Reflexive Relation

A binary relation $R$ over a set $X$ is reflexive if it relates every $x \in X$ to itself.

$$\begin{equation} \forall x \in X \,|\, xRx \end{equation}$$

An example of a reflexive relation is “is equal to” since any number within $\mathbb{R}$ would be mapped back to itself.

Tao’s definition:

Given any object x, we have $x = x$.

See also:

• Symmetric Relation

• Transitive Relation