Fermi Estimation

Produce an answer that is numerically useful, transparent about uncertainty, and persuasive to a skeptical reader. Favor externally checkable facts over intuition, and turn intuition into labeled assumptions only after exhausting accessible evidence.

Core Workflow

1. Define the target precisely.
2. Gather accessible evidence before inventing assumptions.
3. Decompose the target into a small number of drivers.
4. Assign low/base/high values to each driver.
5. Calculate the estimate and stress-test it.
6. Present the conclusion, uncertainty, and biggest drivers.

If the user says to solve by Fermi estimation, do not stop for approval. Work through to a final answer with the best evidence you can access.

When Not To Use It

Do not use Fermi estimation when a current primary-source answer is directly available with a quick lookup.