2 ms·
> If A -> B is Not logically equivalent as If Not A -> Not B. Many make this mistake. But many people making a mistake won't show that everything anyone says
by thaumasiotes 1y ago
> If A -> B is Not logically equivalent as If Not A -> Not B. Many make this mistake.
But many people making a mistake won't show that everything anyone says is an example of that mistake. Your observation isn't relevant here, because a claim of that form hasn't been made. We don't have "not", we have "less", which behaves differently.
For the claim "f(a) > f(b) -> g(a) > g(b)", it is trivial to show that "f(a) < f(b) -> g(a) < g(b)". These two claims are identical to each other. The proof is one step long.
In the present context, we have f(x) representing "quality of the writing in x" and g(x) representing "likelihood that the ideas in x are correct".