The president is often portrayed as a cynical politician who lies and spreads conspiracy theories to rile up his populist base, but a new report in The New York Times suggests even this interpretation is too generous. According to three sources close to Trump, he has suggested to people this year that the infamous Access Hollywood tape (which he has publicly acknowledged as real) is a forgery and that he wants it investigated. And that’s not all.

“Mr. Trump’s falsehoods about the Access Hollywood tape are part of his lifelong habit of attempting to create and sell his own version of reality,” Maggie Haberman and Jonathan Martin wrote. “Advisers say he continues to privately harbor a handful of conspiracy theories that have no grounding in fact.” For instance, Trump continues “to question the authenticity of President Barack Obama’s birth certificate,” to claim that voter fraud cost him the popular the vote, and that a majority of women voted for him (when in fact only 42 percent did).

That the president of the United States is so delusional is disturbing, but the patterns of his delusions are revealing. Trump’s great talent is as a salesman, and in sales, it’s essential to believe in your product. He’s repeated these lies so often, he’s convinced himself that they’re true. What other of his countless lies might he believe?