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Metamath Proof Explorer

Theorem bj-19.23bit

Description: Closed form of 19.23bi . (Contributed by BJ, 20-Oct-2019)

		Ref	Expression
	Assertion	bj-19.23bit	$⊢ (\exists x φ \to ψ) \to (φ \to ψ)$

Step	Hyp	Ref	Expression
1		19.8a	$⊢ φ \to \exists x φ$
2	1	imim1i	$⊢ (\exists x φ \to ψ) \to (φ \to ψ)$