In a rare expression of self-awareness, President Trump admitted — nay, boasted — that he just makes stuff up.

Recounting a recent meeting with Canadian Prime Minister Justin Trudeau, Trump says Trudeau told him that the U.S. has no trade deficit with Canada, whereupon Trump essentially said, Yes, we do, whereupon Trudeau said, No you don’t.

Here’s the hitch: Trump didn’t really know whether his claim was true. He was flying by the seat of his pants, bluffing, playing the wise guy on a wacky little whim all his own. He bragged as much in a speech during a private, fundraising event in Missouri last week.

Such a character, that guy.

But what was Trump thinking during the alleged meeting? Was he pulling Trudeau’s leg? Was he curious to see how it would feel to toss out a whopper and see how it landed?

“Trudeau came to see me. He’s a good guy, Justin,” Trump told his audience. “He [Trudeau] said, ‘No, no, we have no trade deficit with you, we have none. Donald, please.'” Trump apparently mimicked Trudeau’s voice, according to audio obtained by The Washington Post. “Nice guy, good-looking guy, comes in — ‘Donald, we have no trade deficit.’ He’s very proud because everybody else, you know, we’re getting killed. …

“So, he’s proud. I said, ‘Wrong, Justin, you do.’ I didn’t even know. … I had no idea. I just said, ‘You’re wrong.’ You know why? Because we’re so stupid. … And I thought they were smart. I said, ‘You’re wrong, Justin.’ He said, ‘Nope, we have no trade deficit.’ I said, ‘Well, in that case, I feel differently,’ I said, ‘but I don’t believe it.’ I sent one of our guys out, his guy, my guy, they went out, I said, ‘Check, because I can’t believe it.'”

Believe it.

The truth is the U.S. had a trade surplus with Canada to the tune of $2.8 billion in goods and services in 2017, according to the U.S. Commerce Department. But facts seem neither an attractant nor a deterrent to Trump, who at times reminds me of Don Quixote, the fictional knight-errant of 17th-century Spanish writer Miguel de Cervantes. Quixote had read a few too many books of chivalry and, owing to some deterioration of his mental faculties, fancied himself a knight in shining armor.

Like the president, he would make up stuff or imagine, for example, that ordinary windmills were giants to be slayed. Hence the expression “tilting at windmills.”

Imagining enemies where none exist — or failing to recognize a proper foe and treat him accordingly — is an entertaining fictional device. But such deliriums are far less amusing in a world leader whose vision of his own grandeur often cloud both his judgment and perceptions.

But, that’s not all, folks. Not only did Trump invent the trade deficit, he also may have made up the meeting itself. According to Canada’s National Post, Trudeaus’ government isn’t sure which meeting Trump was referencing. There may have been a telephone conversation or two along those lines, or, quite possibly, Trump created a composite scenario drawn from both meetings and conversations.

This brings us to a new black hole in the fact-checking universe. Not only do weary researchers have to check Trump’s “facts,” but now they also have to check his facts about fictions. If the meeting didn’t actually take place — and the claim about the trade deficit was fantastic in the correct sense — then what is one ever to believe from this president?

And what sorts of ruminations might Trump be conjuring in anticipation of his proposed meeting with North Korea’s Kim Jong Un’s entertainment? Perhaps Trump will tease that he’s pulling back American troops along the Demilitarized Zone in exchange for his hair stylist’s contact info. (That would be amusing, come to think of it.)

One might be inclined to dismiss Trump’s relatively harmless tale as poetic license in the tradition of story-telling. It’s doubtful that anyone at the fundraiser cared whether the meeting was real or some variation thereof. What’s concerning is: (1) the president’s admission that he made stuff up; (2) didn’t bother to bone up on our trade relationship with Canada before challenging Trudeau; and (3) seemingly doesn’t give a damn.

In mathematics, as I vaguely recall, a double negative makes a positive. In other words, two minuses are a plus. Maybe Trump figures he’s entitled to the same sort of calculation. In the fantasy-filled mind of a fiction-prone president, willfully making a false claim in a meeting that didn’t happen comes out to a plus. Then he can boast a great, big, beautiful double-whammy.

Believe it. Or, not.