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Theorem bj-con2com 30919
Description: A commuted form of the contrapositive, true in minimal calculus. (Contributed by BJ, 19-Mar-2020.)
Assertion
Ref Expression
bj-con2com  |-  ( ph  ->  ( ( ps  ->  -. 
ph )  ->  -.  ps ) )

Proof of Theorem bj-con2com
StepHypRef Expression
1 con2 119 . 2  |-  ( ( ps  ->  -.  ph )  ->  ( ph  ->  -.  ps ) )
21com12 32 1  |-  ( ph  ->  ( ( ps  ->  -. 
ph )  ->  -.  ps ) )
Colors of variables: wff setvar class
Syntax hints:   -. wn 3    -> wi 4
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem is referenced by:  bj-con2comi  30920
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