الجمعة، 8 مايو 2009

closed/open systems

Is every attempt at definition an attempt at closure? Are there open definitions? 

closed system in statistical thermodynamics is one in which the number of particles as well as the total energy are fixed by boundary conditions. Closed systems systems tend towards equilibrium and to increse in entropy.

For a living system, equilibrium corresponds to death. Living systems are open systemsthermodynamic systems persistently displaced from chemical equilibrium. Wolfgang Kِhler, the Gestalt psychologist, was the first to introduce the distinction between closed and open systems into theoretical biology. (See Mitchell G. Ash, Gestalt Psychology in German Culture, 1890-1967) In response to the challenges of Hans Driesch, Kِhler extended the Gestalt concept to biology in 1924 by elaborating the concept of self-regulating "open" systems, which he distinguished from those described by analytical mechanics. (see field

Alvin Toffler describes the ideas of Prigogine and the Brussels school as follows: "Summed up and simplified, they hold that while some parts of the universe may operate like machines, these are closed systems, and closed systems, at best, form only a small part of the physical universe. Most phenomena of interest to us are, in fact, open systems, exchanging energy or matter (and, one might add, information) with their environment. Surely biological and social systems are open, which means that the attempt to understand them in mechanistic terms is doomed to failure." (Order Out of Chaos, p. XV)

But for a theory of genetic determination to hold, the organism must be thought of as a closed system, in which the action of external stimuli and events are constant in relation to genetic difference. This is the only context in which one can claim that the presence of a specific gene or set of genes is a necessary and sufficient condition for the production of specific morphological characters. This position usually leads to an "atomistic" concept of the organism. 

An autopoetic system is both closed and open. It is operationally closed, following a circular logic of self-production, but it is materially and energetically open. Niklas Luhmann calls autopoetic systems " complex self-referential systems." These systems make and continue to make a difference between the system and its environment. Luhmann describes complex self-referential systems as "hypercomplex," in the ways that they make distinctions between themselves and their environments, but also internalize the distinction in a paradoxical "re-entry" of the distinction into the distinguished. 

The history of an open system is part of its structure, and Prigogine links open systems to irreversibility. Prigogine calls open systemsdissipative

epistemology of open systems: 

Logical verification, such as proof, is only possible in closed systems, purely formal structures which do not allow for extenuating circumstance. The classical statements of logical positivism describe analytic statements as "true solely in virtue of the meaning of the constituent symbols." (A.J. Ayer) The collapse of logical positivism in relation to the sciences is because natural systems are never closed. (see Naomi Oreskes et. al. "Verification, Validation, and Confirmation of Numerical Models in the Earth Sciences," Science 4 Feb, 1994) For the authors, the establishment that a model (cf metaphor ) accurately represents the "actual processes occurring an a real system" is not even a theoretical possibility. A model, like a novel, can " resonate" with nature, can "ring true", but fundamentally the reason for modelling is lack of access. But is the goal of scientific theories truth or empirial adequacy? Is the distinction between verification and validation relevant, insofar as validation is an establishment of legitimacy, typically given in terms of contracts, agreements, and methods? 

(Kant's critique of pure reason is an attempt to show us that closed systems can tell us about the world, that they are a priori and synthetic)Kurt Gِdel proved that even closed systems depend on unprovable theorems.(See Nagel and Newman, Gِdel's Proof) 

Much of the discussion between Kuhn, Lakatos, Popper, and other philosophers of science concerns the modification of scientific models in the light of recalcitrant data. When is it appropriate to modify the model, and at what point does one discard the model altogether? (in this context, Popper's claims of falsifiability seem simplistic in practice, if not in theory) Pierre Duhem and W.V. Quine have argued that scientic theories are underdetermined: that more than one theory can account for the same data, and that scientific theory is wholistic. (See Sandra Harding, ed. Can Theories be Refuted?) Not only can social and political factors be related to choices between competing theories, but even traditional maxims such as Occam's razor are extraevidentiary, metaphysical assumptions about the world.

In Personal Knowledge, Michael Polanyi develops an epistemology, inspired by biology, that he describes as neither subjective nor objective, but personal. Polanyi describes life and evolution as having been originated by the action of an ordering principle, which is the potentiality of a stable open system. (p. 384) It is the fundamental property of open systems that they stabilize any improbable event that serves to elicit them. Thus random events can be said to release the action of an ordering principle, while environmental conditions and the effects of chemical and physical systems can sustain it.

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