How Civilizations Fall: A Theory of Catabolic Collapse

Introduction

  • The collapse of human societies is a poorly understood phenomenon
    • Most proposed explanations fail to describe causative mechanisms
    • Rely on ad-hoc hypotheses reliant upon the specifics of the civilization
    • Make essentially mystical claims (like comparing civilizations to biological organisms)
  • Tainter (1988) proposed a general theory of collapse
    • Complex societies break down when increasing complexity results in negative marginal returns
    • Decrease in sociopolitical complexity yields net benefits to society
    • While this theory has strengths, it does not model the temporal aspect of civilizational breakdown
    • Tainter talks about breakdowns occuring over a period of decades, when actual civilizations often take centuries to collapse
    • An alternative model based on perspectives from human ecology offers a more effective way to understand the collapse process
  • Theory of catabolic collapse
    • Models collapse as a self-reinforcing cycle of decline
    • Driven by interactions between
      • Resources
      • Capital production
      • Waste

The Human Ecology of Collapse

  • At the highest level of abstraction, each human society involves 4 elements
    • Resources
      • Naturally ocurring factors in the environment
      • Resources that have not yet been extracted and incorporate into society’s flows of energy and material
      • Examples:
        • Natural resources
        • Soil fertility
        • Human resources – people who could work but are not yet working
        • Scientific discoveries which have not yet been made
    • Capital
      • Everything that has been incorporated society’s flow of energy and materials, but is capable of future use
      • Tools, buildings, materials, productive farmland
      • Also includes social capital such as economic systems and social organization
    • Waste
      • All factors that have been completely incorporated into society’s flows of energy and material, but which are no longer capable of future use
      • Discarded resources
      • Worn out tools
      • Laborers at the end of their lives
      • Information that is garbled or lost
    • Production
      • Process by which existing capital and resources are converted into new capital and waste
      • Resources and capital can, to some extent, be substituted for one another, but the substitution is not 1:1 and the conversion is nonlinear
      • As the use of resources approaches zero, exponential amounts of capital are required to maintain production
  • The maintenance of a steady state requires the rate of production of new capital to equal the waste from production and non-production processes
  • Societies which expand produce more capital than is required to maintain existing stocks
  • This becomes a self-reinforcing cycle – an anabolic cycle
    • Increases in capital stock drive greater utilization of resources
    • This leads to even more capital being formed, which perpetuates the cycle
  • Anabolic cycles are limited by two factors
    • Resource depletion
      • All resoures have a replenishment rate and a depletion rate
      • Resources that become depleted must be replaced by capital to maintain production
      • Because of the nonlinear substitutability of capital and resources, an exponential amount of new capital is required to replace the depleted resource
    • Inherent relation between capital and waste
      • As capital stocks rise, the amount of production required to maintain capital stocks also rises
      • This results in increased waste, which makes producing new capital more difficult
  • When an anabolic cycle ends, a society faces a choice between two alternatives
    • Move to a steady state where new capital formation is equal to maintenance production and depletion rate is equal to replenishment rate
      • Requires social controls to keep capital stocks down to a level where maintenance costs can be met by current production
      • Requires difficult collective choices, but as long as resource availability remains stable, controls on capital production remain in place, and society escapes major exogenous shocks, this process can be maintained indefinitely
    • Take steps to prolong the anabolic cycle
      • Invent new technology
      • Military conquest
      • Since increasing production leads to increasing capital stocks, which inherently increases waste, this means that maintenance production must increase
      • Thus a society that attempts to prolong its anabolic cycle must increase its production at an ever increasing rate
  • If an attempt to maintain a steady state fails, society enters a contractionary phase, which takes one of two forms
    • Maintenance crisis
      • Occurs when society at or below replenishment rates
      • Capital that cannot be maintained turns into waste
      • Physical capital is destroyed or spoiled
      • Human populations decline in number
      • Large scale social organizations splinter into a larger number of more economical small scale social organizations
      • Information is forgotten or lost
      • However, because resources are not depleted, maintenance crises tend to be self-limiting
      • At some point, the required rate of capital production falls below the actual rate of new capital production and civilization resumes
    • Depletion crisis
      • A resource that uses resources beyond their replenishment rate enters a catabolic cycle
      • Key features of maintenance crises are magnified by resource depletion
      • Resource depletion saps a civilization of its ability to produce new capital, just as maintenance requires every increasing levels of capital production
      • This results in a catabolic cycle, where new capital production remains below the capital production required for maintenance, even as both values decline
      • Catabolic cycles can occur in maintenance crises, but they tend to be self-limiting
      • In a depletion crisis, catabolic cycles can accelerate into catabolic collapse, where most of a civilization’s production is converted into waste and new production approaches zero

Testing The Model

  • The two types of crisis (maintenance crisis and depletion crisis) are the ideal ends of a scale
  • Most actual civilizational collapse take place somewhere in between the ideal ends
  • Maintenance crises
    • Kachin socities of Burma – cycle from relatively centralized to decentralized forms without much loss of physical, human or information capital
    • Historical China
      • Repeated cycles of unifications and breakup
      • The sustainability of traditional Chinese agriculture meant that replenishment was high and any collapse was self-limiting
  • Catabolic collapse
    • Western Roman Empire
      • The Mediterranean civilization at the core of the empire was based upon readily replenished resources
      • However the Empire was the result of military expansionism and easily depleted resources
      • After Rome’s initial conquests, the territories which remained were either resource poor or were capable of defending themselves
      • This led to a depletion crisis as Rome was no longer able to acquire new resources, leading to a lower replenishment rate
      • The collapse of Rome has a instructive feature which further supports the model
        • In AD 297 Diocletian divided the Empire into Eastern and Western halves
        • With the death of Theodosius I, in AD 395, there was no further cooperation between the two halves of the empire
        • The Western Roman Empire produced only one-third the revenue of the Eastern Roman Empire, however, it had much more territory to defend
        • The split allowed the Eastern Roman Empire to convert large amounts of high-maintenance capital into waste, which enabled it to surive for nearly a millenium longer as the Byzantine Empire
    • Lowland Classic Maya
      • Mayan population and agriculture grew beyond a level that could be supported by the nutrient poor soils of the Lower Yucatan
      • Mayan polities created massive building projects which did not contribute to further production
      • The result was a “rolling collapse” over two centuries, in which urban centers were abandoned
      • The Lowland Classic Maya collapse was preceded by two other similar breakdowns
      • It’s unclear whether they were maintenance crises preceding the final collapse or whether there’s some other explanation
  • Features of long-lasting societies often have measures to reduce the growth of capital
    • Aspects of the potlatch economy
    • Ritual deposition of prestige metalwork by bronze and iron-age societies of Western Europe

Conclusion: Collapse As A Succession Process

  • Even within the social sciences, the process by which complex socities give way to smaller and simpler societies has been described with the language of literary tragedy
  • This is understandable, given the destruction that is often involved, but it confuses a description of the facts with a value judgment
  • A less problematic approach is to use the language of ecological succession
  • Succession describes the process by which an area not yet occupied by life is colonized by a series of seres or biotic complexes, eventually culminating in a stable, self-perpetuating climax
    • Earlier seres tend to use r-selected reproduction strategies, maximizing expansion at the expense of efficiency
    • Later seres tend to use k-selected reproductive strategies, maximizing efficiency even if it leads to lower rate of reproduction
  • While human societies cannot directly be compared to biological species, there are certain similarities between human societies and biotic seres
  • However, human societies can switch between r-selection and k-selection in a way that biological species cannot