Re: Reductionism - was: Young but distant gallaxies
Posted by
Kenneth Lloyd on
URL: http://friam.383.s1.nabble.com/Young-but-distant-gallaxies-tp839193p1075204.html
Steve,
Good job on the defense of a reductionist position. I
utilize a five phase approach to the study of complex
systems.
Definition - Analysis - Normalization - Synthesis -
Realization (DANSR)
Reductionism has its place in the analytical phase
at equilibrium. Analysis is normally a study of integrable, often linear
systems, but it can be accomplished on non-linear, feed-forward systems as
well. The synthesis phase puts information re: complex behavior
and emergence back into the integrated mix and may be "analyzed" in non-linear,
recurrent networks. This is actually a probabilistic inversion of
analysis as described in Inverse Theory.
Bayesian refinement cycles (forward <-> inverse) are
applied to new information as one progresses through the DANSR cycle. This
refines the effect of new information on prior information - which I hope folks
see is not simply additive - and which may be entirely disruptive (see
evolution of science itself) .
The fact this seems to work for complex systems is
philosophically uninteresting, and may ignored - so the discussion can
continue.
Final point: Descartes ultimately rejected the concept
of zero because of historical religious orthodoxy - so he personally never
applied it to the continuum extension of negative numbers. All his original
Cartesian coordinates started with 1 on a finite bottom, left-hand boundary -
according to Zero, The Biography of a Dangerous Idea, by Charles
Seife.
Ken
Orlando-
You can find good
references in Wikipedia on this topic,
including the Descartes references.
Reductionism
From Wikipedia, the
free encyclopedia
Descartes held that non-human animals could be
reductively explained as automata — De homines 1662.
Reductionism can
either mean (a) an approach to understanding the nature of complex things by
reducing them to the interactions of their parts, or to simpler or more
fundamental things or (b) a philosophical position that a complex system is
nothing but the sum of its parts, and that an account of it can be reduced
to accounts of individual constituents.[1] This can be said of objects,
phenomena, explanations, theories, and meanings.
All -
IMO,
Reductionism(a) is a highly utilitarian
approach to understanding complex problems, but in some important cases
insufficient. It applies well to easily observable systems of distinct
elements with obvious relations operating within the regime they were
designed, evolved, or selected for. It applies even better to engineered
systems which were designed, built and tested using reductionist
principles. I'm not sure how useful or apt it is beyond
that. Some might argue, that this covers so much, who cares about
what is left over?... and this might distinguish the rest of us from
hard-core reductionists... we are interested in the phenomena, systems, and
regimes where such does not apply. This is perhaps what defines
Complexity Scientists and Practitioners.
Reductionism(b) is a
philosophical extension of (a) which has a nice feel to it for those who
operate in the regime where (a) holds well. To the extent that most of
the (non-social) problems we encounter in our man-made world tend to lie (by
design) in this regime, this is not a bad approach. To the extent that
much of science is done in the service of some kind of engineering (ultimately
to yield a better material, process or product), it also works
well.
Reductionism(b) might be directly confronted
by the "Halting Problem" in computability theory. Reductionism in
it's strongest form would suggest that the behaviour of any given system could
ultimately be predicted by studying the behaviour of it's parts.
There are certainly large numbers of examples where this is at least
approximately true (and useful), otherwise we wouldn't have unit-testing in
our software systems, we wouldn't have interchangeable parts, we wouldn't be
able to make any useful predictions whatsoever about anything. But if it
were fully and literally true, it could be applied to programs in
Turing-Complete systems. My own argument here leads me to ponder
what (if any) range of interesting problems lie in the regime between the
embarrassingly reduceable and the (non)-halting program.
But to suggest
(insist) that *all* systems and *all* phenomenology can be understood (and
predicted) simply by reductionism seems to have been dismissed by most serious
scientists some while ago. Complexity Science and those who study
Emergent Phenomena implicitly leave Reductionism behind once they get into
"truly" complex systems and emergent phenomena.
I, myself, prefer
(simple) reductionistic simplifications over (complex) handwaving ones (see
Occam's Razor) most of the time, but when the going gets tough (or the systems
get complex), reductionism *becomes* nothing more than handwaving in my
experience.
- Steve
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