From: snodgras@cyber.net (John E. Snodgrass)
Newsgroups: sci.philosophy.tech
Subject: Re: nano-replicator assumptions
Date: 3 Oct 92 08:50:27 GMT
Organization: The Cyberspace Station

In article <1992Sep28.200723.86079@Cookie.secapl.com> frank@Cookie.secapl.com (Frank Adams) writes:


>>       RNA is a 'alphabetic' molecule. It was designed
>>(or evolved if you like) because it had the property that a large
>>number of different types of molecules could be put together from
>>a small number of parts

>       Designed or evolved makes a great deal of difference.  It
>seems to me that you are greatly overgeneralizing from the way
>the human design process works.  We tend to design things with
>*a* purpose in mind; only where required do we adopt
>multi-purpose parts.  Evolution, by contrast, makes multi-use the
>norm; only in special cases does a part specialize to a single
>purpose; and even then, it is quite likely to acquire additional
>purposes in the course of further evolution.  Consider the human
>mouth, for example: it has long functioned for both eating and
>breathing; more recently, it has added talking to its repertoire.

       Our tools are generally not as complex as our biological
structure. Also, 'multi-purpose parts' is poorly defined.
Something like the 'general purpose computer' could be viewed as
having an indefinate number of purposes. The point is, if people
could figure out how to make a good multipurpose tool (such as
Dr. Who's well known gizmo) they would; no doubt they eventually
will.

       On a deeper level, human technology is part of the evolved
bio-structure, like crab shells or termite nests. Thus the
attempt to separate human activity from activity pertinent to
evolution, or conversely to deny purpose (or purposeful design)
to non-human lifeforms, is anthropocentric. Humans are no
different from other lifeforms in any cosmologically significant
way. Without the purpose of attempting to survive, organisms
would not evolve. (But one cannot logically assert this purpose
also evolved.)

>       RNA evolved because it was (in the environment where it
>came into existence) self-replicating as well a store for
>information.

       The book that published itself. ;-> A misuse of the term
'information', which requires different systems to send and
receive it.

>>       There is no such thing as "just chance".

>       Even if you believe the universe is deterministic, this is
>an unreasonable statement.  If you shuffle a deck of cards
>repeatedly, eventually you will get all four aces on top of the
>deck.  When this happens, it is most reasonable to describe it as
>happening by chance.  There are all sorts of physical processes
>involved in the shuffling operation, but they did not in any
>interesting way cause the particular arrangement of the cards.

       What is 'interesting'? A robot could shuffle a deck
'deterministically', yet an observer might think it was random.
He would say: "The manner in which the deck came to be ordered is
not interesting." Error. What is not interesting is the
hypothesis of randomness. Who is to say that the origin of life
was 'random'?

>       Similarly, if you put a bunch of chemicals with the right
>elements into solution, with an external energy source to keep
>them within a certain energy range, eventually any given molecule
>formed from those elements will form.  In some cases, it will
>take a fraction of a second; in others, the average waiting time
>will be 10^100 years or longer.  This is the only sense of
>"chance" needed for my comments above.

       A logical approach to discovery prompts us to say: why
certain molecules form is not a matter of chance, but of the
nature of the elements and the environment they share. Let us
discover what actually happened. This would be interesting. :-)

       This is relevant to the discussion because the current
theories of origin, being unable to account for events, resort to
probabilities as explanation (just as QM does).

      [...]

>       What seems nearly certain is that the precursor [of genetic
>lifeforms] is not still around as an independent system, and is
>quite likely not around at all.

       Perhaps. But if it were not parasitic or infectious, (or
even if it were) it could be missed. Not a key point in any
argument for hierarchical cell control, however.

>>      At any rate, controlled mutation of this storage
>>information itself would become an important aspect of evolution.
>>But initially it was the mutation of the underlying system. This
>>type of mutation must still be occurring today, needless to say,
>>or at least that is a testable hypothesis.

>       What evidence do you have for such a thing?

>       What evidence is there against it?

       [ ...stuff deleted (as elsewhere)...]

>>       A block or string of material with no internal
>>organization is not a system. RNA was created _by_ a system to be
>>easy to copy, and this is why biologists have been able to copy
>>it: they just use a similar procedure to the one the cell uses.
>>This has led to the erroneous notion that it is self-replicating.

>       A system is what acts like a system.  What reason do you
>have to doubt the experimental results, other than an a priori
>belief that it must be wrong?

       No  experimental results have been doubted.
Interpretations have. The current plurality is that RNA was the
'self-replicating' molecule. However, RNA does not just
'replicate': things must be done to cause it to be replicated.
Thus, its status as prime replicator is open to interpretation.
Moreover, being a class of molecule which consists of _any order
whatsoever_ of certain nucleotides, it hardly fits the bill as a
'system'. Seriously.

>>       Are you suggesting the DNA molecule is "aware"
>>that certain things need to be accomplished, and subsequently
>>initiates them? If not, then why are you suggesting DNA plays an
>>active role?

>       I don't think *any* part of the cell is "aware" of
>*anything*.  Maybe your problem is that you think the opposite.

       Whether the cell, or parts of the cell, are 'aware' is an
open question. A cell is highly organized, to say the least.
Cells make up our brains, and perform the operations necessary
for us to imagine that we are engaging in purposeful thinking,
and that we possess 'awareness', and that we know what
'awareness' is. Who knows whether this is because cells or parts
of cells possess awareness? Perhaps a clearer definition of
awareness, or of cells, will give us more insight into the
matter.

>       What makes you think that these molecules *do* know where
>to go?  By and large, molecules created in a cell move around in
>no particular pattern. When they get to an appropriate receptor
>(i.e., a place where they are capable of having a chemical
>reaction) they react.

       Molecules may not individually 'know where to go', but
overall strict coordination of motion is necessary. The cell is
not just a bag of chemicals. It consists of innumerable and
highly organized substructures. These substructures are each
built up from proteins so complex that James Watson, for
instance, in his book "The Molecular Biology of the Gene", opined
that we may _never_ decipher their 3-D structure. These are huge
molecules, with gigantic molecular weights,  and they must arrive
in a timely manner at precise locations in the cell. Do you think
the cell depends of these monsters _diffusing_ to where they are
needed? Or look at the motion of RNA from the nucleus to the
cytoplasm. Simple diffusion? Again these are sometimes giant
molecules which wouldn't go anywhere in a simple solution. No one
knows how this is controlled. The suggestion that cell repair and
so on takes place by diffusion and 'receptors' is absurd.

>>      Why is infinite (or indefinate) regress rejected out of
>>hand?

>       First, it is philosophically distasteful.  It denies the
>possibility of ever *really* answer the question, "how does this
>work"?

       Let's hear from someone who thinks we'll ever figure out
how things ultimately work. Or let's hear from someone who thinks that
the purpose of science is to reach the plateau of 'total knowledge',
and finds this view 'tasteful'.

>([...] if there was strong evidence for an infinite
>regress -- 10 or so levels having been discovered, with no end in
>sight -- it would nevertheless be a good working hypothesis.)

       How would we know the end if we found it? We have already been
through quite a number of levels.

       [...stuff deleted...]

>>       No. The properties listed above are the result of
>>the interaction of the complex systems nature is made of.

>       No.  This sort of complex behavior emerges from very
>simple systems.  This is a mathematical fact.

       There is no such thing as a 'mathematical fact'. This is
like saying that the existence of Moby Dick is a 'literary fact'.
Also, there is the question of what is meant by 'complex'.

>       You might argue that it has no application to the real
>world; that complex behavior in the real world always arises from
>the "complex control systems interact[ing], each intent on
>maintaining the identity of its own system". But this ignores the
>fact that much real-world behavior is like the behavior of the
>mathematical systems.

       Only in that it is unpredictable. Otherwise it is
different -- in fact, to call the motion of a free pendulum, or
the computations of a computer program 'behavior' is just arguing
your point with semantics.

>       It ignores the fact that our best models of many complex
>systems (like the weather) have chaotic behavior like that of
>more simple mathematical models, and this behavior is like the
>actual system being modelled.

       The notion that because fractal modeling gives interesting
results on weather prediction doesn't make weather intrinsically
fractal. System models of large numbers of similar systems do
take on iterative and propagative qualities, because that is what
happens in such myriad-system environments. Weather is just a
chemical ecology. Iterative models are merely a type of system
model. One will find the same type of unpredictable yet organized
process at all levels of nature.

      John E. Snodgrass [snodgras@cyber.net]
Newsgroups: sci.philosophy.tech