User:Dfeuer/Definition:Empty Class

Definition
The empty class, denoted $\varnothing$, is the class with the property that:


 * $\forall x: \lnot (x \in \varnothing)$

Also known as
In light of the User:Dfeuer/Axiom of the Empty Set, the empty class is also called the empty set or the null set.

Also see

 * User:Dfeuer/Empty Class Exists and is Unique