ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  nfnth GIF version

Theorem nfnth 1354
Description: No variable is (effectively) free in a non-theorem. (Contributed by Mario Carneiro, 6-Dec-2016.)
Hypothesis
Ref Expression
nfnth.1 ¬ 𝜑
Assertion
Ref Expression
nfnth 𝑥𝜑

Proof of Theorem nfnth
StepHypRef Expression
1 nfnth.1 . . 3 ¬ 𝜑
21pm2.21i 575 . 2 (𝜑 → ∀𝑥𝜑)
32nfi 1351 1 𝑥𝜑
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wal 1241  wnf 1349
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101  ax-in2 545  ax-gen 1338
This theorem depends on definitions:  df-bi 110  df-nf 1350
This theorem is referenced by: (None)
  Copyright terms: Public domain W3C validator