I read that you consider yourself an agnostic. So how did you come to write about a Carmelite nun struggling with her relationship to God?

My initial interest in the story came after reading an article about temporal lobe epilepsy. The fact that the symptoms of the disorder were a sudden intensification of interest in religious, philosophical, or cosmic matters fascinated me. I thought, "What if someone who had already dedicated her life to a search for God were to develop the symptoms of this disorder in midlife? Wouldn't she interpret those experiences as confirmation of her spiritual path?"

But if she were then told that a physiological abnormality might explain the experiences she's having, wouldn't it be a great struggle for her? Would it mean that her experiences were not real? So my initial interest was in the question of how do you decide whether your subjective experiences are valid, especially if they are triggered by something physiological.

Say more about that.

Let's say you have a terrible fever and you start having negative thoughts about life; you feel that everything is hopeless. When you come out it, you say it's a good thing I didn't listen to myself, because I was not thinking clearly.

But what if during the fever you have really positive feelings? When you come out of it, do you then dismiss them as you did the negative feelings, or do you say, well maybe they were an intensification of the wisdom I already had.

I was interested in that question. But the more I got into the story, the more difficulties I had writing it, and the harder time I had making the main character, the Carmelite nun, come to life. It gradually occurred to me that my problem stemmed from the fact I didn't have much of a personal connection to the character. I had never had a religious experience, and I had never struggled with the question of religious faith.

Then it occurred to me to ask myself: If this character is someone who has dedicated her life to a search for God, what have I dedicated my life to? I thought about it, and the answer came to me: I've dedicated my life to art, to trying to find the good through art. But, if I'm such a rational person--as opposed to a person who lives by faith--what rational objective reasoning do I have that justifies searching for the good through art? I realized that I don't have a reason. I take it entirely as a matter of faith that good exists and that art is worthwhile. I realized that my own life is as much based on faith as any Carmelite nun. It never occurred to me to think that way before. Once I did, then the character's struggles made sense. And I cared about the character.

I thought what you were going to say was that the idea came to you because of your martial arts background. I imagine that there's a regularity of practice and discipline--in fact, a kind of devotion--that might have some parallels to spiritual life.

I think that is certainly true. It's also true of my cello practice--I play the Bach suites every day. Since I was seven years old, I have--with only one break after college--continuously played the cello. For me, the Bach suites are a kind of breviary; they are like the cycle of Psalms that the nuns recite.

Each time I play through the cycle, I feel that I learn something; I feel that they are Psalms without words. With daily practice, you go through stretches where you feel you have nothing to bring to them; you feel dry, you feel like you have exhausted your own ability to bring something of yourself to the music. But then after a long plateau, there will be a leap, a new insight, and they suddenly seem fresh again.

There is a contemplative feel to the book which has a lot to do with the short prayers you place throughout. How did you come to do that?

I decided to do that after I met a Carmelite nun who was very, very interested and enthusiastic about the book. She was willing to be my guide into her world and to help me understand, as best I could, what her life was like. She suggested that I read through the Liturgy of the Hours at the same time the nuns do during the day, and to do that for a year.

For a year, I made it part of my life.

I followed the breviary instructions and read through the same text that they were reading. They chant it; I read it silently. But it made me realize that this practice of going back to the Psalms sets up a resonance. I found myself thinking of phrases from these prayers at odd hours of the day because they were ringing in my mind. Returning to the Psalms several times a day keeps the resonance going.