Think of the decline of ancient Rome, which took centuries; nobody knows why it declined; we have more explanations than authors. Because of the great influence of chance in all aspects of society, whose behavior is unknowable and, hence, unpredictable—manageable only up to some point, after which further developments grow out of hand. Why the reason for a crash such as the decline of Rome is also unknowable, and why its crash was unmanageable, is that people usually look at only one process in isolation, such as the invasion of the Gothic tribes or the general poisoning of people by lead in the water pipes. In many cases, however, a disaster is triggered by the coinciding of a number of different events or processes, not by a single event or process. Therefore, as our numbers continue to grow exponentially, the size and complexity of society increases exponentially relative to those numbers. Consequently, the predictability of a particular crash developing from the occurrence of a certain combination of chance events or processes decreases.
Moreover, because many factors can be interdependent, a crash in one sector pulls others in its wake, making it a general crash in no time and also making it more difficult to manipulate or manage. Crashes of our socioeconomic system will therefore become more frequent and less easy to control.
I think that the collapse of the present human population, its numbers and quality of life, is likely, and also that the most humane way to weather this period is to design a strategy and follow it ourselves rather than sit back and wait complacently. Unfortunately, the time for old customs and cultural traditions or of long-held beliefs and trusts is over. As the latest calculations from 1992 by Meadows and colleagues in “Beyond the Limits“ showed, our world can collapse, and this can happen even before any resource has definitively been depleted; collapse may come at any time and out of nowhere. It’s an inevitable, unavoidable result of the behavior of an oversized, complex, nonlinear system in which interdependent chance processes dominate.