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Metamath Proof Explorer

Theorem orrd

Description: Deduce disjunction from implication. (Contributed by NM, 27-Nov-1995)

		Ref	Expression
	Hypothesis	orrd.1	$⊢ φ \to (\neg ψ \to χ)$
	Assertion	orrd	$⊢ φ \to (ψ \lor χ)$

Step	Hyp	Ref	Expression
1		orrd.1	$⊢ φ \to (\neg ψ \to χ)$
2		pm2.54	$⊢ (\neg ψ \to χ) \to (ψ \lor χ)$
3	1 2	syl	$⊢ φ \to (ψ \lor χ)$