Changes

Its existence is postulated by the [[Axiom of empty set]] in the axioms of [[Zermelo–Fraenkel set theory]]. Though this seems counterintuitive, the empty set is a subset of the empty set, and the empty set is [[disjoint]] with itself.  More generally, the union of any set with the empty set is the original set, while the intersection of any set with the empty set is itself the empty set.

Its existence is postulated by the [[Axiom of empty set]] in the axioms of [[Zermelo–Fraenkel set theory]]. Though this seems counterintuitive, the empty set is a subset of the empty set, and the empty set is [[disjoint]] with itself.  More generally, the union of any set with the empty set is the original set, while the intersection of any set with the empty set is itself the empty set.

[[Category: set theory]]

[[Category:Set Theory]]