Metamath Proof Explorer


Theorem jctil

Description: Inference conjoining a theorem to left of consequent in an implication. (Contributed by NM, 31-Dec-1993)

Ref Expression
Hypotheses jctil.1 ( 𝜑𝜓 )
jctil.2 𝜒
Assertion jctil ( 𝜑 → ( 𝜒𝜓 ) )

Proof

Step Hyp Ref Expression
1 jctil.1 ( 𝜑𝜓 )
2 jctil.2 𝜒
3 2 a1i ( 𝜑𝜒 )
4 3 1 jca ( 𝜑 → ( 𝜒𝜓 ) )