If you've seen Warren Buffett comment on social media about President Donald Trump's most recent tariff policies, the Berkshire Hathaway chairman and world's 4th-wealthiest person wants you to know it wasn't him.

"There are reports currently circulating on social media (including Twitter, Facebook and Tik Tok) regarding comments allegedly made by Warren E. Buffett. All such reports are false," reads a Friday statement from Berkshire.

The statement didn't mention Trump explicitly, but came shortly after the President shared a video on Truth Social that claimed he's initiating a 20% decline in stock prices "on purpose." (Trump later clarified that he is not engineering a sell-off.)

"And this is why Warren Buffett just said, 'Trump is making the best economic moves he's seen in over 50 years,'" the video's narrator says.

Buffett said no such thing. But he has gone on record over the years about both topics. Understanding how Buffett, widely regarded as one of history's greatest financial minds, thinks about tariffs — and about 20% drawdowns in the stock market — could help you navigate what has been a topsy-turvy market.

Here's what he's said.

Buffett on tariffs: 'The tooth fairy doesn't pay 'em!'

Buffett's most recent public comments on tariffs came in an early March interview with CBS News' Norah O'Donnell, in which he said that duties tend to contribute to rising prices.

"Over time, they are a tax on goods. I mean, the tooth fairy doesn't pay 'em!" Buffett said. "And then what? You always have to ask that question in economics. You always say, 'And then what?'"

Buffett likely has a good idea of what could come next.

For one, inflation. In 2018, when asked about Trump's first, less severe round of tariffs, Buffett said that duties — including the ones on aluminum and steel — had driven up costs at some of his constituent businesses.

Back then, Buffett said he saw the potential for tariffs to hurt consumer budgets. Though he noted the presence of inflation before Trump imposed tariffs on foreign goods, he said, "The tariff situation will aggravate it significantly."

The other potential ramification on Buffett's radar: a so-called trade war in which the U.S. and its trading partners get into a tit-for-tat of escalating import taxes, which could slow down the global economy.

In his March interview, Buffett called tariffs "an act of war, to some degree."

In 2019, amid tense U.S.-China trade tensions, Buffett was even more explicit. "If we actually have a trade war, it will be bad for the whole world … everything intersects in the world," Buffett said in an interview with CNBC. "A world that adjusts to something very close to free trade … more people will live better than in a world with significant tariffs and shifting tariffs over time."

Buffett on bear markets: 'An investor's best friend'

The S&P 500 has suffered losses in the wake of Trump's recent tariff announcement, but it has yet to officially close in bear territory — defined as a 20% fall from recent highs. If a bear does emerge, market analysts say it will likely be because investors are bracing for a trade war that could cause a global economic slowdown.

It wouldn't be the first time Buffett's navigated a worldwide recession. In 2008, in the midst of the global financial crisis and its associated bear market, Buffett penned an op-ed for the New York Times.

"The financial world is a mess, both in the United States and abroad. Its problems, moreover, have been leaking into the general economy, and the leaks are now turning into a gusher," he wrote. "In the near term, unemployment will rise, business activity will falter and headlines will continue to be scary."

"So ... I've been buying American stocks," he continued.

Buffett acknowledged that he had no idea what the stock market would do next. And indeed, after he published the piece in October 2008, the S&P 500 wouldn't find its bottom for another five months.

But as Buffett has pointed out over and over, businesses, en masse, have always found ways to innovate and increase their profitability over long periods, contributing to the historical upward trend in the stock market.

Many investors were hesitant to put their money at risk amid a financial crisis, Buffett said in 2008.

"But fears regarding the long-term prosperity of the nation's many sound companies make no sense," he wrote. "These businesses will indeed suffer earnings hiccups, as they always have. But most major companies will be setting new profit records 5, 10 and 20 years from now."

Buffett favors buying stocks when they're relatively cheap, as doing so boosts your returns over time. If you have money to invest and decades to realize compounding growth in your portfolio, it makes sense to continue investing in a diversified stock portfolio through downturns.

"In short, bad news is an investor's best friend," Buffett wrote in 2008. "It lets you buy a slice of America's future at a marked-down price."

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