Work on Structural-Demographic Theory

A structural-demographic analysis of long-term changes in American well-being, elite competition, state capacity, and political instability.

Structural-demographic theory was developed by Goldstone and others (Nefedov 2003, Turchin 2003, Korotayev et al. 2011) as a tool for understanding long-term social pressures that lead to revolutions, civil wars, and other major outbreaks of socio-political instability.

Une enquête sur la thèse de la surproduction d’élites, son usage dans le débat français et les objections de sociologues. Peter Turchin y précise son analyse des inégalités et des crises sociales, en s’opposant à la restriction de l’accès à l’université.

Dans cet éditorial, Peggy Sastre mobilise les travaux de Peter Turchin pour analyser les violences à Paris : appauvrissement des classes populaires, concurrence entre élites et affaiblissement des capacités de l’État.

Coin Hoards Give Us a Quantitative Proxy for Instability Dynamics

A blog post I wrote in 2013

Complex Dynamics of Political Instability

A Cross-National Comparison

The theory advocates structural-demographic theory (SDT), which explains how large societies organized as nation-states periodically experience political instability due to polarization, social divisions, and institutional dysfunction.…

Le nouveau maire socialiste de la ville-monde porte aussi la colère des citoyens éduqués frustrés de ne pas accéder à l’élite.

Dr. Peter Turchin is Emeritus Professor at the University of Connecticut in the departments of ecology and evolutionary biology, anthropology, and mathematics. He is a project leader at the Complexity Science Hub Vienna and a research associate at the School of Anthropology at the University of Oxford.…

La victoria del candidato socialista en Nueva York se vio impulsada en gran medida por los precarios con titulación: jóvenes con título universitario o superior que ganan lo justo para sobrevivir. La principal noticia política de la semana es la victoria de Zohran Mamdani en las elecciones a la alcaldía de Nueva York.…

Why do civilizations rise, prosper, and then collapse? Here's what the math tells us. In this episode, we sit down with Peter Turchin, complexity scientist and founder of the field of cliodynamics, which uses data and mathematical models to study the long-term cycles of history.…

An analysis of historical crises over the past 2,000 years offers lessons for avoiding the end times. Anti-establishment parties and politicians are surging in Western Europe and Japan. In the United States, the MAGA movement, led by President Donald Trump, has seized power.…

Is it possible to forecast the dynamics of societal resilience and its obverse, sociopolitical unrest or even breakdown? This is the goal of Structural-Demographic Theory (SDT), which integrates mechanism-based models with data and focuses on the dynamics of structural drivers for instability over the long-term (thus, requiring a historical approach). Several recent studies utilizing the SDT framework have proven adept at predicting (or “retrodicting”) sociopolitical instability in c.20 past societies. It was also used in 2010 to successfully forecast the outbreak of US instability for 10 years in the future (in 2020). This study applies the SDT to explore the dynamics of another contemporary society. Our aim is to empirically test SDT in a most rigorous way, using it to forecast future dynamics of sociopolitical instability in Japan. Our research questions are: (1) how accurately (if at all) does the SDT framework predict future levels of sociopolitical instability; (2) What are the relative contributions of possible drivers of instability, including those proposed by SDT, as well as other theories, in explaining instability levels; and (3) are there key ‘leverage points’ that might help mitigate the negative consequences of instability? This article explains how we develop quantitative indices for SDT drivers of instability: mass immiseration, elite overproduction, and state fiscal distress. We then construct a Political Stress Index to track the evolution of these pressures from the 1990s to the present and implement a multipath forecasting model to project future trends through 2050, using a variety of intervention (or non-intervention) scenarios. Our plan is to revisit these predictions ten years in the future with the goal of assessing their accuracy.

Delta Air Lines is having a good 2025, reporting strong second-quarter earnings and reinstating its April profit guidance, leading to a substantial stock bump (up roughly 16% from June to July).…

New York’s Democratic mayoral hopeful Zohran Mamdani taps into an energy mirrored in Corbynism: overqualified graduates who are pro-rent control, anti-Israel and agitating for change

Historians and social scientists have long been preoccupied with understanding and documenting periods of crisis. Such emphasis is only growing, and becoming more pressing, as the world continues to face a number of interrelated stressors in the form of irreversible climate change, major ecological shocks and disease outbreaks, eruptions of military violence, economic disruptions and deepening inequalities, political polarization and unrest, the rise of authoritarian and nationalist regimes. Crises in these domains are not new, but have been recurrent features of past societies. Although these periods have typically led to massive loss of life, the failure of critical institutions, and even complete societal collapse, there are instances in the historical record of societies managing to turn the tide of crisis even as violence and social turmoil grow. Here, we focus on four such cases of crises mitigated with structural reforms revealed from our previous historical analyses: early Republican Rome, mid-19th century England and Russia, USA during the the late 20th to early 21st centuries. Utilizing structural demographic theory as a lens to explore these cases, we seek to expose the pressures that built up leading to crisis and the early signs of violent confrontation revealed by these societies, as well as to examine the conditions and key decisions made in the midst of this unrest that allowed these societies to turn the tide and enact significant structural adaptations. Our findings have clear relevance to understanding and navigating similar crises in contemporary societies.