Using two wrestling terms he learned, Mr. Thiel says that many people assumed Mr. Trump was “kayfabe” — a move that looks real but is fake. But then his campaign turned into a “shoot” — the word for an unscripted move that suddenly becomes real.

“People thought the whole Trump thing was fake, that it wasn’t going to go anywhere, that it was the most ridiculous thing imaginable, and then somehow he won, like Hogan did,” Mr. Thiel says. “And what I wonder is, whether maybe pro wrestling is one of the most real things we have in our society and what’s really disturbing is that the other stuff is much more fake. And whatever the superficialities of Mr. Trump might be, he was more authentic than the other politicians. He sort of talked in a way like ordinary people talk. It was not sort of this Orwellian newspeak jargon that so many of the candidates use. So he was sort of real. He actually wanted to win.”

I ask Mr. Thiel about a prescient theory he proffered when I had dinner with him at the convention — again, flipping conventional wisdom — that Hillary was making a mistake by being too optimistic.

“If you’re too optimistic, it sounds like you’re out of touch,” he says. “The Republicans needed a far more pessimistic candidate. Somehow, what was unusual about Trump is, he was very pessimistic but it still had an energizing aspect to it.”

He says he has no plans to buy a place in Washington. “One of the things that’s striking about talking to people who are politically working in D.C. is, it’s so hard to tell what any of them actually do,” he says. “It’s a sort of place where people measure input, not output. You have a 15-minute monologue describing a 15-page résumé, starting in seventh grade.”

While many predict that Mr. Trump will crash and burn, Mr. Thiel does not think he will regret his role.