Metamath Proof Explorer


Theorem syl3an

Description: A triple syllogism inference. (Contributed by NM, 13-May-2004)

Ref Expression
Hypotheses syl3an.1 ( 𝜑𝜓 )
syl3an.2 ( 𝜒𝜃 )
syl3an.3 ( 𝜏𝜂 )
syl3an.4 ( ( 𝜓𝜃𝜂 ) → 𝜁 )
Assertion syl3an ( ( 𝜑𝜒𝜏 ) → 𝜁 )

Proof

Step Hyp Ref Expression
1 syl3an.1 ( 𝜑𝜓 )
2 syl3an.2 ( 𝜒𝜃 )
3 syl3an.3 ( 𝜏𝜂 )
4 syl3an.4 ( ( 𝜓𝜃𝜂 ) → 𝜁 )
5 1 2 3 3anim123i ( ( 𝜑𝜒𝜏 ) → ( 𝜓𝜃𝜂 ) )
6 5 4 syl ( ( 𝜑𝜒𝜏 ) → 𝜁 )