Look at that: it's been a week and I still haven't read any of Moby Dick.
"It stands alongside James Joyce’s Ulysses and Laurence Sterne’s Tristram Shandy as a novel that appears bizarre to the point of being unreadable but proves to be infinitely open to interpretation and discovery" (http://www.sparknotes.com/lit/mobydick/context.html). It's funny because I always think that no one ever actually read Ulysses although 20th century book lists always place it at the top. That's another one that I gave up on during my first year at Western Illinois University for a really boring modern mythology class. (Although I did read the pretty neat Grendel by Gardner for that class.) If that quote starts off the Sparknotes on Moby Dick, it doesn't bode too well.
Several years ago, I did read a book that was a historical account of what Moby Dick is supposedly based on. In the Heart of the Sea: The Tragedy of the Whaleship Essex by Nathaniel Philbrick was a very enjoyable read (image courtesy of Amazon.com, where the book as of February 4, 2007, could be purchased for 60 cents used). The whaleship Essex went down from an actual whale attack off the western coast of South America about 10,000 miles from any land. The whale actually rammed the ship. Several men were stranded at places called Henderson Island and Pitcairn Island. Many men resorted to cannibalism in their life rafts due to the long voyage.
It was an amazing book. I loved it and still remember its vivid descriptions of what these men went through. It was an ultimate adventure.
So I could see Captain Ahab wanting revenge after such a whale attack.