Metamath Proof Explorer


Theorem bj-con2com

Description: A commuted form of the contrapositive, true in minimal calculus. (Contributed by BJ, 19-Mar-2020)

Ref Expression
Assertion bj-con2com φ ψ ¬ φ ¬ ψ

Proof

Step Hyp Ref Expression
1 con2 ψ ¬ φ φ ¬ ψ
2 1 com12 φ ψ ¬ φ ¬ ψ