IUBio

why study neurology?

Nick Medford nick at hermit0.demon.co.uk
Wed Jan 16 20:18:37 EST 2002


In article <43525ce3.0201161337.3ff59923 at posting.google.com>, mat
<mats_trash at hotmail.com> writes
>> 
>> Right- an irreducible piece of knowledge or experience- as I have been
>> arguing. This doesn't mean it doesn't exist.
>> 
>Hang on don't try and conflate my ideas into yours! Just knowledge
>thanks, not experience :)

Not experience? Looking at a red box-file (as I am right now) and
perceiving its redness is not an experience? Is this what you are saying? 

>
>> 
>> Actually I disagree- on this point at least I am more pro-science than
>> you! I would suggest that the functions of the motor cortex for example
>> have been pretty well described with reference to their manifestations in
>> the outside world. Cognition and emotion are different matters.
>> 
>
>well I suppose we have homunculi mapped etc, but any description at a
>level below brain regions are at smallest cortical columns is beyond
>us. I suppose my test of any theory would be if we could make testable
>asserations on a neuronal/network level, and I don't think we can yet
>unfortunately.

Actually I have seen some very interesting neural network work on
epilepsy (from the Centre for Brain Dynamics in Sydney, I may be able
to dig out a ref if you are interested) where the network can be made to
"have a fit" by introducing disturbance at the appropriate point, but this
isn't my field and I don't feel familiar enough with the computational side
to discuss it in depth here.

>> 
>> Consider a motorbike- it's made up of various material components that
>> act together in a certain way. From the action of these components
>> emerges a property: motion. This motion in turn has various properties-
>> velocity, acceleration, deceleration etc. So various levels of property
>> emerge, *without* having to postulate any magic "motion stuff"  (cf
>> "mind stuff"). To say that the motion is in fact the same as the concerted
>> actions of the brakes, engine, fuel etc. doesn't seem like "common sense"
>> (to borrow your term) to me. It is derived from them but not the same as
>> them.  
>
>But there is one big problem with that line of argument.  Everything
>you describe as emergent is an objective property.  The motion of the
>bike only occurs relative to you (lets not get into physics here!). 
>Similarly, emergent properties are objective, someone has to look and
>'see' an emergent property, the system cannot do it itself.  

I don't see why this is a problem: leaving aside the question of does the
bike still move (or the tree still fall) if there is no-one to see it (let's not
even go there!), the stubborn fact remains that sitting here now, I can
experience redness, and I can register that I am having that experience.
So there isn't much point in claiming that the mind cannot "see" its own
emergent properties, our day-to-day experience stands as a flat
contradiction of that. Once again I am happy to acknowledge that this
argument is not scientific: but since I don't take the view that everything
real must be amenable to current scientific explanation, this doesn't
bother me. 

If I may just repost something I said earlier:

>>-Your reasoning seems to be: I can experience redness, but I can't
describe it, so therefore it must be the case that it doesn't really exist.
Whereas mine is-  I can experience redness, but I can't describe it, so I
am forced to conclude that there are limits to my powers of description -

Similarly the fact that I am able to register conscious experiences
indicates to me that your seemingly logical objection that I am
introducing something outside the system merely shows that our current
grasp of logic isn't the be-all and end-all.

We touched on quantum physics earlier- I'm not sure that anyone has
quite worked out how to re-draw the scientific paradigm in the light of
quantum theory (was it not Feynman himself who said "no-one knows
how it can be like that, all we know is that it *is* like that") and there
may be further radical paradigm shifts on the way. Perhaps these things
will fall into place then. Who knows? But in the meantime I am happy to
have faith (apposite word given that we kicked off by discussing
religion) in the reality of qualia. You are apparently happy to have faith
in the validity of your argument against qualia, in spite of the evidence of
your senses. But I don't think you should deceive yourself that your
position doesn't involve a leap of faith.

(As an aside, if qualia don't exist, then is the edifice of science
threatened by the non-existence of the observations that underlie it? ;))


>You could theorize I suppose that the objectivity
>required for emergent properties is provided by society.

That might indeed work- we have to ask ourselves whether someone
raised in complete social isolation could have the experience of, say,
"redness" (though obviously they wouldn't have that label for it). Pass!

>
>>> I have, and I subscribe to the view that it would have been more
>> appropriately titled "Consciousness Explained Away".
>
>:) just as an aside it quite interesting to note the dichotomy of
>views on his book. No one thinks its ok or reasonably interesting just
>either prophetic truth or travesty. 

That is very true. There are some amazingly dichotomous reviews of it
on Amazon. 

> I actually don't agree with his
>ideas on the structure of the mind, but do on the bit about qualia in
>general sense

So I see!
>
>
>> >  Which
>> >if it isn't physical is dualistic. What is the other level you talk
>> >about? 
>> 
>> The level of subjective experience.
>> 
>This is where I will never even begin to understand... I can't see how
>'the level of subjective experience' can sit comfortably. 

For my part I can't fathom how someone can claim that 'qualia' (don't
really like that word but it'll do I suppose) don't exist. Don't get me
wrong, I understand the argument, I just don't think it's tenable in the light
of experience.

> What is
>this level? is it physical? mystical or what? 

It is experiential. Could even be mystical if you are that way inclined.
But experiential will do.
 
> I keep on asking this
>at the end of a post and you say you;ve answered above, but I can
>never see the explicit answer (becuase I don;t think there is one)or
>do you have a worldview that there just *is* a level of subjective
>experience?

Yes, I thought I had made that clear by saying that I see it as something
irreducible. Apologies if that wasn't clear.

> The problem is that if you cannot define or formulate it
>as more than that then you can't make any testable hypotheses

Actually you can, very easily. Example: I hypothesise that if I set fire to
my trousers, I will shortly afterwards experience the qualia of pain.

I trust you will forgive me if I don't test this hypothesis.

I know that's not what you really mean- but as I said before, the fact that
this part of my argument is not amenable to scientific scrutiny with our
current methodologies doesn't bother me unduly.

I can't "prove" that my depressed patients are unhappy, nor can they, but
I'm inclined to believe them.
 
> and then
>I find it difficult to accept.

I know. We are of different faiths. I sense we are not going to convince
each other, so I am happy to agree to differ.

regards 
-- 
Nick Medford




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