Metamath Proof Explorer


Theorem imorri

Description: Infer implication from disjunction. (Contributed by Jonathan Ben-Naim, 3-Jun-2011)

Ref Expression
Hypothesis imorri.1 ¬φψ
Assertion imorri φψ

Proof

Step Hyp Ref Expression
1 imorri.1 ¬φψ
2 imor φψ¬φψ
3 1 2 mpbir φψ