Cantor's theorem

Cantor's theorem is a fundamental result in set theory proposed by the mathematician Georg Cantor. It states that for any set \( S \), the set of all subsets of \( S \), known as the power set of \( S \) (denoted as \( \mathcal{P}(S) \)), has a strictly greater cardinality (size) than the set \( S \) itself.