ABSTRACT
An important feature of nearly all complex adaptive systems (CASs) is that their general behavior patterns are not determined by centralized decision makers (“deciders”), but rather are determined by the net results of interactions between anumber of independent entities (modules or variables). It is these network interactionsthat contribute to aCAS’s complexity. Each individual entity (and class of entity) acts on the CAS with a built-in, basic set of behavioral rules. (One of the rules must be that the elements of the CAS act together.) We see this “whole is greater than the sum of the parts” property in the colonial behavior of ants, bees, and termites; migrating birds; and schooling Ÿsh. The coordinated behavior in the complex human immune system (hIS) involves agreat number of different classes of hIS cells, and their biochemical rules are essentially their programmed responses to received external chemical signals, and those secreted by other hIS cells forming ahormonal/cellular “network.” Even the innate IS involving the reactions of complement proteins and NK cells follows “preprogrammed” biochemical rules.
