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Theorem bj-con2com 34737
Description: A commuted form of the contrapositive, true in minimal calculus. (Contributed by BJ, 19-Mar-2020.)
Assertion
Ref Expression
bj-con2com (𝜑 → ((𝜓 → ¬ 𝜑) → ¬ 𝜓))

Proof of Theorem bj-con2com
StepHypRef Expression
1 con2 135 . 2 ((𝜓 → ¬ 𝜑) → (𝜑 → ¬ 𝜓))
21com12 32 1 (𝜑 → ((𝜓 → ¬ 𝜑) → ¬ 𝜓))
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  34738
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