No. 20 · Decisions · General Thinking
Thought Experiment
Careful imagination can test an idea before it costs you anything.
In the Almanac
“Galileo’s tied stones”, 1638 · “Intel”, 1985
Both stories in full, three ways to use it and where it misleads.
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Questions
What is Thought Experiment?
A Thought Experiment is a mental exercise where you imagine a situation and reason through what would happen. By changing a detail, pushing an idea to its extreme or seeing through someone else's eyes, you can expose contradictions and options that ordinary thinking misses.
How do you use Thought Experiment?
Use it before costly decisions. Ask what a fresh stranger would do in your role, imagine owning a purchase for a year, or picture a fair friend hearing both sides of an argument. Then check your conclusions against real evidence.
When does Thought Experiment matter?
Thought Experiment is one of the 35 mental models for decisions, the situations where you ask: Which way should I go? Within that, it belongs to “Thinking ahead”, alongside Counterfactual Thinking, Exit Strategy and OODA Loop.
What is an example of Thought Experiment?
Two stories show it at work: Galileo’s tied stones (1638) and Intel (1985). 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 Thought Experiment?
First Principles Thinking, Inversion and Sunk Cost Fallacy. Thought Experiment itself comes from general thinking.