Subject: Do We Want to Talk about the

Posted by Louis Macovsky on 2/27/2006
In Reply To:Do We Want to Talk about the Posted by Jay W. Forrester on 2/25/2006

Message:

Out from left field is my take on the discussion of purpose.

Slime mold cells have no goal other than their individual survival. Under a set of certain environmental conditions they, independently of any other slime mold cell's behavior or signal, secrete cAMP that acts pheromone-like and subsequently attracts nearby cells to come together to form a slime mold colony (swarm) that a naturalist will identify as a single organism moving with a common "goal" along the forest floor eating rotting wood and other organic debris. The cooperation and unity of the cells to form an "organism" easily mis-identified to be a single multicelled body is the "emergent system" with "emergent behavior" resulting from independent single cell systems that have independent behavior and goals. Under a new set of environmental conditions, the "single" slime mold dissolves into its independent cells that renew their independent life with again their independent goal of
single cell survival. (cellular slime molds: Dictyostelida and Acrasida)

The goal of defining the purpose of a system and system behavior can not ignore subsystem structure and behavior. The actual purpose or goal, if their is one, of a system is emergent just as is system behavior is emergent from the structure of linked submodels or sublevels (and the sublevels from their sublevels). [At present], I do not believe it is appropriate to look for and define the purpose of a system. We should emphasize emergent behaviors and then discuss sublevel or submodel function (influences of or on reinforcement and balancing feedback and the effect of delays). If there is a purpose it emerges from the bias of the question and problem presented by the modeler and his/her clients.

One word keeps coming to my mind from this discussion: Teleology.

Lou.