Theorem elexi

Description: If a class is a member of another class, then it is a set. Inference associated with elex . (Contributed by NM, 11-Jun-1994)

	Ref	Expression
Hypothesis	elexi.1	$$⊢A\in B$$
Assertion	elexi	$$⊢A\in \mathrm{V}$$

Proof

Step	Hyp	Ref	Expression
1		elexi.1	$$⊢A\in B$$
2		elex	$$⊢A\in B\to A\in \mathrm{V}$$
3	1 2	ax-mp	$$⊢A\in \mathrm{V}$$