Theorem orfa1

Description: Add a contradicting disjunct to an antecedent. (Contributed by Giovanni Mascellani, 15-Sep-2017)

	Ref	Expression
Hypothesis	orfa1.1	$$⊢\phi \to \psi$$
Assertion	orfa1	$$⊢\left(\phi \vee \perp \right)\to \psi$$

Proof

Step	Hyp	Ref	Expression
1		orfa1.1	$$⊢\phi \to \psi$$
2		falim	$$⊢\perp \to \psi$$
3	1 2	jaoi	$$⊢\left(\phi \vee \perp \right)\to \psi$$