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Theorem dftru2 1378
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  |-  ( T.  <-> 
( ph  ->  ph )
)

Proof of Theorem dftru2
StepHypRef Expression
1 tru 1374 . 2  |- T.
2 id 22 . 2  |-  ( ph  ->  ph )
31, 22th 239 1  |-  ( T.  <-> 
( ph  ->  ph )
)
Colors of variables: wff setvar class
Syntax hints:    -> wi 4    <-> wb 184   T. wtru 1371
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 185  df-tru 1373
This theorem is referenced by: (None)
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