With Trump, there's an ongoing question of whether his worldview is mendacity or insanity. Even on his first day as president, he claimed to have had the biggest inauguration crowd ever, which is a claim only an insane person could have believed, so we just assumed he was lying.... the same way he'd habitually lied about pretty much every business venture in his life, to try to snow the rubes. But there was also the possibility that he'd simply lost touch with reality -- that he wanted to be popular so much that he truly believed he was, and that he'd had a record inauguration crowd, all evidence to the contrary notwithstanding.
Maybe with lifelong con men, the world isn't so binary -- that it's not a question of whether they believe the patently untrue or whether they're lying. Maybe it's all an amorphous thing, where they have spent so long putting no value at all on reality that they don't even stop to think about whether something is true, but just reflexively insist upon whatever assertion would be helpful to them, with the truth or falsehood of the matter never even entering into their mind, as a question too inconsequential to waste mental energy on.
