No. 342 · Fixing problems · Chemistry
Chain Reaction
In a tightly linked system, one small trigger can set off everything after it.
In the Almanac
“Sarajevo”, 1914 · “Silicon Valley Bank”, 2023
Both stories in full, three ways to use it and where it misleads.
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What is Chain Reaction?
A chain reaction is a self-sustaining process where each step triggers the next. One assassination in 1914 dragged Europe into war through alliances, and one announcement in 2023 sparked a bank run that toppled Silicon Valley Bank in two days.
How do you use Chain Reaction?
The links matter more than the spark. Find single points of failure at work, automate payments to stop financial knock-on effects, and pick small habits that trigger healthy ones. You cannot predict every trigger, so build firebreaks where harm could spread.
When does Chain Reaction matter?
Chain Reaction is one of the 40 mental models for fixing problems, the situations where you ask: Why does this keep going wrong, and how do I fix it for good? Within that, it belongs to “How problems spread”, alongside Broken Windows Theory, Containment and Critical Mass.
What is an example of Chain Reaction?
Two stories show it at work: Sarajevo (1914) and Silicon Valley Bank (2023). Both are told in full in The Mental Models Daily Almanac, which has two stories for each of its 365 models.
Which mental models are related to Chain Reaction?
Domino Effect, Critical Mass and Feedback Loops. Chain Reaction itself comes from chemistry.