Societies as Complex Systems
May 20th, 2006The theory of complex systems has captured the imagination of many people who think about the past and future of societies. The notion that societies may be thought of as Complex Adaptive Systems (CAS) is certainly compelling. CAS are made up of many interacting elements, each following its own local behavioral rules, which includes an ability to learn. A frequently-cited feature of CAS that is relevant to social dynamics is that CAS can shift abruptly from one regime to another. However, writing as a policy analyst who studies socioeconomic scenarios, this feature does not provide much guidance when thinking about societies. Instead, I would propose that the most important lessons to learn from CAS are that structure is not fundamental, and is inherently fuzzy.
Some very brief background:
In CAS, structure arises from local dynamics, so the structure is not fundamental – the local dynamical rules are. When the system settles down into a steady pattern, it moves rapidly between a large number of qualitatively similar states. Having a large number of states helps to stabilize the system and permits it to evolve, so fluctuations are not only unavoidable, they are crucial for the viability of the system. Hence structure is not fundamental in CAS, and is inherently fuzzy.
Since structure is not fundamental, CAS have one structure rather than another partly for historical reasons and partly because of additional factors that influence the system. Any structure consistent with the underlying dynamics and the prevailing additional factors is possible. As the influencing factors change, CAS can exhibit abrupt shifts from one qualitative regime to another. (In the case of societies or communities, an example of this would be a shift from extensive to intensive cultivation as population density increased.)
There are several reasons why the “abrupt change” feature of CAS is less compelling than the more pedestrian idea that structure is not fundamental, and fuzzy. First, in many cases, the assumption that the structure is fixed and unchanging is an excellent approximation. While it is important to bear in mind that the structure can change (because it is not fundamental), it is nevertheless analytically useful. Second, the meaning of “abrupt” depends on the relevant time-scales. In the case of societies, an “abrupt” change may take more than one generation to play itself out. Third, the particular parameter value that might trigger a change is unknown for social systems. Without knowing where the threshold lies and how long the change can take to occur, the “abrupt change” picture is not analytically fruitful. Fourth, much of what people experience in their lives as wrenching change is actually within the bounds of normal fluctuation. It is common enough to suppose that some event has “changed everything,” and in some sense that may be true, but not in the sense that society has shifted from one qualitatively distinct state to another. Many social structures are remarkably stable. Fifth, and finally, it is very difficult to say what structures are compatible with the underlying dynamics of the interacting parts of society, because these are very imperfectly understood. For all these reasons, the idea that societies and communities, as CAS, may exhibit abrupt changes in structure is not very informative for practical analytical work.
Starting instead with the idea that structure is not fundamental and is inherently fuzzy can, on the other hand, inform practical work. It leads to three concrete recommendations for the analyst:
- Do not take existing social structures for granted.
- Look for historical examples of change in social structure as part of your analysis.
- Accept variability as both inescapable and necessary for the viability of societies and communities and incorporate it into your analysis.
These observations are less dramatic, but perhaps more useful, than the picture of CAS leaping from one state to another.
