mind/soul

Neil Rickert rickert at cs.niu.edu
Wed Oct 28 11:33:16 EST 1998


"Ray Scanlon" <rscanlon at wsg.net> writes:
>Neil Rickert wrote in message <715iua$8ur at ux.cs.niu.edu>...
>>"Ray Scanlon" <rscanlon at wsg.net> writes:

>>If N neurons have to meet up accurately with N locations, there are
>>N! (that's a factorial) ways of doing this.  Given that N is very
>>large, N! exceeds the total storage capacity of the known universe.
>>Therefore the DNA could not possibly encode such a high degree of
>>specificity.

>I don't know how this "coding capacity" argument go started but I have seen
>it again and again.

It probably got started because some people know how to count.

>                    It is a strawman.

Ah, yes.  In your idealogical committment to an absurd genetic
determinism, you must find ways to berate those who are capable of
seeing the evidence to the contrary.

>                                      It is allied to the view of the brain
>as a bowl of porridge with all the structure of oatmeal.

That "bowl of porridge" characterization is indeed a strawman that
ideological determinists use as an utterly false accusation of their
opponents.

>We are not talking about the possible permutations of n things taken n at a
>time. We are talking about the human (as a vertebrate) brain with between
>100 and 1000 billion neurons all precisely connected according to rules.

Right.  And precisely connecting means choosing one permutation among
many.  It is nonsense.

>Again and again and again in the brain, topology is preserved.

Whatever that means.  Without defining your terms, this is quite
meaningless.  If you define 'topology' loosely enough, then the brain
of a fish has the same topology as the brain of a human.  If you
define it restrictively enough, then a person's brain will have a
different topology tomorrow than it had today.

>                                                               There are
>about one million ganglion cells in the retina, their axons make up the
>optic nerve. The axons from one eye are joined at the optic chiasm by the
>axons from the other eye. The axons then split with the axons from the left
>half of both retinas continuing to the left brain and the right halves going
>to the right brain. the axons are completely scrambled in the nerve but upon
>arriving at the lateral geniculate nucleus (LGN), rule number one takes
>over. The axons split into six groups each having its destination in a layer
>of the LGN, three for the left eye and three for the right eye. The axons
>sort themselves out and restore the topology, neighbor by neighbor. The
>axons terminate on cells in the LGN.  Each layer contains a topological
>mapping of the retina.

If you are trying to impress me with jargon, don't bother.
It won't work.  I suggest you take a look at the recent book
"Lifelines:  Biology Beyond Determinism" by Steven Rose, who
is a biologist (Oxford University Press, 1998).  You should
be able to find a book review at
"http://www.anatomy.usyd.edu.au/danny/book-reviews/index.html".

>>>My disagreement is with your statement that the brain is not limited to
>>>signal energy flowing through the sensory neurons and information
>>>encoded in DNA. What is this other source?

>>For example, the chemical constituents of the air, the food, other
>>parts of the environment.

>Any molecule from the environment that desires to get to the brain must pass
>the blood-brain barrier. This is not easy and is a basic pharmacological
>problem when attempting to get medication to the brain.

This is silly.  That medication can get to the brain is already
enough evidence.  Moreover, there it is well know that nutritional
disorders affect brain function.

>Don't forget that I have never downplayed the environment.

Oh, complete bullshit.  You are driven by an ideology of genetic
determinism, and you make weak concessions to enviromental effects
when confronted with the evidence, only to take back those
concessions in your next paragraph.

>You say I am preaching dogma but I say I am merely reciting basic
>neuroscience.

Absolutely, you are preaching dogma, then trying to give it an air of
authenticity by rubber-stamping it with claims that it is basic
neuroscience.




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