I wish to reply to Don Mickulecky:
> One big question still looms overhead: how much of this kind of "complex
> ity"
> can really be caught by computer simulation, if any?
I cannot answer this question at present but I hope I can contribute some
ideas for further discussion.
A mechanistic system, as I understand it, operates under a sequential causality.
(i.e. A causes B which causes C etc). The notion of algorthim and Turing-
computable is also inherently sequential (even with massively parallel models
one needs a sequential algorithm to do something "useful"). This sequential/
mechanistic paradigm is much easier for a human observer to visualise and it
is therefore difficult to give up this approach.
In contrast, an important idea being developed by the ICS group in Germany
is that of *simultaneity*. Living or cognitive systems could be modelled
as networks where one event can express itself *simultaneously* in different
forms. The precise form is context-dependent (or standpoint-dependent). An
example is a lecture being listened to by several people. Within the brain
of each listener the utterances express themselves differently, since each
listener has constructed his/her own individual context.
> These ideas intertwine with an idea of Rosen's that we measure things
> convenient to us inspite of the possibility that the natural system is not
> using those observables in any meaningful way at all!
I would understand this as follows: if we choose to make measurements
according to a mechanistic conception, there will always be some non-
deterministic effects that don't fit in. (It doesn't matter how "good"
the conception is - in the sense that it "works" as an explanation a large
part of the time - it will always be incomplete).
The unexpected effects could be modelled as follows: they are the forms of
expression (in our current context/measuring system) of sequences of events
taking place simultaneously in contexts which are "inaccessible" to us (after
all we can only pay attention to one context at a time and that is the current
mechanistic model we are using). The other "contexts" are alternative positions
of description we could take but which could not be mechanistically "added"
to the current model without contradiction. Effectively this is a form of
dialectic.
I will try to give an example: somebody says something I don't understand,
i.e. in my internal context, the expression has taken on an unintelligible form
but in the other person's internal context it makes perfect sense. Instead of
mixing these two viewpoints together into a single mechanistic system (which
would lead to contradictions) they should be considered as seperate systems
with a simultaneous non-mechanistic relationship between them.
In other words, a living or cognitive system could be approximated as a network
of event sequences where each event may or may not have *simultaneous
translations* within the operation of neighbouring event sequences.
It is precisely these "simultaneous translations" which cannot be reduced to a
mechanistic system, and they are necessary if a system is to be "alive".
As a possible step towards the future formalisation of such networks, an
idea for the extension of classical logic has been proposed by German
philosophers. I have written a summary of my understanding of their ideas
in a seperate paper: "Logical Problems in Cognitive Modelling". If anybody
is interested, Cliff has a copy on
ftp://kong.gsfc.nasa.gov/pub/joslyn/Kennedy,_Catharina_paper
To return to the question above: I do not know how far we can approximate
certain aspects of such simultaneous networks on a v.Neumann computer but
it is just possible that a formalisation will be found and it will be a
matter of developing a new parallel computer architecture which provides
the operations to implement such simultaneous translations.
Trying to define "simultaneous" will definitely require another posting.
I hope I have made myself clear. My understanding of this issue is still
developing.
The ICS (Institute for Cybernetics and Systems Theory) in Bochum, Germany
should have its home page early next year.
I have only read a little of Rosen's work. Could anybody give a list of
his publications?
regards,
Catharina
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Catharina Kennedy, ck@ics.inf.tu-dresden.de,
PhD student, Institute for Artificial Intelligence,
Faculty of Computer Science,
Technical University of Dresden,
01062 Dresden, Germany.
Tel: +49 351 4575 490
Fax: +49 351 4575 335
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