On the role of complexity in systems theory

Abstract

It has become common to describe complexity science as a new approach to many scientific questions that are less amenable to the usual “mechanistic view” of reality in science. However, we believe that the contrast implied here is to a large extent artificial. First of all, complexity features can appear even in the most basic systems in physics, as we will demonstrate. Secondly, instead of distancing itself from reductionist techniques, complexity science should benefit from the lessons learned from more mature fields, such as theoretical physics. In order to profit from analogies with this field, the generic aspects of complexity and systems problems have to be identified, rather than their specific manifestations at different hierarchical levels. In order to bring out these generic features, we have analysed a series of principles associated with complexity and systems theory in the context of theoretical physics. This analysis suggests an iterative technique to introduce complexity mechanisms in systems theory. First, one treats the complexity aspects to high or infinite order, using self-consistency arguments. To make such a treatment feasible it may be necessary to simplify the interactions. Having established the nature of the emergent states, one then couples these complex units or elements, employing the more accurate linear mechanisms common in systems dynamics software. This stepwise process can be continued until a stable or periodic solution appears.