Constant Operation is Commutative

Theorem
Let $S$ be a set.

Let $x \left[{c}\right] y = c$ be a constant operation on $S$.

Then $\left[{c}\right]$ is a commutative operation:


 * $\forall x, y \in S: x \left[{c}\right] y = y \left[{c}\right] x$

Proof
Hence the result by definition of commutativity.