From: emc@doe.carleton.ca (Eli Chiprout)
Subject: Re: The rise of consciousness
Keywords: brain,evolution,consciousness
Organization: Dept. of Electronics, Carleton University
Date: Tue, 1 Sep 1992 17:23:31 GMT

In <1992Sep1.160723.29164@cbnewsm.cb.att.com> mls@cbnewsm.cb.att.com (mike.siemon) writes:

>He [Edelman] argues, rather cogently,
>that our mental processes are NOT (in general) algorithmic (this
>is not to say that we can't *model* algorithmic processes in the
>system we actually employ).  

>This whole thing is *very* different from algorithmic computation
>a la Turing.  Edelman remarks, about this:

>	"The facile analogy with digital computers breaks down for
>	several reasons.  The tape read by a Turing machine is marked
>	unambiguously with symbols chosen from a finite set; in
>	contrast, the sensory signals available to nervous systems
>	are truly analog in nature and therefore are neither unam-
>	biguous nor finite in number.

>	[note: this is *not* in conflict with the purely engineering
>	result that *given* a particular range of analog signals, a
>	digital representation in finite numbers of bits can faithfully
>	preserve any predetermined level of information -- the point is
>	rather that we are not given any such engineering specification
>	for the operations of our nervous systems]

>					"Turing machines have by
>	definition a finite number of internal states, while there are
>	no apparent limits on the number of states the human nervous
>	system can assume (for example, by analog modulation of large
>	numbers of synaptic strengths in neuronal connections).  The
>	transitions of Turing machines between states are entirely
>	deterministic, while those of humans give ample appearance
>	of indeterminacy..."		[_BA, BF_, p. 225]

I find this very much more interesting.  The reason a system is indeterminate
however, is not because it is analog or digital, appearances aside.  
This can be shown
mathematically.  In fact digital processing carries information much
more accurately and over longer periods of time than can analog.  That
is why we are turning to digital phones, HDTV, cd's, DATs and soon
digital radio transmission.  That is why DNA is carried as digital
information.
Analog by itself, is not indeterminate.  The reason it is a poor carrier 
of information is that noise is introduced into more easily into analog 
systems (far less in digital because the signal is interpretted either 
as a 0 or as a 1).
But noise introduced into a system cannot be the cause of a sophisticated 
end product
such as consciousness.  If we go down far enough in size, all
the universe is digital -- quantum states.  Analog is an invention
of our minds, just as we see water as a smooth continous fluid.
However, once we come to this
level, the effects of quantum mechanics appear and THIS is what has
been argued causes indeterminacy and non-computability.  Discrete quantum
states describe the universe, but the states that a particle can be
in before it is measured, perceived, sensed, etc. is truly 
indeterminate.

An interesting case for non-computability based on 
quantum physics is given by Penfield in the Emperor's New Mind.

Analog computers preceeded digital ones because they are easier to
construct.  In fact if given the exact analog processing function(s)
going on in the brain, I can create an *analog* computer to do the same.
I could create a far more reliable digital computer but it would
operate extremely slowly in comparison to the analog model.
This however would not imply non-computability or indeterminacy.

This is what makes me curious about the problem.  Was consciousness
necessary for survival at a high enough level?  Is this why plants haven't
paralleled the evolution?  Would it be impossible for an unfeeling
automaton (digital or analog) to perform in the same way as a conscious
being? Is this why the brain might have to rely on the properties of
quantum mechanics to generate a higher order of creativity and problem
solving?  Perhaps the answer to "If I construct a machine complicated
enough to do what a human does, would it of necessity imply consciouness?"
is YES.

One other possibility that I have entertained (and I would appreciate
comments) is that each individual phenotype, is one among
all the possiblities in genetic space (which, given our number of genes,
is greater than all of the atoms in the known universe).  However, evolution
can only operate by progressing a small step from one genetic possibility to
another.  If large leaps are made in mutation or genetic variation then
the chances are that the result will not survive.  So there is a clear
genetic line (plane, hyperplane) of living possibilities that connect
the first life whith us.  Alongside these in genetic space are all of 
the possibilities that if developed phenotypically would not survive.
However, if we look
at the genetic space, is it possible that a phenotype that does exactly
what a conscious being does without the effect of consciousness, 
(an automaton with a far more complicated brain program) is
completely isolated in the genetic space.  That is, given the way life
was started, it would be impossible to find an evolutionary line from
here to there -- from unicelluar life to automatons.
Just a wild idea -- but allow me to indulge in some speculation.

>I am not urging that Edelman is "obviously" right and the positions he
>critiques wrong -- all sides are currently highly speculative and very
>controversial.  Merely that anyone with an interest in the matter should
>give Edelman a serious read, see what he is saying and consider the im-
>plications for the biology and psychology of mind.  Edelman is concerned
>(unlike some of the philosophers arguing in the area) with constructing
>testable, biologically well-founded theories and seeing them worked out.

I agree with that approach.  The only reason past philosophers needed
to use language instead of emprical results is that the latter was
simply not available.  I don't know however how consciousness will 
ever be fully empirical. I know that I am conscious, I assume that you are.
Is a machine conscious, or is it a clever simulation of a person
that has consciousness?

>Michael L. Siemon		
>mls@usl.com			
--
Eli Chiprout
Dept. of Electronics, Carleton University
Ottawa, Ontario, Canada
emc@doe.carleton.ca