Theorem ne0ii

Description: If a class has elements, then it is nonempty. Inference associated with ne0i . (Contributed by Glauco Siliprandi, 11-Dec-2019)

	Ref	Expression
Hypothesis	n0ii.1	⊢ 𝐴 ∈ 𝐵
Assertion	ne0ii	⊢ 𝐵 ≠ ∅

Proof

Step	Hyp	Ref	Expression
1		n0ii.1	⊢ 𝐴 ∈ 𝐵
2		ne0i	⊢ ( 𝐴 ∈ 𝐵 → 𝐵 ≠ ∅ )
3	1 2	ax-mp	⊢ 𝐵 ≠ ∅