A few examples of this are the characters. Hal, who looks at maps all day in the hospital is represented by the Navigator. Carlyle, who is one of Caden's good friends and is not mentally ill is represented by Carlyle on the ship, who knows mysterious things about the captain and the ship. Finally, Callie, who is the love interest in the book, is represented by Calliope, who is the ship's figurehead. Callie and Calliope have a lot of resemblance in the things that they say. For example, here is what they both said when Caden first met them at different times.
"There are things going on behind my back, aren't there?"
"Yes."
"Do they speak ill of me? The captain and his pet? The crewmen and their demons that hide in crevices?"
"They don't speak of you at all, at least not since I have arrived."
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"The others talk about me, don't they? I know they do. They say terrible things behind my back. All of them."
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