Warren Buffett told CNBC on Friday he would be "surprised a lot" if stock prices around the world fell 50 percent from their current levels in the near future. He predicted there will be another financial crisis "someday" in the years ahead that will shock financial markets, but he doesn't think it will happen anytime soon.

"Humans will behave in crazy ways, both on the upside and the downside in the next 50 years. It's very unlikely they do it in the next few years because after something like 2008, once they get out of the emergency room, they're a little more careful for awhile." During an appearance on CNBC's "Squawk Box," Buffett told 58-year-old host Joe Kernen that he will live to see the Dow at 100,000. "I won't, but you will," the 83-year-old Berkshire Hathaway chairman said.

Buffett pointed out that Berkshire stock has dropped 50 percent four times in its history, but always recovered. After reading an preliminary version of former Treasury Secretary Tim Geithner's upcoming memoir, Buffett said he now thinks his characterization of the 2008 crisis as an "economic Pearl Harbor" looks understated. But the U.S. did recover and he believes "this country will come through anything." Even if the U.S. hadn't guaranteed money market funds, preventing a total shutdown of the economy, "the United States would still come back. We would come back if we had some massive attack from abroad. ... The farms don't go away, the productive capacity doesn't go away, human ingenuity doesn't go away, the desire of people to live better in the future and for their kids doesn't go away."

Warren Buffett Adam Jeffery | CNBC

Buffett said he's been bullish on the U.S. economy since the fall of 2008, but he doesn't expect it to rapidly accelerate this year. Instead, he thinks it will continue its slow upward trajectory.

He said he'd advise people to "stay away" from bitcoin because the cryptocurrency is a "mirage" without any intrinsic value, although it's an efficient way to transfer dollars.

Buffett also said Berkshire Hathaway has "almost" eliminated its catastrophe insurance in the U.S. because rates have dropped too much.

"The rates came down dramatically, and we do not regard the exposure as having come down dramatically," Buffett said. Berkshire is still writing policies in Asia. Asked about the controversy over faulty ignition switches in General Motors cars, Buffett said CEO Mary Barra has a "new chance" because she just started in the post but the company needs to tell the truth and act quickly to fix any problems. He said his advice is to "Get it right, get it fast, get it out, get it over, but get it right first."

Buffett appeared on CNBC with Dan Gilbert to promote their "Quicken Loans Billion Dollar Bracket Challenge with Yahoo Sports" in which anyone who correctly predicts the outcome of every game in the NCAA basketball tournament will win $1 billion. (Read more: Buffett insures billion dollar bracket madness) Buffett's Berkshire sold the insurance that will fund the prize in the extremely unlikely event someone wins it. Odds against winning can't be calculated precisely but estimates involve the word "quintillion."