Theorem bnj937

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

	Ref	Expression
Hypothesis	bnj937.1	⊢ ( 𝜑 → ∃ 𝑥 𝜓 )
Assertion	bnj937	⊢ ( 𝜑 → 𝜓 )

Proof

Step	Hyp	Ref	Expression
1		bnj937.1	⊢ ( 𝜑 → ∃ 𝑥 𝜓 )
2		19.9v	⊢ ( ∃ 𝑥 𝜓 ↔ 𝜓 )
3	1 2	sylib	⊢ ( 𝜑 → 𝜓 )