Russell's paradox

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.

Origin of Russell's paradox

First recorded in 1920–25; first proposed by Bertrand Russell
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British Dictionary definitions for russell's paradox

Russell's paradox

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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