Users' Mathboxes Mathbox for Richard Penner < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  frege14 Structured version   Visualization version   GIF version

Theorem frege14 44626
Description: Closed form of a deduction based on com3r 88. Proposition 14 of [Frege1879] p. 37. (Contributed by RP, 24-Dec-2019.) (Proof modification is discouraged.)
Assertion
Ref Expression
frege14 ((𝜑 → (𝜓 → (𝜒 → (𝜃𝜏)))) → (𝜑 → (𝜃 → (𝜓 → (𝜒𝜏)))))

Proof of Theorem frege14
StepHypRef Expression
1 frege13 44625 . 2 ((𝜓 → (𝜒 → (𝜃𝜏))) → (𝜃 → (𝜓 → (𝜒𝜏))))
2 frege5 44603 . 2 (((𝜓 → (𝜒 → (𝜃𝜏))) → (𝜃 → (𝜓 → (𝜒𝜏)))) → ((𝜑 → (𝜓 → (𝜒 → (𝜃𝜏)))) → (𝜑 → (𝜃 → (𝜓 → (𝜒𝜏))))))
31, 2ax-mp 5 1 ((𝜑 → (𝜓 → (𝜒 → (𝜃𝜏)))) → (𝜑 → (𝜃 → (𝜓 → (𝜒𝜏)))))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  wi 4
This proof depends on axioms:  ax-mp 5  ax-frege1 44593  ax-frege2 44594  ax-frege8 44612
This theorem is used by:  frege15  44629
  Copyright terms: Public domain W3C validator