owl eyes", Nick realizes that Gatsby's love of Daisy was real, that he was real, even though his background wasn't. At this point his ambivalence for Gatsby is gone, and his feelings towards everyone else he has met in the east are sealed. This is why he goes back to the mid-west at the end of the novel.