Metamath Proof Explorer


Theorem expd

Description: Exportation deduction. (Contributed by NM, 20-Aug-1993) (Proof shortened by Wolf Lammen, 28-Jul-2022)

Ref Expression
Hypothesis expd.1 ( 𝜑 → ( ( 𝜓𝜒 ) → 𝜃 ) )
Assertion expd ( 𝜑 → ( 𝜓 → ( 𝜒𝜃 ) ) )

Proof

Step Hyp Ref Expression
1 expd.1 ( 𝜑 → ( ( 𝜓𝜒 ) → 𝜃 ) )
2 1 expdcom ( 𝜓 → ( 𝜒 → ( 𝜑𝜃 ) ) )
3 2 com3r ( 𝜑 → ( 𝜓 → ( 𝜒𝜃 ) ) )