Editing Reflexive relation (section)

{{short description|Binary relation that relates every element to itself}}
{{Binary relations}}
In [[mathematics]], a [[binary relation]] <math>R</math> on a [[Set (mathematics)|set]] <math>X</math> is '''reflexive''' if it relates every element of <math>X</math> to itself.{{sfn|ps=|Levy|1979|p=74}}{{sfn|ps=|Schmidt|2010}} 

An example of a reflexive relation is the relation "[[Equality (mathematics)|is equal to]]" on the set of [[real number]]s, since every real number is equal to itself.  A reflexive relation is said to have the '''reflexive property''' or is said to possess '''reflexivity'''.  Along with [[Symmetric relation|symmetry]] and [[Transitive relation|transitivity]], reflexivity is one of three properties defining [[equivalence relation]]s.