How Brains Think: Evolving Intelligence, Then and Now

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 needs 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 or the evolution of a new animal species - except that the brain can turn the Darwinian crank a lot faster, on the time scale 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 newinvention.

Drawing on anthropology, evolutionary biology, linguistics, and neurosciences, Calvin also considers how amore 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 non-biological track: Augmenting human intelligence and building intelligent machines. In his concluding chapter, Calvin cautions about arms races in intelligence. Just as the Red Queen explained in "Alice in Wonderland," you might have to keep running to stay in the same place.