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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.


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

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Etymology

Origin of reductio ad absurdum

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

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

Maybe all this can be read as an ironic coda to the last 80 years of U.S. global domination, the reductio ad absurdum of American exceptionalism.

From Salon

Because IVF is popular with voters, donors and even legislators, so defending Alabama’s reductio ad absurdum decision would be political suicide.

From Seattle Times

He seems to have viewed superdeterminism as a reductio ad absurdum proposition, which highlights the strangeness of quantum mechanics.

From Scientific American

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

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