Russell's Paradox/Corollary

Corollary to Russell's Paradox

 * $\not \exists x: \forall y: \paren {\map \RR {x, y} \iff \neg \map \RR {y, y} }$

Given a relation $\RR$, there cannot exist an element $x$ that bears $\RR$ to all $y$ that do not bear $\RR$ to $y$.