3 ms·
> A => B does not mean !B => !A. Uh... yes, it does. See https://en.wikipedia.org/wiki/Contraposition https://en.wikipedia.org/wiki/Contraposition
by bzbarsky 10y ago
> A => B does not mean !B => !A.
Uh... yes, it does. See https://en.wikipedia.org/wiki/Contraposition https://en.wikipedia.org/wiki/Contraposition