Sander van der Leeuw has had a distinguished transatlantic career in the management of comprehensive archaeological projects (most notably, ARCHAEOMEDES, in the northern Mediterranean), his development of Arizona State University's School of Human Evolution and Social Change, and his study of complex systems at the Santa Fe Institute.
This book is a compendium of his understanding of social institutions as complex systems. It is divided into three sections. Part I introduces key building blocks, including a history of the role of science in society and the necessity of both a long-term perspective and a complex adaptive systems (CAS) approach. Part II introduces his theoretical perspectives—most importantly, his choice of information and communications technology (ICT) as a central driver in human evolution and the roles of novelty, invention, and change in human societies. Part III examines the influence of ICT and what might be done to address the looming global systemic failure.
In keeping with the holistic framing of CAS, it is easy to agree with many of the author's positions: the role of past choices as the initial conditions of future dynamics; the enduring social context of science; and the importance of systemic diversity, fast and slow variables, and unintended consequences.
What is less easy to reconcile is the author's preference for an essentially reductionist argument, placing ICT as the principal driver of human evolution. This is particularly surprising because anatomically modern humans (Homo sapiens sapiens—perhaps also Homo sapiens neanderthalensis, presumably with cognitive skills equivalent to those of anatomically modern humans) navigated harsh Pleistocene environments for thousands of years. Most archaeological approaches to the history of humanity routinely place early societies in context, tracing environmental and social change from the later Pleistocene to more clement and stable Holocene conditions, when resources became more diverse and populations grew.
The elimination of the roles of climate, collaborative action, and mobility in human evolution undermines the importance of CAS and necessitates a position that contains several unexamined assumptions. An example is the use of group size as an indicator of the degree of innovation. The author argues that innovation does not spread between isolated late Pleistocene “forager” [sic] groups, even though the geography of blade technology, the long history of human migrations (across continents, mountain ranges, bodies of water), and anatomical modernity would suggest otherwise.
The archaeological record demonstrates that small human groups, operating in flexible teams, could circumvent “the limits of the human brain's short-term working memory” (p. 59). Recent finds of rock art, in the Amazon and elsewhere, attest to the great time depth of collective memory. Paleobotanical and biophysical evidence from later Pleistocene sites suggests healing traditions through the use of medicinal plants and surgery. Changing landscapes, vegetation, and prey would have stimulated increased mobility and the spread of innovation many millennia before the first towns came into existence.
Another assumption is that a “natural” increase in competition and hierarchical leadership led to towns, cities, and states. Recent archaeological, bioarchaeological, and other research (e.g., Elinor Ostrom and colleagues’ compilation of ethnographic examples) reveals societies with successful distributed leadership and community-wide governance in small groups with economies based on subsistence as well as in states, regions, and urban agglomerations (e.g., Callejón de Huaylas / Recuay, central Thailand, Mimbres, Tiwanaku, Marroquíes) and even empires (Xianbei, Ghengis Kahn's Mongols). This recent understanding should encourage archaeologists to examine circumstances in which collaborative and ranked formations appear and disappear across time and space (Becker and Juengst, American Anthropologist 122:891–940, 2020).
Van der Leeuw's preferred branch of CAS advocates the central importance of hierarchy developed by cognitive psychologist Herbert Simon and colleagues. A different CAS approach, based on study of the human brain by cybernetician Warren McCulloch, may be found in the work of anthropologists and MIT mathematicians, whose heterarchical architecture of computer design is found in Random Access Memory (RAM). The latter perspective focuses on the dialectical relations among heterarchical (distributed authority, multiple components) and hierarchical (ranked authority) organization operating in various combinations at different spatial and temporal scales. A source of diversity and a motor of change, more flexible organization blends individual skills and shifting organizational responsibilities to offer societies of any size a source of symmetry breaking and innovation.
However one might view complexity in human societies, van der Leeuw's Part III offers a masterful, stand-alone, fine-grained analysis of the current global-scale multicrisis. He drives home the fundamental need to adopt a CAS approach to simultaneous and hyperconnected crises: a global pandemic, social upheaval, a deteriorating climate, and the widespread unintended consequences of ICT. As the information-processing capacity of Western society reaches a tipping point, the attack on the U.S. Congress and Capitol in January 2021—driven by the megaphone of social media—is anticipated in this section.
The living world makes its appearance in the form of the loss of environmental knowledge, rapidly changing conditions, and the unanticipated results of previous choices. Down come cities and governments, and up will come smaller communities with multidimensional “value spaces” (in contrast with the current dominant value of wealth). There are many good suggestions in this section, but the fundamental point is that it is both necessary and possible to think about change as an opportunity, in the guise of a global pandemic or a clever idea.
