indirect proof

American  

noun

1. an argument for a proposition that shows its negation to be incompatible with a previously accepted or established premise.

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indirect proof British  

noun

1. logic maths proof of a conclusion by showing its negation to be self-contradictory; reductio ad absurdum Compare direct

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Example Sentences

See Examples For:

indirect proof

They have never been seen directly, though an indirect proof of their existence, based on studying a pair of collapsed stars, was rewarded with the 1993 Nobel prize in physics.

From Economist ● Mar. 20, 2014

I was about to begin going over the steps of indirect proof when I heard Danny say, “You’re always sleeping! What a sleepyhead you are!” and I opened my eyes.

From "The Chosen" by Chaim Potok

And we have, as has been pointed out, interesting indirect proof as to what manner of life He lived on those workaday levels that we all know so much about.

From One Day at a Time and Other Talks on Life and Religion by Alexander, Arch.

Since a direct proof is impossible, an attempt was made to construct an indirect proof by a comparison of bodily-organs.

From At the Deathbed of Darwinism A Series of Papers by O'Harra, Edwin V.

This declaration, in itself an indirect proof of guilt, occasioned some commotion in the House.

From Memoirs of Extraordinary Popular Delusions — Volume 1 by Mackay, Charles