Nathaniel Philbrick was on the show this week to talk about one of the greatest American novels, Herman Melville's Moby-Dick.

"I think of all the classics, Moby-Dick is the most reluctantly read. It is so long, it is digressive. Just when you think you're figuring out where it's going, Melville throws in a short chapter about something completely different. And it's a real challenge," Philbrick explains. "It's a book I find, later in life, when you have some life experiences to bring to the book, you begin to see it in a different light."

The digressions are about things like the whiteness of a whale, and ambergris (which is whale vomit), and chowder—Melville even includes a recipe for chowder!

Asked why the novel's first line—"Call me Ishmael"—is so famous, Philbrick replied: "Just think about it. It's like, hey, call me Ishmael! It's very familiar, but Ishmael? Who is this Ishmael? It's beguiling and yet mysterious and he does it with three words. It's really hard to beat."

Ishmael is one of the book's many Biblical references. In the Bible, Ishmael was kicked out of his family home and was forced to wander the desert, and in Moby-Dick, the character Ishmael is wandering the seas of the world. Philbrick says, "The sea is a wilderness. And the wilderness has great potential for adventure, but in the end is a heartless killer of humanity."

Philbrick calls Moby-Dick, written in 1851, a very American story: "It creates it's own language in a profound way. That is, it's almost an American language, that I think sort of transports the Bible, Milton, and Shakespeare into something that's very American."

It's also an unusual novel for its time—in both the way it's written and what it's about. "It's a book that's written for the future," Philbrick says. "There was a dark skepticism, a bleak skepticism in his soul, " he went on to add. "That spiritual, questing nature is all over the book."

Moby-Dick has a reputation of being long and difficult, which can intimidate readers, but it also contains a lot of humor and some unexpected jokes.

If you haven't read Melville's masterpiece about a man's vengeful, obsessive pursuit of an illusive white whale, maybe Philbrick's enthusiasm will convince you to try. Listen to the entire interview here.