The relationship between logical implication and the subset relation
From Maths
Definition
[math]A\subset B[/math] (and we say "A is a subset of B") if and only if every element of [math]A[/math] also belongs to [math]B[/math]
That is: [math][A\subset B]\iff[x\in A\implies x\in B][/math][1]
References
- ↑ Definition 3.10 (p10) - Introduction to Set Theory, Third Edition (Revised and Expanded) - Karel Hrbacek and Thomas Jech
