Quotations

Extraordinary evidence

Published

5 October 2026

“Extraordinary claims require extraordinary evidence.”

Carl SaganCosmos, 1980

Why it stays with me

This is the shortest useful rule I know for thinking about surprising news. The more a claim would overturn what we already know, the stronger the evidence has to be before I accept it.

It is not a rule for dismissing new ideas. Plenty of extraordinary claims turned out to be true, from continental drift to the expansion of the universe. They were accepted because the evidence eventually became extraordinary too.

What I like about it is that it is fair in both directions. It asks me to stay open, and it asks me to wait. Most of the time the honest answer to a big claim is not yes or no, but “not yet”.

Ayoub Khallok keeps this archive of essays, research, lessons and notes, written to understand things more clearly. More about Ayoub.

If something here is wrong or unclear, tell me. Corrections are added with a note and the date of the change.

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