Theorem exlimivv

Description: Inference form of Theorem 19.23 of Margaris p. 90, see 19.23 . (Contributed by NM, 1-Aug-1995)

	Ref	Expression
Hypothesis	exlimivv.1	⊢ ( 𝜑 → 𝜓 )
Assertion	exlimivv	⊢ ( ∃ 𝑥 ∃ 𝑦 𝜑 → 𝜓 )

Proof

Step	Hyp	Ref	Expression
1		exlimivv.1	⊢ ( 𝜑 → 𝜓 )
2	1	exlimiv	⊢ ( ∃ 𝑦 𝜑 → 𝜓 )
3	2	exlimiv	⊢ ( ∃ 𝑥 ∃ 𝑦 𝜑 → 𝜓 )