Metamath Proof Explorer


Theorem sylan2i

Description: A syllogism inference. (Contributed by NM, 1-Aug-1994)

Ref Expression
Hypotheses sylan2i.1 ( 𝜑𝜃 )
sylan2i.2 ( 𝜓 → ( ( 𝜒𝜃 ) → 𝜏 ) )
Assertion sylan2i ( 𝜓 → ( ( 𝜒𝜑 ) → 𝜏 ) )

Proof

Step Hyp Ref Expression
1 sylan2i.1 ( 𝜑𝜃 )
2 sylan2i.2 ( 𝜓 → ( ( 𝜒𝜃 ) → 𝜏 ) )
3 1 a1i ( 𝜓 → ( 𝜑𝜃 ) )
4 3 2 sylan2d ( 𝜓 → ( ( 𝜒𝜑 ) → 𝜏 ) )