How Brains Think: Evolving Intelligence, Then and Now. William H. Calvin. Basic Books.

How Brains Think: Evolving Intelligence, Then and Now Book Cover How Brains Think: Evolving Intelligence, Then and Now
William H. Calvin
Basic Books
September 5, 1996

If you’re good at finding the one right answer to life’s multiple-choice questions, you’re “smart.” But “intelligence” is what you need when contemplating the leftovers in the refrigerator, trying to figure out what might go with them; or if you’re trying to speak a sentence that you’ve never spoken before. As Jean Piaget used to say, intelligence is what you use when you don’t know what to do, when all the standard answers are inadequate.

Evolving something new “on-the-fly” involves a great deal of creative trial-and-error inside the brain, mostly in the last second before speaking aloud. Starting from themes as disjointed and unrealistic as those of a dream, you make something of quality out of the subconscious morass. How?

This book tries to fathom how our inner life evolves from one second to the next, as we steer ourselves from one topic to another, as we create and reject alternatives. It’s not just a little person inside the head doing all this, though it’s natural to assume that anything fancy requires an even fancier designer. Ever since Darwin, however, we’ve known that elegant things can also emerge (indeed, self-organize) from “simpler” beginnings.

And, says theoretical neurophysiologist William H. Calvin, the bootstrapping of new ideas works much like the immune response for the evolution of a new animal species – except that the brain can turn the darwinian crank a lot faster, on the timescale of thought and action. Few proposals achieve a perfect ten when judged against our memories, but we can subconsciously try out variations, using many brain regions. Eventually, as quality improves, we become conscious of our new invention.

Drawing on anthropology, evolutionary biology, linguistics, and the neurosciences, Calvin also considers how a more intelligent brain developed using slow biological improvements over the last few million years. Long ago, evolving jack-of-all-trades versatility was encouraged by abrupt climate changes. Now, evolving intelligence uses a nonbiological track: augmenting human intelligence and building intelligent machines. In his concluding chapter, Calvin cautions about arms races and intelligence. Just as the Red Queen explained to Alice in Wonderland, you might have to keep running to stay in the same place.

William H. Calvin is a theoretical neurophysiologist at the University of Washington in Seattle. He is the author of nine books, including The Cerebral Code, The River That Flows Uphill, and, with the neurosurgeon George A. Ojemann, Conversations with Neil’s Brain.