1. reductio ad absurdum
Wikipedia definition
2. Reductio ad absurdumFor the mathematical form of proof by contradiction, see Proof by contradiction. Reductio ad absurdum is a form of argument in which a proposition is disproven by following its implications logically to an absurd consequence. A common type of reductio ad absurdum is proof by contradiction (also called indirect proof), where a proposition is proved true by proving that it is impossible for it to be false.
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