Metamath Proof Explorer


Theorem 19.37imv

Description: One direction of 19.37v that can be proven without ax-6 . (Contributed by Rohan Ridenour, 16-Apr-2022)

Ref Expression
Assertion 19.37imv ( ∃ 𝑥 ( 𝜑𝜓 ) → ( 𝜑 → ∃ 𝑥 𝜓 ) )

Proof

Step Hyp Ref Expression
1 ax-5 ( 𝜑 → ∀ 𝑥 𝜑 )
2 19.35 ( ∃ 𝑥 ( 𝜑𝜓 ) ↔ ( ∀ 𝑥 𝜑 → ∃ 𝑥 𝜓 ) )
3 2 biimpi ( ∃ 𝑥 ( 𝜑𝜓 ) → ( ∀ 𝑥 𝜑 → ∃ 𝑥 𝜓 ) )
4 1 3 syl5 ( ∃ 𝑥 ( 𝜑𝜓 ) → ( 𝜑 → ∃ 𝑥 𝜓 ) )