Jump to navigation Jump to search
Let $S$ and $T$ be sets.
$S$ is smaller than $T$ can be denoted:
- $S \le T$
Also defined as
Also denoted as
- $\card S \le \card T$
Also known as
If $S$ is smaller than $T$, then $S$ is said to be of lower cardinality or smaller cardinality than $T$.
- 1996: Winfried Just and Martin Weese: Discovering Modern Set Theory. I: The Basics ... (previous) ... (next): Part $1$: Not Entirely Naive Set Theory: Chapter $3$: Cardinality: Definition $2$
- 2010: Raymond M. Smullyan and Melvin Fitting: Set Theory and the Continuum Problem (revised ed.) ... (previous) ... (next): Chapter $1$: General Background: $\S 4$ Larger and smaller