All evidence suggests only thing Trump believes in is the promotion of himself. His political, business, personal and whatever else philosophy is the same: Trumpism. It’s the only common mooring for everything he says and does. Trumpism is at the root of Trump’s total lack of shame, which as Ezra Klein has pointed out is probably his biggest advantage over the other candidates:

Most people feel shame when they’re exposed as liars, when they’re seen as uninformed, when their behavior is thought cruel, when respected figures in their party condemn their actions, when experts dismiss their proposals, when they are mocked and booed and protested.

Trump doesn’t. He has the reality television star’s ability to operate entirely without shame, and that permits him to operate entirely without restraint. It is the single scariest facet of his personality. It is the one that allows him to go where others won’t, to say what others can’t, to do what others wouldn’t.

Basically, he can lie his ass off to such a spectacular level that it works, because we aren’t conditioned that someone, especially a presidential candidate, can lie to that degree. I realize of course politicians are famously characterized as liars, but usually there is at least some tenuous tether to something that is or at least once was true. But Trump is utterly unconcerned with that. Whatever words serve Trumpism will do.