Michael Moore has a theory about Donald Trump: The Republican nominee never wanted to be president, and he is now sabotaging his campaign as a way to get out of the race. “Donald Trump never actually wanted to be president of the United States. I know this for a fact,” the well-known documentary filmmaker wrote on his website earlier this week. Moore does not offer concrete evidence for his claim. “I’m not going to say how I know it,” he wrote. If you want to believe what he has to say, you have to trust him.

The claims have been shared thousands of times on social media and re-printed in media outlets, including The Huffington Post and CNBC.  It’s the latest in a series of high-profile statements Moore has made about Trump.  He recently penned an open letter to Ivanka Trump imploring her to stage an intervention as her father’s “comments and behavior have become more and more bizarre and detached from reality.” In May, Moore told Bill Maher “you and I are going to take him down” on an episode of HBO’s Real Time. “No, seriously. This is the end of Donald Trump,” Moore said.

Yet Moore, a liberal activist who supported Bernie Sanders during the primary race, has demonstrated that he has something in common with Trump. He and the Republican presidential nominee are both willing to present controversial yet unsubstantiated claims as fact, even when doing so may be reckless.

Moore tells quite a story. He claims that Trump decided to run for president not because he thought he would win, but because he was “unhappy with his deal as host and star of his NBC show The Apprentice” and hoped to strengthen his negotiating position. The plan went horribly wrong, however, when NBC instead cut ties over Trump’s remarks about Mexican immigrants. By the time Trump realized he would actually become the nominee, running for president no longer looked so appealing to him. Moore then suggests that recent controversies caused by Trump on the campaign trail may be “all part of his new strategy to get the hell out of a race he never intended to see through to its end.”

For anyone horrified by the prospect of a Trump presidency and baffled that a reality-television star became the Republican presidential nominee, it must be comforting to imagine that even Trump never thought things would end up like this. That this was a ploy, rather than an earnest attempt to win the hearts and minds of American voters. But whatever Trump thought of his chances when he entered the race, and whatever his motivations, his campaign has clearly resonated. Moore acknowledges Trump's success, writing that the candidate reached the top of the polls among Republican voters as he “ignited the country, especially among people who were the opposite of billionaires.”

In the past, Moore has even warned that Trump should be taken seriously. “Nobody should treat it like it’s a joke,” he told Fox News host Megyn Kelly in May. And in July, Moore predicted on Real Time that Trump will win. Yet telling people that the candidate never intended to run a winning campaign, and may now be looking for an exit, nevertheless delegitimizes the idea of Trump as a serious candidate.

To dismiss the rise of Trump as unserious is to avoid reckoning with his very real popularity and what that says about the American electorate. Any theory that Trump is now actively sabotaging his campaign also leaves the impression that the candidate will be responsible for his own un-doing. If Trump’s political end looks like foregone conclusion, what’s the motivation for those who oppose him to volunteer and organize during the election, or even get out and vote?

It would be one thing if Moore made clear that the claims are speculation. But he says that he knows “for a fact” that Trump never actually wanted to be president without providing hard evidence. By the time he gets around to the idea that Trump is sabotaging his own campaign, however, he frames it as a theory. “Let me throw out another theory,” Moore wrote, before adding: “Maybe the meltdown of the past three weeks was no accident … Unless he is just ‘crazy,’ the only explanation for the unusual ramping up, day after day, of one disgustingly reckless statement after another is that he’s doing it consciously (or subconsciously) so that he’ll have to bow out or blame ‘others’ for forcing him out.” (Moore did not immediately respond to a request for comment. Hope Hicks, Trump’s spokeswoman, declined to comment on Moore’s claims.)

Trump himself is no stranger to presenting unsubstantiated and controversial claims as though they were fact. Consider, for example, Trump’s claims that when the World Trade Center collapsed during the 9/11 terrorist attacks, “there were people over in New Jersey that were watching it, a heavy Arab population, that were cheering as the buildings came down.” Sites like PolitiFact and The Washington Post fact checker repeatedly debunked his assertions, despite Trump’s insistence. But rather than sink his presidential prospects, these claims seemed to animate Trump’s core-base of supporters.

While Trump has taken aim at entire groups of people, Moore’s assertions focus on one person: Donald Trump. Claims made by the documentary filmmaker do not have the same potential to become the basis for American public policy, nor does Moore have the kind of platform or influence that comes with running a presidential campaign.  Moore also has a clear record of past statements that he believes Trump should be taken seriously and could win.

Finally, while Trump’s claims have been discredited by fact-checkers, Moore may yet end up vindicated. Nevertheless, their comments show a shared willingness across the political spectrum to present unsubstantiated claims as fact even when doing so could prove reckless. Moore, like Trump, is no stranger to controversy, and surely knows that gets attention. Many of the people reading Moore’s assertions may well be skeptical. Others may be willing to trust what he has to say—perhaps, just like Trump supporters, because they desperately want to believe that the inflammatory statements are true.