The books that have had the greatest impact on my life are not the ones that entertained me the most—rather, they’re the ones I’ve had to endure. Ulysses wasn’t a “good read”—it was a project, a mission, a brief military stint undertaken by a strong-willed, idealistic youth. It was a labor to carry, it required innumerable accoutrements to be read (not just the two other texts but also a notebook and a pen, a highlighter, slips of scrap paper to mark particular pages). Even the page design was more an opponent than a partner: There were line numbers on each page. Line numbers! This book wasn’t kidding around. Reading it, you felt you were staring down the business end of Literature.

But to arrive at the end of a book like that—to complete the project of reading it—there is for me no greater satisfaction. Wracked, enlightened, tortured, exhausted, bettered, you come out the other side of a book like Ulysses feeling as though you’ve had an experience, as though you have actually, actively read. And there are, for those of us who enjoy such literature of endurance, many authors who write books like bricks you could use to build a sound shelter for the three little pigs: William Gaddis, John Barth, Doris Lessing, Thomas Pynchon, Neal Stephenson, David Foster Wallace (to mention just a few of the most recent examples). Granted, there are some big books that make you feel, as you close them, that they haven’t quite been worth the effort. For me, that’s the risk that makes the expedition all the more thrilling.

It’s possible that books are like relationships. Some people may be quite happy hopping from one book to the next, looking for easy reads in the same way you might troll the bars for easy lays. There are thousands of completely forgettable books that will amuse you for an evening or two; they seduce you with their market-tested cover art, their comfortable length (not to overwhelm commitment-phobes), even the unabashedly lewd pick-up lines that open their narratives, the lines referred to in writing workshops as “hooks”: The summer my dog died, I learned how to stop time.

I once had a relationship with William H. Gass’s The Tunnel. It was a difficult couple of months. We didn’t get along—even though on the surface it seemed we would be a perfect couple. It was certainly no Ulysses. But I stuck with it to the very end, searching for any glimmer of connection or love, so sure was I that there must be one. At the very last, however, we parted quietly, with little fanfare, a bit embarrassed at our failure to make it work.

Do I wish that book were easier to read?

No. I admire its depths, even though I was not the one meant to plumb them.

Do I wish that book were shorter?

No. I respect a book that respects itself—a book that is not ashamed of declaring itself in bold and profuse terms.

Do I regret having spent time reading it?

Not at all. What I wanted was not entertainment but an experience—and I got that experience, and it has stayed with me. I feel that The Tunnel and I accomplished something, and I am reminded of that accomplishment whenever I see the book resting, still admired and enduring, on my bookshelf.