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MIT Encyclopedia of the Cognitive Sciences - Cryptome

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738 Self-Organizing Systems<br />

issue is whe<strong>the</strong>r life itself came into existence through a<br />

self-organizing process. Those who have used computers to<br />

explore <strong>the</strong> ma<strong>the</strong>matically self-ordering properties <strong>of</strong> complex<br />

adaptive systems have studied this subject under <strong>the</strong><br />

rubric <strong>of</strong> ARTIFICIAL LIFE. Those whose definition <strong>of</strong> life is<br />

less formal have looked for chemical conditions in <strong>the</strong> early<br />

history <strong>of</strong> <strong>the</strong> planet in which some form <strong>of</strong> prebiotic selection<br />

might have amplified <strong>the</strong> autocatalytic properties <strong>of</strong><br />

self-organizing protocells into functional, adapted traits.<br />

Such studies begin with <strong>the</strong> plausible insight that life probably<br />

did not originate solely in <strong>the</strong> accidental assembly <strong>of</strong><br />

nucleic acids, but in <strong>the</strong> coevolution <strong>of</strong> proteins and nucleic<br />

acids, with protein evolution perhaps playing <strong>the</strong> leading<br />

role. Sidney Fox’s pioneering work on proteinoid microspheres<br />

reveals <strong>the</strong>m to be spontaneously self-organized systems<br />

that might have provided <strong>the</strong> hydrophobic boundaries<br />

within which <strong>the</strong> subsequent coevolution <strong>of</strong> protein and<br />

nucleic acids can take place (Fox l984). Harold Morowitz’s<br />

and David Deamer’s notion <strong>of</strong> abiotically forming vesicular<br />

amphiphile bilayers provides ano<strong>the</strong>r possible such “cradle”<br />

for <strong>the</strong> emergence <strong>of</strong> life (Morowitz, Heinz, and Deamer<br />

l988). Manfred Eigen’s notion <strong>of</strong> hypercycles provides a<br />

model <strong>of</strong> how this interaction might have occurred. One can<br />

think <strong>of</strong> a hypercycle as a system <strong>of</strong> linked autocatalytic<br />

cycles, in which each member is catalyzed by at least one<br />

o<strong>the</strong>r member (Eigen and Schuster l979.)<br />

A second issue is <strong>the</strong> relationship between natural selection<br />

and self-organization once life is up and running. On<br />

<strong>the</strong> face <strong>of</strong> it, self-organization rivals natural selection as <strong>the</strong><br />

basis <strong>of</strong> both individual development and <strong>of</strong> <strong>the</strong> larger contours<br />

<strong>of</strong> phylogenetic order. For <strong>the</strong> acquisition <strong>of</strong> functional<br />

traits by self-amplifying feedback is not <strong>the</strong> same thing as<br />

selection-by-consequences by means <strong>of</strong> a forcelike “selection<br />

pressure” that operates against an inertial, and indeed<br />

inert, dynamic background, which is how natural selection<br />

is usually conceived. The notion that self-organization and<br />

natural selection are rivals has been defended by several<br />

authors (Goodwin l994; Oyama l985; Sal<strong>the</strong> l993). A more<br />

integrative, mutually reinforcing approach is, however, possible.<br />

Recognizing that when any system analogous to Boolean<br />

networks is set into motion it can be expected<br />

spontaneously to explore its space <strong>of</strong> future states and if<br />

mild “fitness” conditions are imposed it can be expected to<br />

reach peaks on “adaptive landscapes.” Kauffman, Holland,<br />

and o<strong>the</strong>rs who have studied genetic algorithms and EVOLU-<br />

TIONARY COMPUTATION have suggested that “spontaneous<br />

order is available to natural selection for <strong>the</strong> fur<strong>the</strong>r selective<br />

crafting <strong>of</strong> well-wrought designs” (Kauffman l993: l;<br />

Holland l995). One might readily imagine, in accord with<br />

this suggestion, that natural selection has stabilized <strong>the</strong> selforganized<br />

life cycle <strong>of</strong> slime molds, and in <strong>the</strong> process has<br />

conferred an explicitly biological function on a spontaneously<br />

generated pattern. Kauffman himself argues that <strong>the</strong><br />

regulatory systems <strong>of</strong> genetic networks, among whose many<br />

nodes much connectivity and parallel processing are at play,<br />

are self-organizing, functionally decomposable (see FUNC-<br />

TIONAL DECOMPOSITION) systems that have been stabilized<br />

by natural selection in this way. Weber and Depew have<br />

argued that, considered as a natural phenomenon in its own<br />

right, natural selection emerges only in autocatalytic chemi-<br />

cal systems that have managed to internalize information in<br />

macromoleules, <strong>the</strong> error rate <strong>of</strong> which provides <strong>the</strong> fuel <strong>of</strong><br />

natural selection (Weber and Depew l996). In this account,<br />

genes have <strong>the</strong> function <strong>of</strong> enhancing and stabilizing <strong>the</strong><br />

coupling between organism and environment that selforganization<br />

first generates.<br />

The human brain has about l0 l0 neurons, any <strong>of</strong> which<br />

can have up to l0 4 connections with o<strong>the</strong>r such neurons,<br />

stimulated and regulated by a large number <strong>of</strong> chemical<br />

neurotransmitters. This fact alone brings <strong>the</strong> study <strong>of</strong> cognitive<br />

and o<strong>the</strong>r psychological phenomena within hailing distance<br />

<strong>of</strong> <strong>the</strong> study <strong>of</strong> self-organizing complex systems. This<br />

distance has been reduced by those advocating DYNAMIC<br />

APPROACHES TO COGNITION, who recognize that learning is<br />

a process that occurs only in systems that are “environmentally<br />

embedded, corporeally embodied, and neurally<br />

entrained” by feedback (see Port and Van Gelder 1995;<br />

Smith and Thelen 1993; Kelso 1995; Cook and Murray<br />

l995). If digital computationalism gives way to more<br />

dynamical studies <strong>of</strong> connectivity in neural networks, selforganization<br />

can be expected to play a more prominent role<br />

in both <strong>the</strong> ontogeny and phylogeny <strong>of</strong> mental functions.<br />

The purely adaptationist stories people like to tell about <strong>the</strong><br />

Pleistocene origins <strong>of</strong> localized mental functions (Barkow,<br />

Cosmides, and Tooby l992), as well as <strong>the</strong> inclination to<br />

model neurological development closely on Darwinian<br />

mechanisms (Edelman l987), might <strong>the</strong>n give way to a more<br />

nuanced view, in which neural organization is taken to be<br />

governed in part by self-organization working through<br />

intense feedback between organism and environment.<br />

See also ADAPTATION AND ADAPTATIONISM; COMPUTA-<br />

TION AND THE BRAIN; EVOLUTIONARY PSYCHOLOGY<br />

—David Depew and Bruce Weber<br />

References<br />

Barkow, J., L. Cosmides, and J. Toomy. (1992). The Adapted Mind.<br />

New York: Oxford University Press.<br />

Cook, J., and J. D. Murray. (l995). Pattern formation, biological. In<br />

M. A. Arbib, Ed., Handbook <strong>of</strong> Brain Theory and Neural Networks.<br />

Cambridge, MA: <strong>MIT</strong> Press, pp. 705–710.<br />

Dyke, C. (1988). The Evolutionary Dynamics <strong>of</strong> Complex Systems.<br />

Oxford: Oxford University Press.<br />

Edelman, G. (1987). Neural Darwinism. New York: Basic Books.<br />

Eigen, M., and P. Schuster. (1979). The Hypercycle. Berlin:<br />

Springer.<br />

Fox, S. (1984). Proteinoid experiments and evolutionary <strong>the</strong>ory. In<br />

M.-W. Ho and P. T. Saunders, Eds., Beyond Neo-Darwinism.<br />

London: Academic Press, pp. l5–60.<br />

Garkinkel, A. (1987). The slime mold Dictyostelium as a model <strong>of</strong><br />

self-organization in social systems. In F. E. Bates, Ed., Self-<br />

Organizing Systems: The Emergence <strong>of</strong> Order. New York: Plenum<br />

Press.<br />

Goodwin, B. C. (1994). How <strong>the</strong> Leopard Changed Its Spots: The<br />

Evolution <strong>of</strong> Complexity. London: Weidenfeld and Nicolson.<br />

Holland, J. A. (1995). Hidden Order: How Adaptation Builds<br />

Complexity. Reading, MA: Addison-Wesley.<br />

Jantsch, E. (1980). The Self-Organizing Universe. Oxford: Pergamon<br />

Press.<br />

Kauffman, S. A. (1993). The Origins <strong>of</strong> Order: Self-Organization<br />

and Selection in Evolution. New York: Oxford University<br />

Press.

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