Set Complement inverts Subsets/Proof 3

Proof
By definition of set complement:
 * $\map \complement T := \relcomp {\mathbb U} T$

where:
 * $\mathbb U$ is the universe
 * $\relcomp {\mathbb U} T$ denotes the complement of $T$ relative to $\mathbb U$.

Thus the statement can be expressed as:
 * $S \subseteq T \iff \relcomp {\mathbb U} T \subseteq \relcomp {\mathbb U} S$

The result then follows from Relative Complement inverts Subsets.