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

Theorem nottru 1320
Description: A ¬ identity. (Contributed by Anthony Hart, 22-Oct-2010.)
Assertion
Ref Expression
nottru (¬ ⊤ ↔ ⊥)

Proof of Theorem nottru
StepHypRef Expression
1 df-fal 1265 . 2 (⊥ ↔ ¬ ⊤)
21bicomi 127 1 (¬ ⊤ ↔ ⊥)
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wb 102  wtru 1260  wfal 1264
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 103  ax-ia2 104  ax-ia3 105
This theorem depends on definitions:  df-bi 114  df-fal 1265
This theorem is referenced by:  truxortru  1326
  Copyright terms: Public domain W3C validator