By Luke Kemp
19 February 2019
Studying the demise of historic civilisations can tell us how much risk we face today, says collapse expert Luke Kemp. Worryingly, the signs are worsening.
Great civilisations are not murdered. Instead, they take their own lives.
This article is part of a new BBC Future series about the long view of humanity, which aims to stand back from the daily news cycle and widen the lens of our current place in time. Modern society is suffering from “temporal exhaustion”, the sociologist Elise Boulding once said. “If one is mentally out of breath all the time from dealing with the present, there is no energy left for imagining the future,” she wrote.
That’s why the Deep Civilisation season will explore what really matters in the broader arc of human history and what it means for us and our descendants.
So concluded the historian Arnold Toynbee in his 12-volume magnum opus A Study of History. It was an exploration of the rise and fall of 28 different civilisations.
He was right in some respects: civilisations are often responsible for their own decline. However, their self-destruction is usually assisted.
The Roman Empire, for example, was the victim of many ills including overexpansion, climatic change, environmental degradation and poor leadership. But it was also brought to its knees when Rome was sacked by the Visigoths in 410 and the Vandals in 455.
Collapse is often quick and greatness provides no immunity. The Roman Empire covered 4.4 million sq km (1.9 million sq miles) in 390. Five years later, it had plummeted to 2 million sq km (770,000 sq miles). By 476, the empire’s reach was zero.
Our deep past is marked by recurring failure. As part of my research at the Centre for the Study of Existential Risk at the University of Cambridge, I am attempting to find out why collapse occurs through a historical autopsy. What can the rise and fall of historic civilisations tell us about our own? What are the forces that precipitate or delay a collapse? And do we see similar patterns today?
The first way to look at past civilisations is to compare their longevity. This can be difficult, because there is no strict definition of civilisation, nor an overarching database of their births and deaths.
In the graphic below, I have compared the lifespan of various civilisations, which I define as a society with agriculture, multiple cities, military dominance in its geographical region and a continuous political structure. Given this definition, all empires are civilisations, but not all civilisations are empires. The data is drawn from two studies on the growth and decline of empires (for 3000-600BC and 600BC-600), and an informal, crowd-sourced survey of ancient civilisations (which I have amended).
Click/pinch to enlarge. Here’s the full list of the civilisations displayed above. (Credit: Nigel Hawtin)
Collapse can be defined as a rapid and enduring loss of population, identity and socio-economic complexity. Public services crumble and disorder ensues as government loses control of its monopoly on violence.
Virtually all past civilisations have faced this fate. Some recovered or transformed, such as the Chinese and Egyptian. Other collapses were permanent, as was the case of Easter Island. Sometimes the cities at the epicentre of collapse are revived, as was the case with Rome. In other cases, such as the Mayan ruins, they are left abandoned as a mausoleum for future tourists.
What can this tell us about the future of global modern civilisation? Are the lessons of agrarian empires applicable to our post-18th Century period of industrial capitalism?
Collapse may be a normal phenomenon for civilisations, regardless of their size and technological stage
I would argue that they are. Societies of the past and present are just complex systems composed of people and technology. The theory of “normal accidents” suggests that complex technological systems regularly give way to failure. So collapse may be a normal phenomenon for civilisations, regardless of their size and stage.
We may be more technologically advanced now. But this gives little ground to believe that we are immune to the threats that undid our ancestors. Our newfound technological abilities even bring new, unprecedented challenges to the mix.
And while our scale may now be global, collapse appears to happen to both sprawling empires and fledgling kingdoms alike. There is no reason to believe that greater size is armour against societal dissolution. Our tightly-coupled, globalised economic system is, if anything, more likely to make crisis spread.
If the fate of previous civilisations can be a roadmap to our future, what does it say? One method is to examine the trends that preceded historic collapses and see how they are unfolding today.
While there is no single accepted theory for why collapses happen, historians, anthropologists and others have proposed various explanations, including: