human vs machine

Wed Aug 9 18:57:03 EST 1995

M. Ferber (Ferber at wrote:
: tgmk at (TGMk) wrote:
: >Any fool can see that with enough elements one could make a brain
: >out of non-biological materials. But how many would you need?  That 
: >is, how many neurons are in the (typical) human brain?  We have an old
: >biology book that says *at least* 100 billion but I'll bet there are >more.
: >And how many connections do they each have?  Of course, this is basic
: >AI stuff but I'm too lazy to go to the library.  Pls send reply to 
: >TGMK at   Thanks! 

[Description of inset neurology deleted]
: The problem mentioned by tgmk (whoever he or she is) is not simply 
: related to the number of neurones. The fact is that the connections 
: between the elements of any nervous system are specific. Furthermore each 
: element (neuron) within a nervous system is connected to many other 
: neurones. There are no simple 1 to 1 connections. For the human brain an 
: average of 1000 connections per neuron has been suggested. This togerther 
: with the 10 exp 12 ( neuornes makes 10 exp 15 
: connections or synapses. Is it really possible to put such a number of 
: elements together to a synthetic brain. I think it is not. 

: Regards 
: Micahel Ferber

This is an interesting question.  I think that, in theory, few people
disagree that it would be possible to model the neurochemical system
(in the worst case) that a brain uses to go about its business.  This is
NOT to say that we have the capabilities for this scale of modelling
available at this time.  Instead, I would suggest that some day such
a model might be plausible.

On the other hand, most people seem to forget that digital computers
are a vastly different medium than wetware.  Digital computers just
aren't good at analyzing and simulating the analog signals involved
in psychophysiology.  Plenty of people may argue that "neurons only
give off spikes, which can be represented digitally."  That's all
well and good, but what about the other factors?  What about cell
physiology and neuromodulators and hormones that affect the spike
rate?  How are we to measure these parameters in a digital world?
I would answer that we shouldn't.  If machines will think, it will be
it their own unique way.  There is no way to sequence the DNA of a
computer, so why should we assume that they will think the same way
that we do?  Hell, they can even do MATH better than we can. :)
And remember, a good algorithm is worth an infinite amount of space.
Can anybody remember all the whole numbers?  Doubtful.  But I'm sure
most of you know the tried-and-true algorithm x_n+1 = x_n + 1.
Some problems may not be reducible in this nice way, but who knows
for sure?

-Jason Kinner
(jkinner at

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