Collapse is a Recurrent Phenomenon in Societies

The Roman Empire's dramatic collapse (followed by many centuries of population decline, economic deterioration, intellectual regression, and the disappearance of literacy) is well known, but it was not the rst rise-and-collapse cycle in Europe. Prior to the rise of Classical Greco- Roman civilization, both the Minoan and Mycenaean Civilizations had each risen, reached very advanced levels of civilization, and then collapsed virtually completely [Morris, 2006; Redman, 1999]. The history of Mes...

 The HANDY Model is Based On Predator-Prey Cycles

As indicated above, Human And Nature DYnamics (HANDY) was originally built based on the predator-prey model. We can think of the human population as the predator", while nature (the natural resources of the surrounding environment) can be taken as the prey", depleted by humans. In animal models, carrying capacity is an upper ceiling on long-term population. When the population surpasses the carrying capacity, mechanisms such as starvation or migration bring the population back down. However, ...

 Two Kinds of Societal Collapse

Running the model in dierent scenarios produces two kinds of collapses, either due to scarcity of labor (following an inequality-induced famine) or due to scarcity of Nature (depletion of natural resources). We categorize the former case as a Type-L (Disappearance of Labor) Collapse and the latter as a Type-N collapse (Exhaustion of Nature). In a Type-L collapse, growth of the Elite Population strains availability of resources for the Commoners. This causes decline of the Commoner Population ...

 Insulation of Elites Compounds Societal Collapse

The scenarios most closely reflecting the reality of our world today are found in the third group of experiments (see the scenarios for an unequal society in section 5.3), where we introduced economic stratication. Under such conditions, we nd that collapse is dicult to avoid, which helps to explain why economic stratication is one of the elements consistently found in past collapsed societies. Importantly, in the rst of these unequal society scenarios, 5.3.1, the solution appears to be on a ...