March 17, 2010
I’ve just completed my first draft of an academic paper I’ve been working on entitled: “Punctuated Equilibria” as Emergence: An Interdisciplinary Approach to Change in Social Systems.
Readers of either of my two blogs will know that I think recent advances in thinking about complex adaptive systems can offer a tremendous amount to disciplines outside the traditional ones of physics and systems biology.
In this paper, I propose that Stephen Jay Gould’s famous theory of punctuated equilibria may be seen as a special case of emergence in complex adaptive systems, and the same approach can be used to gain a better understanding of major changes in human social systems: in pre-history, in historical times, and in our present day.
Here’s the abstract to the paper:
The theory of “punctuated equilibria” proposed by Eldredge and Gould is conceived as a special case applied to the field of paleobiology of the more general dynamic of emergence in self-organized adaptive systems. “Punctuated equilibria” has been sporadically applied as a descriptor of change in social systems, and elsewhere the underlying methodological linkage to emergence has been noted. However, it is proposed that a more formal application of emergence theory to changes in human social systems offers the potential for new insight. The distinction between “epistemological” and “ontological” emergence is discussed and the key concept of “reciprocal causality” introduced. Documented examples of ontological emergence in animal and ecological self-organization are reviewed. A theoretical framework is then applied, for illustrative purposes, to three cases of pre-historical and historical emergence in human social systems – language, agriculture and the scientific/industrial revolution. The framework is then applied to potential phase transitions in the current human system.
Here’s a link to a pdf version of the working draft of the paper. Anyone with an academic interest in this subject is invited to read and comment, either in the comments section below or by e-mail.
March 4, 2010
By Norman Yoffee.
New York: Cambridge University Press.
Casual readers beware! The “myths” of the archaic state in Norman Yoffee’s title are not the original myths of the early civilizations. Rather, Yoffee is referring to academic “myths” of traditional scholarship that his book aims to debunk. This means that his work is targeted mainly for those already steeped in the theory of anthropology rather than those wanting to learn about the ancient civilizations themselves.
That said, there’s plenty of intriguing material about daily life in Mesopotamia in particular that will reward careful reading. Yoffee’s approach emphasizes the dynamics of social roles and power dynamics in early civilizations, and as such he offers unusually detailed analyses of real world activities. For example, a particularly memorable section is entitled “Imagining Sex in an Early State”, and describes how the Assyrian word for prostitute, kezertu, was derived from the verb kezeru, which means “to curl the hair.”
Fascinating as that is, the most notable aspect of Yoffee’s book for me is his application of complexity theory to understanding the major transitions in early human history. Theories of complexity and self-organization are gaining increasing acceptance in biological specializations such as collective animal behavior or cellular dynamics, but it’s still rare for these approaches to be applied in disciplines that deal with the collective behavior of that rather strange animal called “the human.”
Yoffee first lays his theoretical foundation, describing a complex adaptive system as one that “cannot be reduced to the ‘sum of its parts’ because the action of some parts is always affecting the action of other parts, so that equilibrium of the entire system is never reached or maintained for very long.” He then clenches his proverbial teeth and takes the plunge, stating:
I mean to show … that not only are ancient states and civilizations complex systems …, but so are all human societies playgrounds for social negotiation and for the empowerment of the few, and their parts remain far from some equilibrium with each other and their environment… the task is not to ask whether a society is complex but how it is complex…
On this basis, Yoffee borrows some of the “concepts and terminology from research on ‘complex adaptive systems” to show how minor perturbations in a social organization can occasionally lead to extremely rapid and dramatic change.
In taking this approach, Yoffee becomes a pioneer in an intellectual movement that I believe will have sweeping consequences in the years to come. He’s not the first prominent anthropologist to undertake this intellectual journey. For example, twenty years ago, Gregory Possehl, in writing about the Harappan civilization, made the following observation:
Thinking systematically, we see that virtually all parts (institutions and individuals) of the vast interconnected, largely seamless web of sociocultural systems are surely involved in the dynamic of change, as agents of both effect and affect… [N]either our anthropological vocabulary nor our discipline’s conceptual apparatus facilitates expression of the complex, subtle notion involved here… Once change has started there occurs a kind of “domino effect,” … a complex set of positive and negative “feedback” exchanges that sustain the process…
However, while Possehl identified the same dynamic, he seemed well aware that he lacked the theoretical language to be able to apply it systematically to his subject. Yoffee, by contrast, explicitly describes the rapid evolution of city-states in the late 3000s-early 2000s BC as a “phase transition” from “one state of being to another,” and compares it to the classic example from physics of hot water transitioning to boiling only at the point where it’s heated to 100˚ Celsius.
In another section, Yoffee uses the complexity theory concept of “emergent properties” to delve into the dynamics that transformed hunter-gatherers to settled farmers. In this case, he goes beyond the usual analysis of how humans transformed crops and animals by considering the reciprocal effects of domesticated plants on human activity. He describes how people needed to spend an increasing amount of time and energy looking after the crops and animals that were gradually becoming tamer and less able to compete in the wild, so that “people also become dependent on domesticants,” their movement restricted by the requirement to tend their new assets.
I believe that Yoffee’s pioneering approach is taking anthropology in a fertile direction, but I think these are only the first, tentative steps in a long journey. I wonder if a breakthrough available to Yoffee and others in the field might be to join the concept of “punctuated equilibria” proposed by Niles Eldredge and Stephen Jay Gould with the “phase transition” dynamics of complexity theory. Yoffee mentions Gould in passing in his book, but only in reference to the work of another anthropologist.
In their foundational 1977 paper on punctuated equilibria in speciation, Gould and Eldredge suggested that “a general theory of punctuational change is broadly, though by no means exclusively, valid throughout biology.” Just as complexity theory is now increasingly being applied beyond biology to the arena of social sciences, the same case might be made for punctuated equilibria. In fact, an argument could be made that Gould & Eldredge’s application of their theory to evolutionary speciation may be one particular applied case of the more general rule of emergence in complex dynamic systems.
Gould himself, a few years later, speculated on some of the wider implications of his theory, stating:
In the largest sense, this debate is but one small aspect of a broader discussion about the nature of change: Is our world … primarily one of constant change (with structure as a mere incarnation of the moment), or is structure primary and constraining, with change as a “difficult” phenomenon, usually accomplished rapidly when a stable structure is stressed beyond its buffering capacity to resist and absorb.
Here, by way of comparison, is Yoffee’s summary description of the sudden shift from village communities to city-state in ancient Mesopotamia, which seems to fit Gould’s characterization:
In Mesopotamia, villages that were centers of production and exchange, that were located on trade routes and/or rivers, that lay near great agricultural land, seats of temples and regional worship, and that were defensible locations from attacks by neighbors – for hundreds or thousands of years – suddenly became cities, as people from the countryside increasingly moved into them.
The concept of punctuated equilibria has already been applied by leading thinkers in other disciplines within the social sciences. For example, Richard Klein refers to it in characterizing his view of the pattern of human evolution; Quentin Atkinson et. al. see it as a model for the evolution and divergence of languages; and Joel Mokyr sees it as a “paradigm for technological history” in analyzing the phenomenon of the Industrial Revolution.
At first glance, the very term “punctuated equilibrium” seems incompatible with the general rule of complex dynamics systems existing “far from equilibrium.” However, I believe this may be a problem with Gould & Eldredge’s choice of terminology rather than the underlying dynamics they are describing. If you consider the paradigmatic example of water coming to the boil, it may appear at equilibrium at the surface, but underneath there is an increasing flow of currents as the water gets ever closer to a phase transition. Similarly, in Yoffee’s example of Mesopotamian urbanization, the forces affecting village dynamics would have been slowly building even while, at the surface, the village appeared stable. Perhaps a more apt name for Gould & Eldredge’s dynamic might be “punctuated continuum,” suggesting a relatively stable, gradually changing continuum suddenly entering a phase transition of rapid transformation.
There is some theoretical underpinning for this linkage of the two concepts in the writings of Per Bak and Kim Sneppen, the two physicists who first coined the term “self-organized criticality.” In two different papers they write about the two sets of phenomena as one dynamic:
The model self-organizes into a critical steady state with intermittent coevolutionary avalanches of all size; i.e. it exhibits ‘punctuated equilibrium’ behavior… this behavior indicates that the ecology of interacting species has evolved to a self-organized critical state…
Gould and Eldredge have coined the term punctuated equilibrium to describe the intermittent behavior of the evolution of single species.
The implications of this approach in analyzing the major changes in early human society are widespread. Once you accept, as Yoffee has, that “the task is not to ask whether a society is complex but how it is complex,” then there is a profound impact on methodology. Instead of trying to identify a major cause or causes for a phase transition, the focus shifts to understanding how the different factors interacted with each other, and perhaps even more consequentially, how the larger social pattern then effected downward causation on the original factors, thus leading to the “reciprocal causality” characteristic of true emergence.
Thompson & Varela, two leading theoreticians in the study of complex systems, describe this self-organizing confluence of both “upward” and “downward” causation:
Emergence through self-organization has two directions. First, there is local-to-global determination or ‘upward causation’, as a result of which novel processes emerge that have their own features, lifetimes and domains of interaction. Second, there is global-to-local determination, often called ‘downward causation’, whereby global characteristics of a system govern or constrain local interactions. This aspect of emergence is less frequently discussed, but has long been noted by researchers in the field of complex dynamical systems. It is central to some views about consciousness and the brain…
Let us hope that Yoffee’s pioneering efforts in this area have begun their own pattern of emergence, whereby his approach, along with others, initiate the beginnings of some “downward causation” in their field, leading perhaps to a “phase transition” in methodological approaches throughout the social sciences.
 Possehl, G. L. (1990). “Revolution in the Urban Revolution: The Emergence of Indus Urbanization.” Annual Review of Anthropology, 19, 261-282.
 Gould, S. J., and Eldredge, N. (1977). “Puctuated Equilibria: The Tempo and Mode of Evolution Reconsidered.” Paleobiology, 3(2 [Spring 1977]), 115-151.
 Gould, S. J. (1982). “Darwinism and the Expansion of Evolutionary Theory.” Science, 216(4544:April 23), 380-387.
 Klein, R. G. (2000). “Archeology and the Evolution of Human Behavior.” Evolutionary Anthropology, 9(1), 17-36.
 Atkinson, Q. D., et. al. (2008). “Languages Evolve in Punctuational Bursts.” Science, 588.
 Mokyr, J. (1990). The Lever of Riches: Technological Creativity and Economic Progress, New York: Oxford University Press.
 Bak, P., and Sneppen, K. (1993). “Punctuated Equilibrium and Criticality in a Simple Model of Evolution.” Physical Review Letters, 71(24), 4083-4086. Also: Sneppen, K., Bak, P., Flyvbjerg, H., and Jensen, M. H. (1995). “Evolution as a self-organized critical phenomenon.” PNAS, 92(May 1995), 5209-5213.
 Thompson, E., and Varela, F. J. (2001). “Radical embodiment: neural dynamics and consciousness.” Trends in Cognitive Sciences, 5(10), 418-425.