Metamath Proof Explorer


Theorem pm2.61d2

Description: Inference eliminating an antecedent. (Contributed by NM, 18-Aug-1993)

Ref Expression
Hypotheses pm2.61d2.1 ( 𝜑 → ( ¬ 𝜓𝜒 ) )
pm2.61d2.2 ( 𝜓𝜒 )
Assertion pm2.61d2 ( 𝜑𝜒 )

Proof

Step Hyp Ref Expression
1 pm2.61d2.1 ( 𝜑 → ( ¬ 𝜓𝜒 ) )
2 pm2.61d2.2 ( 𝜓𝜒 )
3 2 a1i ( 𝜑 → ( 𝜓𝜒 ) )
4 3 1 pm2.61d ( 𝜑𝜒 )