I'm a complete slob when it comes to books — at least, to books that I own.

I use anything at hand to mark my page (a leaf, a rip of a newspaper, a Popsicle stick). Or I plunk my book facedown, with no concerns about the health of its spine.

And I mark pages. Oh, boy, do I mark pages.

Apparently, I got an early start at it. Cleaning out a bookshelf recently, I came across one of the picture dictionaries we had as kids. I had laid claim to it by writing my name in large, shaky letters across the top of the first 25 pages. In pen. (I also used the blank pages inside to practice my ABCs.)

When I was in college, I filled the Bible-thin pages of my expensive anthologies with hieroglyphics of highlighter (yellow) and cramped notes in ink.

I still have those books, but I can barely read Shelley's "Mutability" or Tennyson's "Ulysses" for all the underlines, exclamation points and indecipherable notes I scribbled in margins.

Ironically, when I gave up pricey new anthologies for cheap used paperbacks, I became a less obvious marker. I became a turner of page corners. A little fold for a nice phrase, a larger fold for a profound paragraph, a double fold for something transcendent.

My new method of marking wasn't out of deference to books. I was annoyed by blots left by the readers who had come before me. I studied their underlines and exclamation points and couldn't find a paragraph worth noting, not even a tidbit of wisdom.

Recently, I was at dinner at the house of friends who keep wonderfully stocked bookshelves. I started reading spines, skimming through the classics and the bestsellers until I came across one with an intriguing title, "The Elegance of the Hedgehog."

When I took it down, I noticed it looked like one of my books: corners turned down, ripped Post-it notes clinging to pages.

John and I had traded books before. We'd even had a one-off book club devoted to a book we'd both enjoyed. But I'd never borrowed a book of his that gave any evidence it had been read, let alone loved.

Reading "Hedgehog" was a treat. I loved the story of a seemingly dull Paris concierge who comes into her own. But reading this copy was even better: It was like I was reading my friend's mind, not just his book.

I looked forward to every dog-eared page because I could instantly identify which paragraph had moved him: It was the same paragraph I would have underlined. It was as if we were sitting side by side on the sofa reading, occasionally interrupting each to say, "Oh, you've gotta hear this."

Toward the end of the book, I came across a page that had its corner double-folded and was also marked by sliver of a Post-it. It even had a carefully worn thumbnail mark next to this magnificent phrase:

"When did I first experience the exquisite sense of surrender that is possible only with another person? The peace of mind one experiences on one's own, one's certainty of self in the serenity of solitude, are nothing in comparison to the release and openness and fluency one shares with another, in close companionship."

We think of reading as a solitary activity — one in which we might connect with the characters, with new worlds, with the author.

But I realized while reading this well-used copy of "The Elegance of the Hedgehog" that I hadn't been alone. I'd been in close companionship with my friend John.

By lending me his book, he helped me discover what I now understand: Reading can be an exquisite — and shared — sense of surrender.

Connie Nelson is the Star Tribune's senior editor for lifestyles.