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Theorem dftru2 1531
Description: An alternate definition of "true". (Contributed by Anthony Hart, 13-Oct-2010.) (Revised by BJ, 12-Jul-2019.) (New usage is discouraged.)
Assertion
Ref Expression
dftru2 (⊤ ↔ (𝜑𝜑))

Proof of Theorem dftru2
StepHypRef Expression
1 tru 1527 . 2
2 id 22 . 2 (𝜑𝜑)
31, 22th 254 1 (⊤ ↔ (𝜑𝜑))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 196  wtru 1524
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 197  df-tru 1526
This theorem is referenced by: (None)
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