from the You/Thou chapter of Dan Beachy-Quick’s A Whaler’s Dictionary:
“But Moby-Dick is not a selfish book. Ishmael understands Ahab in the way he does, hears conversations no one can hear, sees Ahab when the captain is locked in his cabin, thinks Ahab’s thoughts as Ahab thinks them, because Ishmael’s quest and Ahab’s quest are the same. They occur simultaneously, in parallel direction, but at different levels. Ishmael stays above the waves, and loses the whales when they dive down; Ahab dives down with the whale. Ishmael tells our You of what happened aboard and to the Pequod. Ahab tells nobody nothing. Ahab is chasing his Thou.”

Don’t have your copy of A Whaler’s Dictionary yet? (You obviously need one.)