No. 332 · Fixing problems · Equations
Proximate vs Root Cause
The trigger that sets off a problem is rarely the condition that made it possible.
In the Almanac
“The Tay Bridge”, 1879 · “Boeing 737 MAX”, 2018–2019
Both stories in full, three ways to use it and where it misleads.
Get the AlmanacQuestions
What is Proximate vs Root Cause?
Every failure has a trigger and a foundation. The proximate cause is what happened just before things broke. The root cause is the underlying flaw that made the break possible, and it will keep producing new problems until it's fixed.
How do you use Proximate vs Root Cause?
When something goes wrong, keep asking why until you reach a cause you can change. Patch the symptom if you must, but then fix the system that produced it.
When does Proximate vs Root Cause matter?
Proximate vs Root Cause 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 “Finding the real cause”, alongside Black Box, First Principles Thinking and Inversion.
What is an example of Proximate vs Root Cause?
Two stories show it at work: The Tay Bridge (1879) and Boeing 737 MAX (2018–2019). 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 Proximate vs Root Cause?
Causal Fallacy, Margin of Safety and Second-Order Thinking. Proximate vs Root Cause itself comes from equations.