Metamath Proof Explorer


Theorem sylan2d

Description: A syllogism deduction. (Contributed by NM, 15-Dec-2004)

Ref Expression
Hypotheses sylan2d.1 ( 𝜑 → ( 𝜓𝜒 ) )
sylan2d.2 ( 𝜑 → ( ( 𝜃𝜒 ) → 𝜏 ) )
Assertion sylan2d ( 𝜑 → ( ( 𝜃𝜓 ) → 𝜏 ) )

Proof

Step Hyp Ref Expression
1 sylan2d.1 ( 𝜑 → ( 𝜓𝜒 ) )
2 sylan2d.2 ( 𝜑 → ( ( 𝜃𝜒 ) → 𝜏 ) )
3 2 ancomsd ( 𝜑 → ( ( 𝜒𝜃 ) → 𝜏 ) )
4 1 3 syland ( 𝜑 → ( ( 𝜓𝜃 ) → 𝜏 ) )
5 4 ancomsd ( 𝜑 → ( ( 𝜃𝜓 ) → 𝜏 ) )