What do your books say?

In reading Sara Gran's excellent new novel Claire DeWitt and the City of the Dead, I began thinking of the clues people provide about themselves in their purchases and possessions. Some of them are obvious, the clothes one wears or the car one drives. Others can only be noted in the confines of a home - the music and art, even the food in the cabinet. Many of these clues we read and process subconsciously, part of what makes us functioning humans.

Clare DeWitt, in attempting to solve the Case of the Green Parrot, looks first for the clues we hide - those in the medicine cabinet, the safe, and under the bed - dismissing them as things the subject thinks are important. The real importance lies in those things we ignore the significance of. Of course, books are most telling to me, though you can't just limit yourself to the titles on the shelf. Those, of course, are what the subject thinks are important. Dig a little deeper and open those books, view the cracks in the spines, and the yellowing of the pages. Is that Nobel prize winner virtually untouched? Are there scribbles in the margins? Which page does the cookbook automatically fall open to? Which books are by the sofa or shoved under the bed? How are the books arranged on the shelf? Perhaps only a librarian would care or see the patterns there. Books have a lot to say, more than just the words on the page, if only we look for it. And browsing a bookshelf is a lot more acceptable behavior when visiting a person's house than rummaging in the medicine cabinet or the sock drawer.

When you are a heavy library user, you deprive your guests of this font of information about both your reading habits and your inner self. You, of course can check out your reading history in your ABC libraries account, though no one else can see it. However, most library users have their own book collections at home, so all is not lost. So, how much could an average person learn about you from your books? Even better, how much could a librarian learn about you?