Users' Mathboxes Mathbox for Andrew Salmon < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  MPE Home  >  Th. List  >   Mathboxes  >  axc5c4c711toc7 Structured version   Visualization version   GIF version

Theorem axc5c4c711toc7 45155
Description: Rederivation of axc7 2353 from axc5c4c711 45152. Note that neither axc7 2353 nor ax-11 2195 are required for the rederivation. (Contributed by Andrew Salmon, 14-Jul-2011.) (Proof modification is discouraged.) (New usage is discouraged.)
Assertion
Ref Expression
axc5c4c711toc7 (¬ ∀𝑥 ¬ ∀𝑥𝜑𝜑)

Proof of Theorem axc5c4c711toc7
StepHypRef Expression
1 ax-1 6 . . . . . . . 8 (𝜑 → (∀𝑥(𝜑𝜑) → 𝜑))
21alimi 1844 . . . . . . 7 (∀𝑥𝜑 → ∀𝑥(∀𝑥(𝜑𝜑) → 𝜑))
32axc4i 2358 . . . . . 6 (∀𝑥𝜑 → ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑))
43con3i 155 . . . . 5 (¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → ¬ ∀𝑥𝜑)
54alimi 1844 . . . 4 (∀𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → ∀𝑥 ¬ ∀𝑥𝜑)
65sps 2224 . . 3 (∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → ∀𝑥 ¬ ∀𝑥𝜑)
76con3i 155 . 2 (¬ ∀𝑥 ¬ ∀𝑥𝜑 → ¬ ∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑))
8 pm2.21 124 . . . 4 (¬ ∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → (∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → ((𝜑𝜑) → ∀𝑥(∀𝑥(𝜑𝜑) → 𝜑))))
9 axc5c4c711 45152 . . . 4 ((∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → ((𝜑𝜑) → ∀𝑥(∀𝑥(𝜑𝜑) → 𝜑))) → (∀𝑥(𝜑𝜑) → ∀𝑥𝜑))
108, 9syl 18 . . 3 (¬ ∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → (∀𝑥(𝜑𝜑) → ∀𝑥𝜑))
11 sp 2222 . . 3 (∀𝑥𝜑𝜑)
1210, 11syl6 36 . 2 (¬ ∀𝑥𝑥 ¬ ∀𝑥𝑥(∀𝑥(𝜑𝜑) → 𝜑) → (∀𝑥(𝜑𝜑) → 𝜑))
13 pm2.27 43 . . 3 (∀𝑥(𝜑𝜑) → ((∀𝑥(𝜑𝜑) → 𝜑) → 𝜑))
14 id 23 . . 3 (𝜑𝜑)
1513, 14mpg 1830 . 2 ((∀𝑥(𝜑𝜑) → 𝜑) → 𝜑)
167, 12, 153syl 19 1 (¬ ∀𝑥 ¬ ∀𝑥𝜑𝜑)
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  ¬ wn 3  wi 4  wal 1568
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-10 2179  ax-11 2195  ax-12 2216
This proof depends on definitions:  df-bi 210  df-or 862  df-ex 1813  df-nf 1817
This theorem is used by:  axc5c4c711to11  45156
  Copyright terms: Public domain W3C validator