Moby-Dick Questions Chs. 37-40: What has happened to the novel’s narrator

What has happened to the novel’s narrator and point-of-view?  Why is Ahab “damned in the midst of Paradise”?  (p. 183 [143])  Can Ahab help himself, or is something controlling him as much as he controls his crew?  How does Stubb see his predicament in Ch. 39, and what, if anything, does he have in common here with Starbuck?  In “Dusk,” what is Starbuck’s predicament and how does he see it?  How do you interpret the crew members interacting in ch. 40, and Pip’s prayer to God?