Users' Mathboxes Mathbox for Scott Fenton < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  hbntg Structured version   Visualization version   GIF version

Theorem hbntg 33687
Description: A more general form of hbnt 2294. (Contributed by Scott Fenton, 13-Dec-2010.)
Assertion
Ref Expression
hbntg (∀𝑥(𝜑 → ∀𝑥𝜓) → (¬ 𝜓 → ∀𝑥 ¬ 𝜑))

Proof of Theorem hbntg
StepHypRef Expression
1 axc7 2315 . . 3 (¬ ∀𝑥 ¬ ∀𝑥𝜓𝜓)
21con1i 147 . 2 𝜓 → ∀𝑥 ¬ ∀𝑥𝜓)
3 con3 153 . . 3 ((𝜑 → ∀𝑥𝜓) → (¬ ∀𝑥𝜓 → ¬ 𝜑))
43al2imi 1819 . 2 (∀𝑥(𝜑 → ∀𝑥𝜓) → (∀𝑥 ¬ ∀𝑥𝜓 → ∀𝑥 ¬ 𝜑))
52, 4syl5 34 1 (∀𝑥(𝜑 → ∀𝑥𝜓) → (¬ 𝜓 → ∀𝑥 ¬ 𝜑))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4  wal 1537
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1799  ax-4 1813  ax-5 1914  ax-6 1972  ax-7 2012  ax-10 2139  ax-12 2173
This theorem depends on definitions:  df-bi 206  df-ex 1784
This theorem is referenced by:  hbimtg  33688  hbng  33690
  Copyright terms: Public domain W3C validator