From: swf@teradata.com (Stanley Friesen)
Newsgroups: comp.ai.philosophy
Subject: Re: Brain and Mind (was: Logic and God)
Date: 13 Oct 92 21:06:11 GMT
Reply-To: swf@tdat.teradata.com (Stanley Friesen)
Organization: NCR Teradata Database Business Unit

In article <1992Oct8.211640.24394@meteor.wisc.edu> tobis@meteor.wisc.edu (Michael Tobis) writes:
|In article <1222@tdat.teradata.COM> swf@tdat.teradata.com (Stanley Friesen) writes:
|
|>True, until we have some characterization of what constitutes consciousness
|>in the human brain, we cannot precisely formulate what is necessary for
|>a process to be conscious.
|
|>However, the fact that the brain, performing physico-chemical operations,
|>can achieve it indicates that at least *one* process achieves consciousness.
|
|Well, it indicates that there is a process, but it indicates nothing about
|whether that process can be properly described as algorithmic. Your -chemical
|caveat seems designed to include Searle on your side here, which is fair
|but I would note that it also indicates that the process isn't as fully
|explained as you seem to imply.

Perhaps, i am certainly willing to cconsider alternatieves.

However, i have yet to see any reason to suppose that physico-chemical
processes are intrinsically any different than the electro-physical ones
that a computer uses.

|>But you *are* making 'extravagant' claims about consciousness.
|
|I don't make extravagant claims about it. Consciousness exists. That is
|extravagance enough. To claim that you have "explained" it is dubious, though,
|while merely to claim that it exists hardly is.

I do *not* claim to have explained consciousness.  I merely claim that noone
has yet demonstrated the existance of any phenomena that are not physical
in nature in the brain.

Thus, I consider even *suggesting* dualism at this point to be unwarrented.

Dualism is only admissible if *all* other explanations are eliminated.

|>What is subjectivity other than some form of recursive self-modelling?
|
|I see no meaningful content in that question, since a model is not a model
|without a consciousness to interpret it.

On what *objective* grounds do you base this conclusion?
What repeatable, generally available observations are there that rule
out operational interpretation?

What aspects of human behavior are inconsistant with this hypothesis?

Or, to put it another way, what is this 'consciousness' that interprets
the model, and how does it do so?  What observable consequences are there
to this 'consciousness'. (Mere interpretation of models is insufficient
evidence in itself, since the question at hand is whether such interpretation
requires something other than data processing).

|>Analogy with nuerons, for which the same arguments acan be made.
|>No single neuron can be conscious, only a properly designed system composed
|>of many interacting neurons can be so.
|
|Well Searle, and apparently Penrose, think there are physical characteristics
|of the brain that are not representable algorithmically or at least
|not functionally identical with their algorithmic representation.There is much
|room for doubt in your hypothesis that the essential feature of the neurons
|is their algorithmic nature.

Yep, they do.  They also know almost nothing about neurology.  The biological
section at the end of Penrose's book was so abysmal I could not even finish
reading it.

So far everthing we know about how a neurons interacts to produce 'thought'
is consistant with them being purely mechanistic processing elements.

|On the other side, we have a phenomenon of
|subjective existence that is not obviously reducible to physical processes.

Oh?  Why should I trust intuition and self-referential analysis?
Most classical paradoxes are derived from self-reference.

Again, what objective evidence do you have that the phenomenon called
'subjective' is anything other than an artifact of self-modeling?

|I can claim that a starfish has pentagonal symmetry, even though the
|cells of the starfish do not have that property. However, I can define
|that property in terms of the parts. In any other case where a property of
|a whole "emerges" from the relationship among the parts, I can, at least
|in principle, provide a formal definition of the property in terms of the
|relationships among the parts. To claim that the situation regarding
|mind and brain is comparable misses the point entirely. Consciousness
|is not defineable in terms of the relationship among the parts in any
|obvious or even obviously plausible way. The gap between subjective 
|experience and physiological facts is not one that has been bridged by
|defining one in terms of the other. 

Then how is it to be done?  Without bringing in non-scientific stuff
like dualism I see few other alternatives.

Just because we have not yet formulated a definition of consciousness in
terms of the interaction of its parts that satisfies *you* does not mean
it is a maeaningless quest, or that it is impossible.

|>You seem to be a bit behind in neurobiology.  A great many components of
|>brain function are understood now, more than most people realize.
|
|I think I know about as much about it as the average scientist who is not in 
|AI, psychology, or the life sciences.

True, but that is not enough for the subject at hand.

Even *I* am too far behind to make adequate mind models based on current
knowledge.  Only someone truly up with the cutting edge of neurology is
in a position to say much about the relationship between neural activity
and mind.

|>Furthermore, there is tremendous evidence, from deficit studies, simulated
|>neural network studies, PET scans, neural connectivity studies, and others
|>that most, or all, sorts of capabilities shown by humans can be, and are,
|>generated by the activities of the components of the brain (mostly neurons).
|
|I do not deny that the brain has something to do with it. I just deny
|that we know what that is, or even have anything resembling a hypothesis
|of what that might be.

How do you know this if you do not know the current state of neurology?
There have been a number of really astounding breakthroughs in this field
in the last five years.  The status of the mind/matter interface is quite
different now than it was five years ago.

|>Thus, the idea that there is more there *does* become unscientific, in that
|>it lacks any supporting data, and makes no testable claims.
|
|Well, the supporting datum is my experience, admittedly a lone observation
|but a pretty robust one. I can't really demonstrate this datum to you,
|but I can hope you have a similar observation available to yourself.
|This phenomenon is not defineable in terms of or reducible to any known
|physical processes.

Why not?  I see nothing in the subjective experience that requires anything
other than known physical processes.
-- 
sarima@teradata.com			(formerly tdatirv!sarima)
  or
Stanley.Friesen@ElSegundoCA.ncr.com