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Theorem hbn1 708
Description: x is not free in ¬ ∀xφ.
Assertion
Ref Expression
hbn1 (¬ ∀xφ → ∀x ¬ ∀xφ)

Proof of Theorem hbn1
StepHypRef Expression
1 hba1 698 . 2 (∀xφ → ∀xxφ)
21hbne 699 1 (¬ ∀xφ → ∀x ¬ ∀xφ)
Colors of variables: wff set class
Syntax hints:  ¬ wn 1   → wi 2  ∀wal 672
This theorem is referenced by:  hbe1 709  ax6 711  eqs1 828  eqs2 829  ax15 1006
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-gen 677
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