reductio ad absurdum

American  

[ri-duhk-tee-oh ad ab-sur-duhm, -zur-, -shee-oh] / rɪˈdʌk tiˌoʊ ˈæd æbˈsɜr dəm, -ˈzɜr-, -ʃiˌoʊ /

noun

Logic.

1. a reduction to an absurdity; the refutation of a proposition by demonstrating the inevitably absurd conclusion to which it would logically lead.

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reductio ad absurdum British  

/ rɪˈdʌktɪəʊ æd æbˈsɜːdəm /

noun

1. a method of disproving a proposition by showing that its inevitable consequences would be absurd

2. a method of indirectly proving a proposition by assuming its negation to be true and showing that this leads to an absurdity

3. application of a principle or proposed principle to an instance in which it is absurd

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Etymology

Origin of reductio ad absurdum

First recorded in 1735–45, reductio ad absurdum is from Latin reductiō ad absurdum

Example Sentences

But that reductio ad absurdum argument is not enough when millions of people have already accepted the absurdity.

From Slate • Oct. 22, 2021

Ross provides a reductio ad absurdum for a quiet digital-age truth: A sprinkling of coveted intellectual property can allow a shrewd company to punch well above its weight.

From Washington Post • Jul. 30, 2021

It’s the reductio ad absurdum of Neumann’s “capitalist kibbutz”: Everyone is deserving of “growth,” but some are apparently more deserving than others.

From New York Times • Oct. 21, 2020

To some, the arguments over "that damned meteorite" represent diminishing returns, a reductio ad absurdum with no way out of a particularly complicated labyrinth.

From Salon • Jun. 13, 2020

They indulge as well in reductio ad absurdum, the logical practice of taking any premise to an extreme, and in various sorts of combinatorial word play.

From "Innumeracy: Mathematical Illiteracy and Its Consequences" by John Allen Paulos