A set $T$ is transitive if every element of $T$ is a subset of $T$.
The following statements are equivalent:
- $T$ is transitive.
- $\bigcup T\subseteq T$.
- $T\subseteq\powerset(T)$.
A set $T$ is transitive if every element of $T$ is a subset of $T$.
The following statements are equivalent:
- $T$ is transitive.
- $\bigcup T\subseteq T$.
- $T\subseteq\powerset(T)$.