I have just begun reading a fascinating book, Second Nature: Brain Science and Human Knowledge by the Nobel Laureate, Gerald Edelman. I wish that this book had been around thirty years ago when I was stuck in the philosophical quagmire known as “analytic philosophy of mind.” This would have been my Bible! As it was, I could only struggle on my own, a single undergraduate, towards a point of view that was pretty much rejected as irrelevant by the philosophic “giants” by whom I was being taught.
Edelman makes the important and emphatic point that the brain is not a computer. He is dismissive of artificial intelligence as it is practiced today, although he expects, eventually, that an artificial mind will be created…it just won’t be a machine! The mechanistic metaphor is so deeply embedded in our intellectual culture that this notion seems far fetched, wacky, at first if you are the type of person who has been seriously contemplating the riddles of consciousness. For many, the computer has seemed to be the best, if not the perfect model on which to draw for explanations of mentality.
In his book, right up front, Edelman makes the point that the brain, which is the primary seat of mind, is nothing like any machine. It is not like any machine humans have ever have, or would ever think of designing. To call it a machine, however poetically, is to do violence to the facts of biology and neuroscience. Why?
A computing machine runs on a clock – tick – tock – tick…each click of the microprocessor (that’s what all those GHtz specifications in the sales sheets are about, the clock speed of the central processor) sets up the machine to do another teeny part of the programmed algorithm…in order…in sequence. The brain has no such clock. It is massively parallel and massively redundant. The same result can be reached through an infinitude of computing paths. Not only that, the results of the previous activity-state, change the current state and future results. (When we train, we force a groove as it were, into our brain so that something, mental activity, physical motion of a certain sort, becomes easier, unconscious…) No machine behaves this way or is even conceived of to behave this way.
So, the machine metaphor is inadequate, and unecessary, for explanations of mind and consciousness. What a relief!