Russell's paradox

American  

noun

Mathematics.

1. a paradox of set theory in which an object is defined in terms of a class of objects that contains the object being defined, resulting in a logical contradiction.

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Russell's paradox British  

noun

1. logic the paradox discovered by Bertrand Russell in the work of Gottlob Frege, that the class of all classes that are not members of themselves is a member of itself only if it is not, and is not only if it is. This undermines the notion of an all-inclusive universal class

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Etymology

Origin of Russell's paradox

First recorded in 1920–25; first proposed by Bertrand Russell

Example Sentences

However, the hole in logic, called Russell’s paradox, remained open.

From Forbes

Even if you could, you’d still be stuck with Russell’s paradox.

From Scientific American