Subject: Re: Is uploading feasible?
From: lmk2
Date: 17 Dec 1993 19:04:30 GMT
WilsonR at LILHD.Logica.com (Richard Wilson) writes:
> > Who says that neural activity can "choose," and what is choosing?
>> I do and I agree with you: what is choosing?
>
It seems to me that in our intuitive definition of choosing requires
non-determinism. If a computer program is playing chess, is it choosing
which move to make next? If you would say yes, then we have a
deterministic system that can choose, so you can't really argue that the
brain is nondeterministic because it can choose. If you would say no,
then it seems to me that your reason for saying that it can't choose is
because you know that the system is deterministic, and that makes the
arguement that the brain is nondeterministic because it can choose
circular because you would be basing your statement that it can choose on
it being nondeterministic. Do you see what I am trying to get at? I
hate to argue word definitions though.
> >Looking at the brain as a machine, with input as the axons projecting
> >into the brain, and output as the axons projecting out of the brain,
if
>> Why exclude the neurons in the brain?
>
I would call those part of the machine. I would agree though, as other
people have pointed out, that it is hard to draw a line that defines what
is brain, and what is not, and it's not as simple as I was trying to make
it out to be.
> >you believe that the laws of physics are deterministic (ignoring
quantum
> >mechanics), then it seems that the brain must be deterministic. This
>> Ignoring QM: how can you do that?! Anyway, my argument is not dependent
> on QM: I'm not talking physics, I'm talking cybernetics.
>
Ok, let's ignore QM then...
> >seems to contradict our ideas of consciousness and free-will, but it
> >seems to me that you have invoke religous arguments for a soul to get
> >free will.
>> Not so and I don't. Traditionally, the scientific focus has been on
> linear systems. Even then we still have the show-stopper of the 3 (or
more)
> body problem. The activity in the brain is certainly non-linear and no
> one claims to have a theory to account for it.
>
However, no one would argue that the 3 body problem is
non-deterministic. We can write Newton's law for all 3 bodies, which
completely describes what would happen. We just don't have the
mathematical tools to write out equations for the positions of the 3
bodies over time. There are lots of chaotic systems that are described
by simple equations, and I would say that those are completely
deterministic, but very complex and hard to predict.
> > Of course, the brain has so many neurons, and there is so much going
on
> >in the brain with neuromodulators and other things we don't understand
> >very well, that there is no way that we could predict responses, but
it
> >seems to me that the brain is ultimately deterministic.
>> Possibly, but I don't think so and one example is that of choice, which
> I consider to be a real phenomenon in need of explanation.
In article <2esvru$phb at agate.berkeley.edu> , lmk2 at garnet.berkeley.edu
writes:
>>Brain processing does not obey all the laws of thermodynamics.
>It is an open system. Yes there are axons going in and out, but there
>is also blood flow going in and out, there is input going in and
>not coming out, and so forth. To think of it as a box, into which
>you put "stuff", and out of which pours "stuff", is much the same
>as thinking of the earth as a closed ecosystem, not affected by the
>varying relative position of it to the sun, meteors, and so forth.
>Lately lots of folks are fond of saying that quantum effects provide
>for free will, the reasoning of which escapes me. I don't think that
>you need to go to that level to find indeterminism.
>
I agree with you that I greatly over simplified things. Also, the
molecules that make up our brain are constantly changing, and some
molecules from that bagel I had for breakfast will ultimately make up
part of my brain. So, you're right, it's not a closed system. But, I
think that we could draw a much bigger box around the brain, like the
size of the universe, or whatever you would agree is a closed system, and
if you would agree that this is deterministic, then I would say that the
brain, as part of this system would be deterministic. I agree that
quantum mechanics would say that this system is not truly deterministic,
but I also agree with you that I don't see that this would provide free
will, but I think that you do have to go to that level to find
indeterminism.
alexandr at ncifcrf.gov (Jerry N. Alexandratos) writes:
> Dan: In re your arguement that the brain is deterministic, how can you
say
> it is so fixed? The sheer number of "input" and "output" neurons and
the type
> of input, processing, etc., practically guarantees a random input
leading to
> some probability of random output. In addition, we speak of a complex
system
> which is self-modifying; it learns, gets damaged (daily), repairs
damage, and
> constantly must process new stimuli. You speak of a brain as some sort
of
> static "neural net" computer model, not a living system.
I didn't mean to give that impression. See what I said above.
Have a good x-mas everyone.
Dan
(crevier at husc.harvard.edu)
