Extraordinary claims require extraordinary evidence. — Carl Sagan · Smartyfair

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Extraordinary claims require extraordinary evidence. — Carl Sagan · Smartyfair

Extraordinary claims require extraordinary evidence.

Carl Sagan1934–1996 · scientist · 1900s USACarl Sagan was an astronomer who helped millions of people fall in love with the stars.13 quotes

Source foundScience

In plain words

The wilder the claim, the better the proof had better be.

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extraordinary
claims
require
evidence

Where these words come from

How sure this is: 87% sureThese words were traced back to where they first appeared. That source is listed below.
What turned up: Broca's Brain (1979), Chapter 5 "Night Walkers and Mystery Mongers," p. 73
Sources checked: en.wikiquote.orgChecked using claude-sonnet-5, 20 August 2026

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