러셀의 역설

One of the logical paradoxes - a contradiction - in naive set theory, discovered by Bertrand Russell in or around 1901.

Let $R = \{x \mid x \notin x\}$ then $R \in R \iff R \notin R$.

Articles

• plato.stanford.edu/entries/russell-paradox/
• en.wikipedia.org/wiki/Russell%27s_paradox