ThmDex – An index of mathematical definitions, results, and conjectures.

▼	Set of symbols
▼	Alphabet
▼	Deduction system
▼	Theory
▼	Zermelo-Fraenkel set theory
▼	Set
▼	Binary cartesian set product
▼	Binary relation
▼	Empty binary relation

Definition D5066

Canonical empty binary relation

Formulation 0

A D4: Binary relation $(X \times Y, R)$ is a canonical empty binary relation if and only if

(1)	$R = \emptyset$	D857: Empty binary relation
(2)	$X \times Y = \emptyset$