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From: bpvanstr@yoho.uwaterloo.ca (Brian Van Straalen)
Subject: Re: LIFE? (was Evolvable Code....)
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References: <CunE0D.6Dn@watdragon.uwaterloo.ca> <33hv57$s7p@Germany.EU.net> <CvD1CK.7F0@watdragon.uwaterloo.ca> <1994Aug30.205015.23586@msuvx2.memphis.edu>
Date: Wed, 31 Aug 1994 19:09:46 GMT
Lines: 87

In article <1994Aug30.205015.23586@msuvx2.memphis.edu>,
Mark C. Langston <umlangston@cc.memphis.edu> wrote:
>In article <CvD1CK.7F0@watdragon.uwaterloo.ca>, bpvanstr@yoho.uwaterloo.ca (Brian Van Straalen) writes:
>> In article <1994Aug29.223840.23541@msuvx2.memphis.edu>,
>> Mark C. Langston <umlangston@cc.memphis.edu> wrote:
>>>In article <CvBIJq.L84@watdragon.uwaterloo.ca>, bpvanstr@yoho.uwaterloo.ca (Brian Van Straalen) writes:
>>>> In article <1994Aug29.141340.23499@msuvx2.memphis.edu>,
>>>> Mark C. Langston <umlangston@cc.memphis.edu> wrote:
>>>>>
>>>>>Several.  There are two things I'd like to see brought into this whole
>>>>>  discussion, namely:  necessity and sufficiency.  Not only would this
>>>>>  delineate the argument and make it clearer, it would give us a solid
>>>>>  platform for which to work.
>>>>>
>>>>>E.g.,  is reproduction necessary for life?  Is it sufficient?  You seem to
>>>>>  be saying that neither is the case.  Well, clearly, all life reproduces.
>>>>>  (and that's life qua life, so no case studies of infertility, please. :)  ).
>>>> 
>>>> Sorry , no.  The whole point of the above discussion was the total
>>>> DENIAL of this dogma.   
>>>> 
>>>
>>>Would you show me an example of a species that doesn't reproduce?  (and I
>>>don't mean mules, since the whole point of the above conversation was to
>>>show that mules _do_ reproduce).
>> 
>> this is not a discussion of species.  the point of other discussions was mule
>> reproduction.  MY article dealt specifically with separating life and
>> reproduction.  I also brought up the point that more rigorous definitions
>> of reproduce were needed 
>> (the example of the table). I will reiterate:  Mules don't reproduce.
>
>
>  Forgive me.  For some reason I thought the whole point of talking about
>mules was to make a point about inclusion of members in the category life.
>From now on, I promise I won't try to transfer, infer, or generalize when
>writing.  Of course, only if you promise not to have pointless discussions
>about mules that have no relation to this group's charter. ;-)
>
>  Secondly, I agree that life and reproduction are seperate issues.  I simply
                           
	that's all I wanted to show.  Thank you.

>challenged you to show me a living system that didn't reproduce.  And _I_
>reiterate:  MULES DO REPRODUCE!  If mules did not reproduce (using a
>surrogate), when where the hell are we getting all these mules?  If you insist
>on your criteria, then plants don't reproduce, either.  Pardon me, I think
>I'll go trash my hedge trimmers, bud clippers, and lawnmower now.
>

Alright, I'll throw rhetoric around too.  Tables reproduce, by your 
allowances (after all, where else are we getting all these tables).  Man
steps in and mates nails with wood, viola, a table is born.  How does my
criteria dissallow plants from reproducing ? 


Look, I have a very pragmatic reason for harping on this issue of separating
reproduction and life.  Initial ALife forms were extremely simple.  So simple
that with a good computer you could wait around a million generations for
interesting behaviour to develope.  As ALife forms become increasingly
complex, the burden on computer resources will be stretched beyond it's
limit.  We are already running many of the better simulations on 
supercomputers.  When we are ready to develope alife form comparable to
a modern organic life form, the current computers will maybe be able to handle
one individual in a challenging environment.  One generation could well
take a day to compute.
	It's the same dilemna that wet geneticists found themselves in.
The more complex the life form you try to tinker with, the longer the turn
around time for results. That's why fruit flies became the bug of choice
for early radiation research: simple, SHORT life span, many generations
can be viewed.  I have a hard time seeing a real time simulation of one
fruit fly, much less a population.  I think a scientist will wither to
dust before he gets a thousand generations of compu-drosphilia (even with
the current increasing rate of computer power).

	So where does that leave us ? If we insist on reproduction for life,
then we will very soon run against the hardware barrier (in some senses, we
are already pressed against the hardware wall).  The hardware wall is moving,
yes, but alife research will have to sit patiently while NEC, CRAY, TOSHIBA,
IBM, etc. provide new tools, which we will quickly exhaust, and have to 
wait again.  It could very well take many decades for an alife form to
achieve the behavioural complexity of wet life.

	Thoughts?....

rest of article deleted for bandwidth
actually, rest of article deleted because I'm sick of this thread
