── ── Mental model
Thought Experiment
A thought experiment is structured reasoning: construct a scenario, trace logical consequences of explicit premises, examine the result for contradiction, hidden assumptions, or new hypotheses. Not vague speculation — formal procedure with defensible steps.
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How it works
Step 1 — Frame: question being reasoned about · why it can't be tested · type of useful conclusion (refute / surface assumption / generate hypothesis).
Step 2 — Premises: main premise · auxiliary premises (surface unstated ones) · most-controversial premise.
Step 3 — Reason step by step: each step follows from prior premises by a named inference rule; each step defensible in isolation.
When to use it
- user says 'what if,' 'let's reason through this,' 'imagine that,' or 'thought experiment'
- a strategic decision is too risky or irreversible to test empirically
- someone wants to refute a claim by reasoning rather than data
- hidden assumptions in a business model need surfacing
- counterfactual or ethical analysis is requested
When not to use it
the question can be empirically tested at reasonable cost; time pressure makes structured reasoning impractical.
Worked example
Galileo Falling Bodies + Einstein Light Beam + Modern Strategic Applications
Galileo's chained-balls argument (~1638) is the canonical refutation-via-thought-experiment. The argument's structure:
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