why study neurology?

Nick Medford nick at hermit0.demon.co.uk
Tue Jan 15 21:24:54 EST 2002


In article <43525ce3.0201151648.edbd983 at posting.google.com>, mat
<mats_trash at hotmail.com> writes

<snipped to preserve brevity as far as possible, no disrespect intended>

>What you take as evidence of qualia are things ineffable - the redness
>of red, the feeling of pain etc. I take the very fact that we can't
>describe them outside themsevles to be evidence that they don't exist
>in the strong sense you propose.  I can't describe redness objectively
>because it doesn't exist.  All I get to know is that an object is red.
> I can make no more investiagtion of the redness becuase I think it is
>simply a piece of knowledge.

Right- an irreducible piece of knowledge or experience- as I have been
arguing. This doesn't mean it doesn't exist.

>> > You make
>> >the assumption that becuase science as yet cannot describe even the
>> >simplest operations of the brain
>> 
>> Actually, I think we can already describe quite a few operations of the
>> brain
>
>which? :) on a broad general level, but not in an anyway detailed
>manner. 

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.

>
>> You misread me: I make no such assumption. The point I am trying to
>> make- indeed the reason I got involved with this thread- is rather more
>> subtle. Even if some biochemical marker for "being in love" were to be
>> discovered tomorrow, this would not "describe" or "explain" the
>> experiential phenomenon of love. I do not object to the idea that such
>> experiences require a biological, neural substrate. I think it is highly
>> unlikely that we can experience anything without such a substrate!
>>
>You are putting forward the belief that the explanation of experience
>is not exhausted by the "science" of the brain.  Similar position as
>David Chalmers et al. then?

Yes, albeit with reservations about Chalmers' idea of "proto-
panpsychism" if I remember his terminology correctly. But in the sense
that he sees conscious experience as a fundamentally irreducible
phenomenon, I'm with Chalmers.

>  Dualism. 

Except I don't see it as dualism. If consciousness is viewed as an
emergent property, it can be irreducible *without* appeals to dualism or
any special "mind stuff" (cf your comment below).

To use another example that one of my tutors was fond of (sorry I don't
know it's original provenance):

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.  

As a tangent- but one that it is relevant to the wider discussion- the
motorbike's motion cannot even be predicted from a complete
knowledge of its parts, because it also depends on the external
environment e.g. the friction of the road surface. Similarly (but in a
massively more complex fashion) the activities of consciousness depend
on interaction with environment. Indeed some (notably Jarvilheto) argue
that it is meaningless to discuss "consciousness" as a closed system
arising from brain, that the term only has meaning when applied to an
interactive system involving the external environment. I don't know if I
would go that far, as I can't conceive of a situation in which the brain
cannot interact with the environment, although perhaps the mere fact that
such a situation is inconceivable is a point in the argument's favour.
 
>I don;t know if you've read Consciousness
>Explained by Dennett 

I have, and I subscribe to the view that it would have been more
appropriately titled "Consciousness Explained Away".

>put he puts forward a similar example (but comes
>to a different conclusion)  A neuroscientist is intrested in how the
>brain processes colour.  Only problem is she has a retinal defect such
>that she can only see in two colours.  However she spends her whole
>life studying the neural basis of different peoples' brains and
>particularly how they process on seeing the colour red.  Your
>conclusion would be that howevr much she investigates she will never
>have the subjective experience or quale of seeing red?

Yes.

> But how can you
>be so sure? 

Ultimately I can't be. I would not claim to be 100% certain. But I would
favour that conclusion based on my subjective experience and my
impression of other people's experience. Scientific? No. Common sense?
It seems so to me, though I accept it does not seem so to you.

> How do you know that once we have explored the brain in
>all its depth that we couldn't explain subjective experience in what
>we found? 

I don't, but I fail to see how the raw experience can be completely
"understood" by studying its mechanics. To return to our Zen motorcycle
(ahem), I don't accept that the experience of travelling at speed would be
completely understood by someone who had studied the mechanics of the
bike but never ridden on one. That is a nice example because, unlike our
friend Monochrome Mary, it is not purely hypothetical- it is already
possible with current understanding to have a complete knowledge of the
underlying physics. (So would you argue that someone with that
knowledge would have a complete understanding of the experience of
motion, without having actually had the experience?) 

Indeed you seem to agree with me above when you say that you can't
describe "redness". Except you say you can't describe it because it
doesn't exist, whereas I say I can't describe it because it's irreducible
and thus not amenable to description. 

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. I
have to say that the latter position strikes me as the more common-sense
one!

>On recollection the Mary the Colour Scientist example is not
>Dennett's, he just uses it.  Don't know who came up with it first.

I think it may have been Searle, but I'm not sure either.

>> Hopefully you will see from the above example that one does not need to
>> be a dualist to take this position.
>> 
>It is indeed dualism!  If you're saying that cells, proteins, ions,
>etc in the brain - the biological and physical 'stuff' - is not enough
>to explain the mind then you must be positing a 'mind stuff'.

Well, I have tried to answer this above.

>  Which
>if it isn't physical is dualistic. What is the other level you talk
>about? 

The level of subjective experience.

> It can't be another part of the neurones or glia becuase then
>I would totally agree with you.  The qualia or subjective nature of
>experiences that you want included must occur in a 'mind stuff'.

Again I think I have covered that above.

>I was taught religion for quite a while.  Most systems have their very
>strange beliefs (usually involves coming back from the dead in some
>way).  Simply because they are so popular and rooted in our society
>that no-one bats an eye doesn't mean they have any inherent truth. 

Sure, I agree with that entirely. 

>And I don;t want any psychoanalytic theory on reactionary tendencies
>to enforced religious learning thanks! :)

LOL

Wouldn't dream of it... although it's interesting that you mention it... why
do you think you did that...;) 

Anyway thanks for the response, I feel we have got to the nitty-gritty
now. 

regards
-- 
Nick Medford




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