Friday, February 26, 2010

Wiggling a finger

Do a little exercise for me. Stick out your arm in front of you. Now wiggle your index finger from side to side. Now bend it back and forth. Now wiggle your pinkie.

"Uh," you say, "what was that all about?"

Think for a minute about what just happened.

Photons from the screen of your computer entered your eyes. They formed images of little squiggles on your retinas and signals were sent to the brain. The brain interpreted the signals as instructions, and sent out electrochemical pulses that were routed specifically to your arm and hand. To muscles specified by the squiggles. That reacted in a certain way. All so fast it seemed instantaneous.

I dare say that for most of human history no one gave any of this a thought, because there was nothing to think about. It just happened. It was part of the self, the spooky inhabitant of the body that was like a -- well, like a spooky inhabitant of the body. It just happened.

Even now, when we know so much about the electrochemistry of neurons, we still don't think about it. Wiggling a finger is a "miracle" of an extraordinary magnitude that we take for granted.

In fact, the more you think about wiggling your finger, the more impossible it seems that all that processing and routing and reaction is just an electrochemical buzz that happens essentially instantaneously. Knowing a little bit about what is happening electrochemically doesn't explain away a mystery; it rubs our noses in mystery. What previously did not register on our consciousness now seems a thing of astonishing grandeur. The wiggling of a finger.

But mystery is not miracle.

Think a bit more about what happened. You clicked on a bookmark. Instantly this post appeared on the screen of your computer, no matter where you are in the world. Pulses of electricity flew through an international maze of routers and servers, packets of data flying hither and yon at almost the speed of light, retrieving something stored on a server even I don't know where, to be assembled on the screen of your computer by the circuitry within.

That vast web of interconnected computers that is the internet is astonishing, but there is nothing miraculous about it. What happens in your body when you wiggle your finger is a system of routers and servers of equal -- or greater -- complexity, and there is nothing miraculous about it.

Oh, I could carry on this theme forever. How did the "internet" that is your nervous system come into existence? It was somehow all programmed into your DNA as a four-letter code, which was expressed in interaction with the environment, assembling -- well, you. And that is the "miracle" of development from a fertilized egg -- which is, of course, another story.

And another behind that.

And another...