From: erlebach@Informatik.TU-Muenchen.DE (Thomas Erlebach)
Subject: Brain / Computer
Originator: erlebach@hphalle8b.informatik.tu-muenchen.de
Organization: Technische Universitaet Muenchen, Germany
Date: Thu, 23 Jul 1992 07:16:22 GMT



When I was younger I thought that human thinking was completely
different from the way that machines (esp. computers) work.

Meanwhile, after reading books about psychology, learning lots
of stuff about computers and doing some thinking during boring
train rides, my opinion has changed. I see the human brain as
a kind of "biological computer", receiving input, processing
the information and providing output. And I don't think that there
is any kind of supernatural entity within the human body like a
soul or something like that.

Now let's make the following thought-experiment:
 - Assume that I would know everything about the human brain.
 - Let me have a computer with enough memory and being fast enough
   to simulate a model of the human brain in realtime (i.e. the computer
   doesn't work slower than the human brain).
 - Now assume I had written a program for this computer which performs
   this simulation.
 - Finally let me be able to get all data about a certain human brain,
   for example my own, feed this data into my computer and start the
   program.

So far, so good. What will happen ? What is the difference between
what goes on in my brain and what goes on in the computer-simulated
brain ? Is there any real difference ?

One point is that the simulated brain would work deterministically.
Given the state of the simulated brain at any certain moment, it
would be possible to predict what that brain is thinking 10 years
from then.

Of course we could add some sensoric input devices to the computer,
let's say two eye-like devices, two ear-like devices and so on.
(This should be possible in some years or decades or whatever, it
is just a question of technical progresss.)
Then let's add some output devices like an audio device for speech
and some robot-hands for manipulation of the computer's environment.
Finally let's put that whole machine into a mobile, self-supporting
unit. (I will refer to this machine as my "clone" in the following.)

Then the computer-brain would not be deterministic anymore. O.K.,
it would still react to a certain input in one (predictable) way.
But since the input is not predictable (e.g. nobody can tell the
weather 5 years from now, not due to lack of technical capabilities,
but due to the nature of things - at least this is the way I understand
some of the theories, e.g. quantum mechanics), it is not predictable
what the computer-brain will think 5 years from now.

Now some questions that arise from the above:

   1. What is the difference between my clone and myself, except
      from the way we are built ?
   2. Does the clone have "feelings", or something like "self-
      consciousness" ?
   3. Could anyone talking on the phone to either of us tell,
      whether he is talking to my clone or to myself ?
   4. If the clone has self-consciousness, from what moment on
      does he have it ? If it is from the moment when I start
      the program, does self-consciousness come into existence
      from one second to the other, whenever a kind of intelligent
      brain starts to work ?

I'm aware that this article would fit a philosophy group rather
well, too, but I hope that there are some t.o.-guys out there who
are interested in this and come up with some ideas, thoughts,
comments, criticism or whatever !

                        Cheers,

                             Tom
--
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                   erlebach@informatik.tu-muenchen.de

("Wayne's World"-quotes removed from my .sig due to lack of humor of
certain members of the t.o.-audience)

"Is the end of the world a-coming? Is that the Devil they hear humming?
Are those doomsday bells a-ringing? Is that the Devil they hear singing?
Or are their dark fears exaggerated? Are these doom-criers addlepated?
           Those who fear the coming of all Hells
           are those who should be feared themselves."
                                           - The Book of Counted Sorrows
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Xref: sparky talk.origins:8897 sci.astro:8463