This website contains a living literature review on societal collapse https://florianjehn.github.io/Societal_Collapse Why we only talk about looming catastrophe - You are likely familiar with visions of doom. It is hard to avoid them these days. It’s scary, for sure. But are they helping? Looking at the world, they do not seem very effective. The USA left pretty much every environmental agreement you can think of, the EU always seems... Tue, 07 Apr 2026 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2026-04-07-captured_futures/ https://florianjehn.github.io/Societal_Collapse/2026-04-07-captured_futures/ A contribution to the United Nations Scientific Panel on the Effects of Nuclear War - This post was originally an invited contribution to the United Nations Independent Scientific Panel on the Effects of Nuclear War. I’m also sharing it here as an overview of the current state of nuclear winter research (+ related topics) and the open questions the field is grappling with. It was... Wed, 11 Feb 2026 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2026-02-11-nuclear_panel/ https://florianjehn.github.io/Societal_Collapse/2026-02-11-nuclear_panel/ Why crisis governance depends on democratic capacity - The proportion of the global population living under the spectrum of political systems classed as a democracy is near its all-time high, and stands (very approximately) around 4 billion, or around half of the global population. From a historical perspective, democracies have had quite the run over the last two... Mon, 02 Feb 2026 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2026-02-02-democracies_crisis/ https://florianjehn.github.io/Societal_Collapse/2026-02-02-democracies_crisis/ In Germany, at least - Recently, I visited a cold war bunker near Saarbrücken. It was a test bunker for West Germany, where they could try out all their new, fancy ideas on how to make the best bunker. To keep it secret, they build it in parallel to a new highway and it is... Sun, 18 Jan 2026 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2026-01-18-german_bunker/ https://florianjehn.github.io/Societal_Collapse/2026-01-18-german_bunker/ Supply and demand after global catastrophes - To better understand societal collapse we not only must examine the factors that could lead to collapse, but also what might happen during and after collapse. One crucial thing here is economics. What are the direct effects of collapse on an economy? How would prices change? Would trade continue? All... Wed, 07 Jan 2026 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2026-01-07-endtime_economics/ https://florianjehn.github.io/Societal_Collapse/2026-01-07-endtime_economics/ An overview of actors - Existential risk is not something static which lives outside of humanity. It is something humans shape. This can be directly, such as things that are created or deployed by humans like nuclear weapons. Or it can be indirectly, like whether or not humans have sufficiently prepared our infrastructure for major... Sat, 29 Nov 2025 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2025-11-29-risk_actors/ https://florianjehn.github.io/Societal_Collapse/2025-11-29-risk_actors/ A question of optimism - As long as we are not in the year 2100, we will not know exactly what path humanity will have taken when it comes to climate change in this century. But we can at least make educated guesses about the trajectory we are on. Given this, it seems that a... Mon, 03 Nov 2025 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2025-11-03-climate_focus/ https://florianjehn.github.io/Societal_Collapse/2025-11-03-climate_focus/ How vulnerable are we to the next Carrington Event? - Space weather often comes up as a topic when discussing what environmental hazards might lead to societal collapse or at least a massive societal disruption. The main idea here is that geomagnetic storms coming from the Sun create failures in the electrical grid so large that they cannot be repaired... Sun, 26 Oct 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-10-26-geomagnetic/ https://florianjehn.github.io/Societal_Collapse/2025-10-26-geomagnetic/ Structural demographic theory and the United States - Life feels more rough, because it is. At least this is what I took as one of the main messages from Peter Turchin’s book “End Times: Elites, Counter-Elites, and the Path of Political Disintegration”. In it Turchin takes us on a grand tour of his structural demographic theory and how... Wed, 03 Sep 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-09-03-End_Times/ https://florianjehn.github.io/Societal_Collapse/2025-09-03-End_Times/ How dominance hierarchies doom societies - When we study societal collapse, we typically examine it through the lens of elites. Using the records and remains left by emperors, nobles, and the literate classes who had the most to lose when their world ended. But what if we’ve been asking the wrong question all along? After years... Tue, 05 Aug 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-08-05-Goliath/ https://florianjehn.github.io/Societal_Collapse/2025-08-05-Goliath/ Climate change, nuclear winter, and stratospheric aerosol injections - Life on Earth depends on a stable climate. Both the biosphere and our global society are calibrated to a narrow band of habitability. The global temperature is governed by a lot of interacting systems, but it mostly boils down to how much energy from the Sun reaches the planet’s surface... Fri, 30 May 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-05-30-global_thermostat/ https://florianjehn.github.io/Societal_Collapse/2025-05-30-global_thermostat/ A list of lists of large catastrophes - For this post I aim to essentially create a little repository of catastrophic risk lists, so other people can find those more easily and get an overview of how groups of experts with different backgrounds categorize and evaluate risks. The motivation behind both this post and the articles I will... Fri, 25 Apr 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-04-25-list_of_catastrophes/ https://florianjehn.github.io/Societal_Collapse/2025-04-25-list_of_catastrophes/ How some societies manage to avoid crisis - When we talk about societal collapse, we usually talk about the factors that led to the collapse of a given civilization. However, you could also turn this around and ask what factors allow civilizations to avoid societal collapse and major crises. Knowing more about this would be quite valuable, because... Wed, 23 Apr 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-04-23-crisis_averted/ https://florianjehn.github.io/Societal_Collapse/2025-04-23-crisis_averted/ Finding papers, coming up with ideas, writing and publishing - So, how do you actually write a living literature review? In the more than two years that I have been writing this (time really flies), sometimes I get asked how I go about writing the posts here. With this post, I want to answer this question. While this is focussed... Tue, 22 Apr 2025 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2025-04-22-write_review/ https://florianjehn.github.io/Societal_Collapse/2025-04-22-write_review/ Hannah Arendt's vision for true freedom - What do you think about when you hear the term revolution? Likely, you think of the French Revolution and things like the Storm of the Bastille, the Guillotine or Louis XVI’s execution. It is on the forefront of our minds, because the French Revolution escalated so quickly and so violently... Thu, 06 Feb 2025 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2025-02-06-revolution/ https://florianjehn.github.io/Societal_Collapse/2025-02-06-revolution/ A primer - Imagine a row of dominoes where knocking over one piece triggers a cascade that topples them all. This is systemic risk - when a single failure can bring down an entire system. Now imagine several such cascade failures happening simultaneously at a global scale and making each other worse. This... Wed, 05 Feb 2025 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2025-02-05-sys_crisis/ https://florianjehn.github.io/Societal_Collapse/2025-02-05-sys_crisis/ If you want to have a stable society, make sure no one is left behind - While writing this living literature review on societal collapse, one topic that keeps popping up again and again is economic inequality. It seems that this inequality makes societies inherently less stable and less able to internally coordinate and thus more vulnerable to collapse. Some examples of us exploring how inequality... Fri, 20 Dec 2024 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2024-12-20-inequality/ https://florianjehn.github.io/Societal_Collapse/2024-12-20-inequality/ How to feed everyone, even in the worst of times - What would we eat if the sun disappeared tomorrow? Or if our electrical grid collapsed worldwide? This is a topic I am quite interested in, because many of the facets of societal collapse are quite intimately linked to the food system. In previous posts we have explored what happens during... Wed, 18 Dec 2024 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2024-12-18-resilient_foods/ https://florianjehn.github.io/Societal_Collapse/2024-12-18-resilient_foods/ Why think about what could have been or might become? - Reflecting about the end of our modern civilization requires counterfactual thinking, because fortunately it hasn’t happened yet. But this is not the only way counterfactuals help us understand collapse better. We can also create counterfactuals to reflect about past events. Not asking “Why did this happen?”, but “Why did not... Tue, 19 Nov 2024 00:00:00 +0100 https://florianjehn.github.io/Societal_Collapse/2024-11-19-counterfactuals/ https://florianjehn.github.io/Societal_Collapse/2024-11-19-counterfactuals/ What happens to a society when the lights go out? - Electricity is essential for the functioning of our modern society, as nearly everything we do depends on the electrical grid in some way. While this reliance provides significant comfort and convenience, it also makes us vulnerable if the grid fails. But what happens when the grid stops working? This question... Sun, 29 Sep 2024 00:00:00 +0200 https://florianjehn.github.io/Societal_Collapse/2024-09-29-blackout/ https://florianjehn.github.io/Societal_Collapse/2024-09-29-blackout/