Participating in a public Q&A session with Bloomberg's editor in chief on Thursday, Justin Trudeau was asked what he'd learned about Donald Trump in his three months of dealing with the American president.

The prime minister thought about this for a second or two.

"I've learned that he listens," Trudeau said, seated on a stage at Toronto's Art Gallery of Ontario.

This is possibly one of the nicest things anyone has said about Trump's presidency.

What followed was an artfully frank assessment of the president. The prime minister critiqued his counterpart even as he flattered him, and laid out the challenge of dealing with the American leader even as he tried to strike an optimistic chord.

Trudeau on what he has learned about Trump so far 1:13

"He is a little bit unlike many politicians," Trudeau said, pausing and then smiling as he realized what he'd said.

"I'm just going to leave that sentence right there."

The crowd chuckled.

"But in that, as politicians, we're very, very much trained to say something and stick with it," Trudeau continued.

"Where he has shown that, if he says one thing and then actually hears good counter-arguments or good reasons why he should shift his position, he will take a different position, if it's a better one, if the arguments win him over."

Where Trump will be tomorrow

That is most definitely one way of looking at Trump's first 90 days as president.

Here, courtesy of Bloomberg's own Albert R. Hunt, is another.

"It's that he never had real beliefs or core convictions other than his commercial interests and personal self-regard," Hunt wrote this week, reflecting on a dizzying series of recent reversals.

"No one can say where Trump will be tomorrow. Beyond his philosophical vacuum, he doesn't know much."

As he proceeded with his assessment, Trudeau made a neat concession to the problem of a politician who says all sorts of things but does otherwise.

"And I think there's a challenge in there for electors," he said, "but there's also an opportunity in that for people who engage with him, to try and work to achieve a beneficial outcome."

U.S. President Donald Trump, left, and China's President Xi Jinping walk along the front patio of the Mar-a-Lago estate after a bilateral meeting in Palm Beach, Florida, U.S., April 7, 2017. Xi apparently managed to change Trump's view about China's potential role vis-a-vis North Korea in 10 short minutes. (Carlos Barria/Reuters)

American voters might be at sea, but for a Canadian prime minister this is the best hope when presented with something like Trump's decision on Tuesday to suddenly attack Canada's dairy policies as a "disaster" for American producers. That however adamant Trump seems in declaring a fight on Tuesday, he can be mollified with a phone call (or sternly worded letter) on Wednesday.

Trump himself has suggested he's so persuadable, telling the Wall Street Journal that a 10-minute conversation with the Chinese president was enough to change his mind about China's relationship with North Korea. A meeting with corporate executives reportedly convinced Trump he was wrong to label China a currency manipulator.

Trump attacks Canadian lumber

No sooner had Trudeau's session in Toronto finished than Trump appeared on camera in Washington ripping the Canadian lumber industry.

"Emerging pattern-Trump attacks-Trudeau sits in the corner & hopes he doesn't really mean what he's saying??" the NDP's Tracey Ramsey quickly tweeted.

Emerging pattern-Trump attacks-Trudeau sits in the corner & hopes he doesn't really mean what he's saying?? <a href="https://t.co/iPJEdFqAVP">https://t.co/iPJEdFqAVP</a> —@traceyram

The good news is Trump might say something else entirely tomorrow.

Because whether or not Trudeau can fairly be described as sitting in the corner, there is scant evidence Trump is particularly committed to the things he says. The Washington Post's Fact Checker has declared him "king of flip-flops." Last November, Politico counted 15 reversals in Trump's first 15 days as president-elect.

"In a world where candidates have lost elections over a single flip-flop, Trump has turned the self-contradiction into an art form," Michael Kruse and Noah Weiland wrote for the magazine during the campaign last May.

Having defied the laws of politics to win the presidency — surviving scandals that would have doomed other candidacies, saying things that would have been considered beyond the pale — there is little reason to expect anything like normalcy now.

Changing Trump's mind about trade

That history of contradiction undermines any suggestion Trump is merely confronting the learning curve that all new presidents experience. And while all governments deviate to some extent or another from their campaign commitments, Trump seems to possess a unique willingness to change course.

On the one hand, that might mean he suddenly decides to bomb Syria. On the other, it could have him deciding to stay in the Paris accord on climate change.

To what degree are his positions now determined by whoever is advising him? How often does it depend on who speaks to him last?

Maybe Trump really is willing to be convinced by substantive, well-informed arguments. But, in the meantime, how many unnecessary tempests will he stir? And on what points might his supporters demand he hold firm?

Chances are the president isn't angling for a trade war with Canada; that this is rhetorical posturing for an American audience. Or that, even if he is fixing for a fight, Trudeau can talk him out of it.

Unless, of course, he decides to listen to someone else who's telling him differently.