No. 288 · Evidence · Physics
Heisenberg Uncertainty Principle
Some things cannot be pinned down at once, and looking closely can change what you see.
In the Almanac
“Heisenberg’s microscope”, 1927 · “College rankings”, 2022
Both stories in full, three ways to use it and where it misleads.
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What is Heisenberg Uncertainty Principle?
The Heisenberg Uncertainty Principle says we cannot know certain pairs of a particle's properties, like position and momentum, with perfect precision at the same time. As a mental model, it reminds us that observation is rarely neutral: rankings, targets and constant check-ins can change the very behavior they measure.
How do you use Heisenberg Uncertainty Principle?
To use it, design metrics with side effects in mind and pair targets with quality checks. Measure yourself at a sensible rhythm rather than obsessively. In relationships, give people space instead of interrogating them. Measure thoughtfully, and hold conclusions with humility.
When does Heisenberg Uncertainty Principle matter?
Heisenberg Uncertainty Principle is one of the 68 mental models for evidence, the situations where you ask: Is this really true? Within that, it belongs to “Where information comes from”, alongside Bias from Incentives, Echo Chambers and Filter Bubble.
What is an example of Heisenberg Uncertainty Principle?
Two stories show it at work: Heisenberg’s microscope (1927) and College rankings (2022). 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 Heisenberg Uncertainty Principle?
Observer Effect, Goodhart’s Law and Proxy. Heisenberg Uncertainty Principle itself comes from physics.