#summary An explanation of Russell's Paradox.
#labels Glossary

= Russell's Paradox =

Russell's pardox, described in 1901 by Bertrand Russell, can be summarized as:

  "Let M be the set of all sets that do not contain themselves as members." 

This set is well-defined according to the classical set-theory, but it contains a mathematical contradiction: M can neither be included nor excluded from this set.

This observation was the impetus for the development of [TypeTheory type theory].  