Russell Standish wrote:
>On Mon, Apr 11, 2005 at 10:41:53PM +1000, Stathis Papaioannou wrote:
> > It may be the case that quantum indeterminacy adds a random element
>which
> > contributes to our experience of free will, but you are dismissing the
> > other theoretical possibility, which is that our brains are vastly,
> > chaotically and perhaps even intractably complex, but nonetheless
> > completely deterministic machines. We would then still believe that we
>had
> > "free will" , even though in reality we are all blindly following a
> > predetermined script. How could we possibly know that this is not what
>is
> > in fact happening?
> >
> > --Stathis Papaioannou
> >
>
>I think this situation is essentially hypothetical. No machine is
>completely deterministic - computers are designed to be as
>deterministic as possible, but still suffer bit errors through
>chance. Human brains, however, strongly appear to be tuned to amplify
>noise generated at the synaptic level to effect system level. (Fractal
>structures in brainwave patterns, and the like).
I would like this important point clarified. There is a fundamental
difference between a classical, chaotic system and a truly random quantum
system. The classical system may look random and for practical purposes may
be taken as random, but if (a) we could measure the system's initial
conditions to an arbitrary level of precision, (b) we knew the equations
governing the behaviour of the system to an arbitrary level of precision,
and (c) we had an arbitrarily fast/precise computer (or an arbitrarily long
period in which to perform the calculation), we could calculate all future
states of the system. With even a relatively simple quantum system, however,
such as a single atom of a radioactive isotope, no amount of computing
power, precise measurement or knowledge of the laws of physics can help us
decide exactly when it will decay.
Now, it seems to me that in the brain both types of "random" event would
combine to give a very complex and unpredictable picture indeed: quantum
events at the atomic or subatomic scale would be amplified by chaotic
interactions at the classical scale. However, I have seen it stated that
quantum events would in fact not be significant at the scale of neuronal
processes. Which is correct? And does it really make much difference,
whether we are talking truly random or intractably pseudo-random?
>Now for the age-old corny question of whether free-will is an illusion
>or not. Mind is an emergent property - it is not to found among the
>neurons making up the brain, however it is a useful predictive
>model. This makes it emergent in just the same way as a glider is an
>emergent property in the Game of Life. Just as the mind is emergent,
>so is free-will, for the same reason. And just as you can argue (if
>you want to) that GoL gliders are an illusion, you can argues that
>mind and free-will is also an illusion - this does not preclude them
>as a useful modeling concept for the organism. My personal preference
>is to label these emergent concepts as real (when they're useful that
>is), but it is a matter of taste. As an aside, I always considered the
>high school explanation that centrifugal force was fictitious with
>suspicion.
My own view on free will: I feel as if I have it, but I know that in reality
my brain (hence my mind) is either following a deterministic script, or
(more likely) following a mostly deterministic script with a few random
numbers thrown in. This does not upset me, or make me change my behaviour,
any more than the knowledge that my brain is just a computer and my heart is
just a pump does.
--Stathis Papaioannou
_________________________________________________________________
Don’t just search. Find. Check out the new MSN Search!
http://search.msn.click-url.com/go/onm00200636ave/direct/01/
Received on Mon Apr 11 2005 - 23:29:17 PDT