Wednesday, August 02, 2006

Decentralized Systems

Update: This post is a partial review of John Holland’s Hidden Order: How Adaptation Builds Complexity and Mitchel Resnick’s Turtles, Termites, and Traffic Jams: Explorations in Massively Parallel Microworlds.

Both John Holland (Hidden Order, 1995) and Mitchel Resnick (Turtles, Termites, and Traffic Jams, 1994) argue that it is difficult to discern the behavior of a system from the behavior of its parts. Through the use of computer modeling—cellular automata in Holland’s case, the StarLogo programming environment in Resnick’s—both attempt to begin to understand the nature of these complex systems.

cover of Holland's Hidden OrderHolland defines complex systems as a product of “the interactions” between their relatively simple parts (3). The result of these interactions, which are often relatively simple themselves, is that the “aggregate behavior of a diverse array of agents”, or the “parts” of the system, “is much more than the sum of the individual actions” of those parts (31). That is, the ordered behavior comes as a result of the particular way in which objects interact, rather than from any kind of centralized oversight, which is presumed to be the source of most ordered behavior. Holland gives the example of a city as a complex system that “retain[s]” its “coherence despite continual disruptions and a lack of central planning” (1). Now most cities obviously have central planning architectures in the form of governments, but those centralized authorities often find it their job to combat or enforce city behavior that does not originate directly (at least in appearance) from their decisions. Where do city-level features like traffic jams, ethnically- or economically-segregated neighborhoods, and homelessness come from? Rarely can they be directly attributed to central planning. Rather, the interactions between residents—which are often dictated by central planning organizations—and other structures in the environment help to form and maintain the city and its “personality.” This aggregate behavior results in “an emergent identity” that, though continuously changing, is remarkably stable (3).

cover of Resnick's Turtles, Termites, and Traffic JamsSimilarly, Resnick explicitly focuses on these “decentralized interactions” and the systems that result from them (13). He provides five “Guiding Heuristics for Decentralized Thinking”: 1) “Positive Feedback Isn’t Always Negative”, that is some kinds of positive feedback, in the economy for instance, can lead to increases, rather than decreases, in order; 2) “Randomness Can Help Create Order”; 3) “A Flock Isn’t a Big Bird”—systems do not behave like a larger version of their components; 4) “A Traffic Jam Isn’t Just a Collection of Cars”, or decentralized systems are more than the sum of their parts; and finally 5) “The Hills Are Alive”—the environment and context of a decentralized system are key components of its behavior (134).

Resnick sees the decentered view of the world as necessary to changing deeply-entrenched centralized ways of thinking. According to him, this decentered view became apparent in the work of Freud and his description of the unconscious, and other decentered metaphors have been slowly gaining ground in other fields since then.

This view of the world as being primarily the product of decentered behavior has interesting applications for rhetoric, for persuasive situations are as decentered and interaction-dependent as the systems studied by Resnick and Holland. Resnick notes that as decentered thinking—in the form of chaos and complexity theory—has gained traction, “scientists have shifted metaphors, viewing things less as clocklike mechanisms and more as complex ecosystems” (13). Rhetoricians since the sophists, however, have known the complex, dependent nature of communication, where “decentralized interactions” like the complex interactions of rhetorical appeals and “feedback loops” of self- and community-reinforcement (13) are well known.

These connections imply that rhetoric is well-suited for application of decentralized thinking. Certainly there is a tendency even in rhetoric to over-emphasize centralized behaviors to the detriment of decentralized ones—see the work of Peter Ramus. As rhetoric continues to move closer to a sophistic understanding of the power of persuasion, the models of Resnick and Holland have the possibility of shedding light on rhetorical situations, providing a language to explain behaviors that, though recognized, might have been previously unexplainable.

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