"How Do You Disprove A Fallacy?": How To Win The Rhetorical War Over Trump's Mental Acuity

Yup.
I mean, gosh, where did these questions about Trump's narcissism, derangement, ignorance and general just-not-really-the-very-sharpest-tool-in-the-shed-ness come from anyway? How can such charges just be fabricated entirely out of thin air,without a single bit of evidence to back them up? It's a mystery.
   The real question is: how do you disprove a set of mutually-supporting, repeatedly-confirmed propositions that seem pretty much beyond question to anyone who's paying any attention at all and knows even a little bit about human beings?
   Now that ain't easy.