Let $X / {\sim}$ be a D180: Quotient set.
The canonical set epimorphismto $X / {\sim}$ is the D18: Map
\begin{equation}
X \to X / {\sim}, \quad
x \mapsto {\sim}(x)
\end{equation}
Let $X / {\sim}$ be a D180: Quotient set.
The canonical set epimorphismto $X / {\sim}$ is the D18: Map
\begin{equation}
X \to X / {\sim}, \quad
x \mapsto \{ y : (x, y) \in {\sim} \}
\end{equation}
