Michael Gazzaniga in Discover:
We humans think we make all our decisions to act consciously and willfully. We all feel we are wonderfully unified, coherent mental machines and that our underlying brain structure must reflect this overpowering sense. It doesn’t. No command center keeps all other brain systems hopping to the instructions of a five-star general. The brain has millions of local processors making important decisions. There is no one boss in the brain. You are certainly not the boss of your brain. Have you ever succeeded in telling your brain to shut up already and go to sleep? Even though we know that the organization of the brain is made up of a gazillion decision centers, that neural activities going on at one level of organization are inexplicable at another level, and that there seems to be no boss, our conviction that we have a “self” making all the decisions is not dampened. It is a powerful illusion that is almost impossible to shake. In fact, there is little or no reason to shake it, for it has served us well as a species. There is, however, a reason to try to understand how it all comes about. If we understand why we feel in charge, we will understand why and how we make errors of thought and perception.
When I was a kid, I spent a lot of time in the desert of Southern California—out in the desert scrub and dry bunchgrass, surrounded by purple mountains, creosote bush, coyotes, and rattlesnakes. The reason I am still here today is because I have nonconscious processes that were honed by evolution. I jumped out of the way of many a rattlesnake, but that is not all. I also jumped out of the way of grass that rustled in the wind. I jumped, that is, before I was consciously aware that it was the wind that rustled the grass, rather than a rattler. If I had had only my conscious processes to depend on, I probably would have jumped less but been bitten on more than one occasion.
Conscious processes are slow, as are conscious decisions.
More here.
