Peter Turchin

"The next decade is likely to be a period of growing instability... which could undermine... scientific progress..."

"Quantitative historical analysis reveals that complex human societies are affected by recurrent—and predictable—waves of political instability..."

"In the United States, we have stagnating or declining real wages, a growing gap between rich and poor, overproduction of young graduates with advanced degrees, and exploding public debt. These... social indicators are... related... dynamically. They... experienced turning points during the 1970s. Historically, such developments have served as leading indicators of looming political instability. ...50-year instability spikes occurred around 1870, 1920 and 1970, so another could be due around 2020."

"We are also entering a dip in the so-called ... This could mean that future recessions will be severe."

"All these cycles look set to peak in the years around 2020."

"We need to find ways to ameliorate the negative effects of globalization... Economic inequality, accompanied by burgeoning public debt, can be addressed by making tax rates more progressive."

"[W]e should not expand our system of higher education... An excess of young people with advanced degrees has been one of the chief causes of instability..."

"A group consisting entirely of self-regarding agents will never be able to cooperate. So cooperation is possible only if some agents are motivated by ‘extra-rational’ prosocial norms, including the norm of moralistic punishment."

"This article revisits the prediction, made in 2010, that the 2010–2020 decade would likely be a period of growing instability in the United States and Western Europe..."

"This prediction was based on a computational model that quantified in the USA such structural-demographic forces for instability as popular immiseration, intraelite competition, and state weakness prior to 2010."

"Using these trends as inputs, the model calculated and projected... the Political Stress Indicator, which in the past was strongly correlated with socio-political instability."

"Ortmans et al. Turchin P. 2010 conducted a similar structural-demographic study for the United Kingdom."

"Here we use the Cross-National Time-Series Data Archive for the US, UK, and several major Western European countries to assess these structural-demographic predictions."

"[S]uch measures of socio-political instability as anti-government demonstrations and riots increased dramatically during the 2010–2020 decade in all of these countries."

"How resilient are our societies to internal and external shocks?"

"Can we model and forecast the dynamics of social resilience and its opposite, social breakdown?"

"[G]rowing socio-political instability results from multiple interacting factors: economic, political, and cultural."

"(SDT) offers a... wholistic framework for investigating such... forces that... lead to revolutions, civil wars, and other major outbreaks of socio-political instability."

"SDT can be... an explicit computational model capable of forecasting future... social unrest and political violence in specific social systems."

"... was proposed by and further developed and tested by... investigators, including [S.] Nefedov, Turchin, [and] Korotayev et al."

"The SDT proposes that the causes of revolutions and major rebellions are... similar to processes that cause earthquakes. In both... it is useful to distinguish "pressures" (structural conditions, which build up slowly) from "triggers" (sudden releasing events, which immediately precede a social or geological eruption)."

"Specific triggers... are difficult, perhaps... impossible to predict. ...[S]tructural pressures build up slowly and more predictably, and are amenable to analysis and forecasting."

"Many triggering events... are ultimately caused by pent-up social pressures ...[i.e.,] the structural factors."

"The main focus of SDT... is on the structural pressures undermining social resilience."

"The theory represents complex human societies as systems with three main compartments (the general population, the elites, and the state) interacting with each other and with socio-political instability via a web of nonlinear feedbacks."

"The focus [is] on only these four structural components... [E]ach component has a number of attributes that change dynamically in response to... [the] other... variables."

"[T]he... forecast: “The next decade is likely to be a period of growing instability in the United States and western Europe” ...was not simply a projection of the current trend in social instability into the future. ...[T]he basis for this forecast was a quantitative model that took as inputs the major SD drivers for instability (immiseration, intraelite competition, and state (in)capacity) and translated them into the Political Stress Indicator (PSI)... strongly correlated with socio-political instability. The rising curve of the... PSI... suggests a growing future socio-political instability."

"SDT is a general theory that guides our understanding of political violence dynamics and social breakdown in all large-scale state-level societies."

"[W]e need to translate the general theory into a specific computational model tailored to the focal state. Over the past four decades this has been accomplished for... historical case-studies, ranging from Ancient empires to Early Modern states and nineteenth century’s revolutions and civil wars."

"[T]he theory has been applied to two contemporary societies. The first... is a structural-demographic model for the... USA... the basis for the 2010 prediction. The details... were published [by] Turchin and later expanded into a book-length treatment."

"was proposed 30 years ago. Although it was successively refined by other theorists... the theoretical core, and especially the emphasis on intra-elite competition and conflict as the most important driver of socio-political instability and state breakdown, remained constant. Over the past three decades, the theory was empirically tested by a growing number of researchers. Currently, there are detailed investigations of at least twenty crises... to test the predictions of the theory... [T]here are several dozen other less detailed examples. The... verdict is that.. predictions are well supported by data. ...[R]ival theories are not supported."

"[T]he "crude" Malthusian explanation, which connects popular immiseration to social breakdown, fails to account both for the start and end of the "Time of Troubles.""

"Many of the historical "Golden Ages" were... golden... only for the elites, whose high levels of consumption were based on low real wages and falling consumption levels of the great majority..."

"[W]hile declining living standards are often a contributing factor to... instability, reversing this trend does not end instability until elite overproduction is... reversed..."

"Making scientific predictions about the events that happened, but are not known to the authors of the theory, is a valid scientific approach in historical sciences, such as geology, astrophysics, evolutionary biology, and (history as science). It is sometimes referred to as "". ...[T]he primary way of testing theories in historical dynamics is retrodiction. But when mulitple successful tests using retrodiction (prediction about the past) are complemented with a few cases of prediction about the future, our degree of confidence in the theory is... enhanced."

"The SDT is not merely a theory for understanding why internal violence outbreaks develop and spike. By providing... understanding of the deep structural causes of socio-political instability and societal breakdown, SDT... gives us tools for adopting... reforms and policy interventions that can reverse these drivers of instability."

"[N]one of the fundamental structural-demographic drivers have been reversed, so far. Thus, the American social system continues to be very vulnerable to additional "quakes"."

"[D]isease outbreaks occur much more frequently during... crisis periods. Such epidemics historically have had a disproportionate effect on the less advantaged... and the Covid-19 pandemic was not an exception. ...[I]n terms of ... the pandemic... further worsened the well-being of large swaths of the American population... consequently, drove up the mass-mobilization potential. ...[G]overnmental dysfunction in dealing with the pandemic, coupled with intra-elite infighting, will likely further depress... trust in government institutions. Thus... the coronavirus has... further destabilize[d] the American ."

"[U]ntil the fundamental SD drivers for instability are reversed, there will be other triggering events... social turbulence may continue for years ahead."

"Historical data indicate that periods of enhanced instability and internal warfare usually extend for many years, with the median length... 10–15 years range."

"SDT gives us understanding of the deep structural causes of socio-political instability and... tools for adopting... reforms and policy interventions that can reverse these drivers... It remains to be seen whether our society will be able to use these tools."

"I began my career... as an ecologist... studying the population dynamics of beetles, butterflies, mice, and deer. ...I embraced the turn of the field to complexity science, which mixes computer modeling with Big Data analytics to answer such questions as... why many animal populations go through boom-and-bust cycles. By the late 1990s... I began to consider how the same... approach could be brought to the study of human societies. A quarter of a century later, my colleagues... and I have built out a flourishing field... (from Clio... the... Greek mythological muse of history, and dynamics, the science of change)..."

"[T]here are important recurring patterns... throughout... human history over the past ten thousand years."

"[C]omplex human societies at base and at some abstract level, are organized according to the same general principles."

"[M]y colleagues and I... focused on cycles of political integration and disintegration, particularly on state formation and state collapse."

"It became clear... through quantitative historical analysis that [throughout time] complex societies everywhere are affected by recurrent and, to a... degree, predictable waves of political instability, brought about by the same basic set of forces..."

"In 2010... Nature asked specialists... to look ten years into the future, and I made this case... judging from the pattern of US history, we were due for another sharp instability spike by the early 2020s. ...The book is my best attempt to explain this model... I make no claims of radical originality."

"[S]ocieties have arrived at this crossroads before, and though... most of the time...the road has led to great loss of life and societal breakdown, sometimes it has led to a far happier resolution ..."

"[W]hen a state... has stagnating or declining ... a growing gap between the rich and poor, overproduction of young graduates with advanced degrees, declining public trust, and exploding public debt... Historically such developments have served as leading indicators of political instability. In the United States all of these... started to take an ominous turn in the 1970s. The data pointed to... around 2020... a spike in political instability. And here we are."

"... uses the methods of data science, treating the historical record... as Big Data. It employs mathematical models to trace the intricate web of interactions..."