"Let Me Read"
In a flashback scene, we get to see what married life was like for Leonard:
LEONARD: How can you read that again?
HIS WIFE: It's good.
LEONARD: You've read it, like, a thousand times.
HIS WIFE: I enjoy it.
LEONARD: I thought the pleasure of a book was in wanting to know what happens next.
Come on, Leonard. Stop being such a jerk. Some people just like reading their favorite books (cough*Harry Potter fans*cough) again and again, or watching entire seasons of Friends on repeat until they're literally quoting obscure Mr. Zelner lines in their sleep.
Leonard's nameless wife's reasons for reading her book so much she's worn the cover off (which conveniently doubles as an effective way of obscuring the books identity) are simple: it's good and she enjoys it. What's interesting is Leonard's reaction. He thinks that a novel's novelty is its primary source of enjoyment.
There's nothing inherently ironic about this comment and his later condition (which, in fact, seems more appropriate because Leonard gets to experience everything like it's the first time.
The irony comes from our experience as viewers. We don't get to wonder what happens next; we start from the end and so we already know. But just because the story works its way backwards through time doesn't mean we don't enjoy it. We still want to know what happens next… it just happens that next is first.
Okay, so what about the book itself? Well, if we look closely at the first page, we can read the words that clue us in on the books identity, Claudius the God and his Wife Messalina, the sequel to Robert Graves famous historical fiction I, Claudius. We're not going to go into too much detail, but the books follow the life of a once-emperor of Rome, Claudius, and his rise to and fall from power.
Claudius, in the first book, was looked down upon by his family and his peers. He had a bit of a stammering problem and some other quirks that made people think he wasn't playing with a full deck. So then, how does he become the emperor?
Well, the advantage of being thought of as an idiot is that you're not perceived to be threatening. While Claudius' relatives were taken out to protect or usurp the throne, Claudius got to watch it all from the safety of his home until he was suddenly first in line. As an emperor, Claudius expanded Rome and improved the quality of life for its citizens. He was actually a very intelligent man… until his super-manipulative wife screwed him over.
Leonard is in the same boat as our man Claudius. Teddy and Natalie are his Messalinas and society as a whole is like the Romans competing for the throne. Society merely views Leonard as incompetent and benign, while the Teddy and Natalie try to use his condition to get what they want out of him.
But Leonard isn't someone to be trifled with and (spoiler alert!) just like Messalina gets executed, Teddy realizes too late that he shouldn't have been messing with Lenny.