by Douglas R. Hofstadter
Basic Books, 2007

To get into a properly loopy mind-set for Douglas R. Hofstadter's new book on consciousness, I plugged a Webcam into my desktop computer and pointed it at the screen. In the first instant, an image of the screen appeared on the screen and then the screen inside the screen. Cycling round and round, the video signal rapidly gave rise to a long corridor leading toward a patch of shimmering blue, beckoning like the light at the end of death's tunnel.

Giving the camera a twist, I watched as the regress of rectangles took on a spiraling shape spinning fibonaccily deeper into nowhere. Somewhere along the way a spot of red--a glint of sunlight, I later realized--became caught in the swirl, which slowly congealed into a planet of red continents and blue seas. Zooming in closer, I explored a surface that was erupting with yellow, orange and green volcanoes. Like Homer Simpson putting a fork inside the microwave, I feared for a moment that I had ruptured the very fabric of space and time.

In I Am a Strange Loop, Hofstadter, a cognitive and computer scientist at Indiana University, describes a more elaborate experiment with video feedback that he did many years ago at Stanford University. By that time he had become obsessed with the paradoxical nature of Gödel's theorem, with its formulas that speak of themselves. Over the years this and other loopiness--Escher's drawings of hands drawing hands, Bach's involuted fugues--were added to the stew, along with the conviction that all of this had something to do with consciousness. What finally emerged, in 1979, was Gödel, Escher, Bach: An Eternal Golden Braid, one of the most captivating books I have ever read.

I still remember standing in the aisle of a bookstore in Washington, D.C., where I had just finished graduate school, devouring the pages. GEB, as the author calls it, is not so much a "read" as an experience, a total immersion into Hofstadter's mind. It is a great place to be, and for those without time for the scenic route, I Am a Strange Loop pulls out the big themes and develops them into a more focused picture of consciousness.

Think of your eyes as that video camera, but with a significant upgrade: a mechanism, the brain, that not only registers images but abstracts them, arranging and constantly rearranging the data into mental structures--symbols, Hofstadter calls them--that stand as proxies for the exterior world. Along with your models of things and places are symbols for each of your friends, family members and colleagues, some so rich that the people almost live in your head.

Among this library of simulations there is naturally one of yourself, and that is where the strangeness begins.
"You make decisions, take actions, affect the world, receive feedback from the world, incorporate it into yourself, then the updated 'you' makes more decisions, and so forth, round and round," Hofstadter writes. What blossoms from the Gödelian vortex--this symbol system with the power to represent itself--is the "anatomically invisible, terribly murky thing called I." A self, or, to use the name he favors, a soul.

It need know nothing of neurons. Sealed off from the biological substrate, the actors in the internal drama are not things like "serotonin" or "synapse" or even "cerebrum," "hippocampus" or "cerebellum" but abstractions with names like "love," "jealousy," "hope" and "regret."

And that is what leads to the grand illusion. "In the soft, ethereal, neurology-free world of these players," the author writes, "the typical human brain perceives its very own 'I' as a pusher and a mover, never entertaining for a moment the idea that its star player might merely be a useful shorthand standing for a myriad infinitesimal entities and the invisible chemical transactions taking place among them."

Thinking of souls this way makes me feel better about the fly I just swatted. What?ever repertoire of symbols it may have possessed was surely too constricted for Gödelian self-representation to arise. The same would probably go for an amphibian or a fish or, for that matter, a human ovum that had just been fertilized by a sperm. But somewhere along the line--maybe with parakeets or cats--it becomes harder to deny the glint of some kind of "who" inside.

Souls, as Hofstadter puts it, come in "different sizes." In a whimsical moment, he even suggests that soulness might be measured--in units called "hun?e?kers," after an American music critic, James Huneker, who once wrote of a certain Chopin étude that "small-souled men" should not attempt it. The scale might start with a mosquito, with a tiny fraction of a huneker, ascending to 100 for an average human and upward to maybe 200 for Mahatma Gandhi.

Hofstadter's fans may find some of this familiar, but I Am a Strange Loop is much more than the condensed version of Gödel, Escher, Bach. In the 28 years since that book appeared, Hofstadter has lived with these ideas, working out their implications. From being a semivegetarian (fish and chicken were okay), he became, just recently, a strict one. Most significantly, in this time he learned what happens when another soul becomes entwined with your own. Her name was Carol, and as they became absorbed one into the other, consciousness spilling beyond its containers, he sometimes thought of them as "one individual with two bodies," sharing "exactly the same dreads and dreams and hopes and fears."

Then, when she was not yet 43, Carol died without warning from a brain tumor. Even though I knew that was coming, it did not diminish the blow. It is heart-wrenching to read how the author has tried to come to grips with her death, agonizing over how much "Carolness" and even "Carol-consciousness"--how much of her "interiority"--still lives in his brain and in those of the others who knew her.

Consciousness is a pattern. The substrate is not supposed to matter. And yet it does. I finished the book with a sense of the desperation that must come from losing, in body if not in spirit, one half of a 400-huneker soul.