Buffett's first thought was, "What do I tell my dad? This is terrible." But, he says, "it turned out to be the best thing that ever happened to me."

"They told me I was to get interviewed in a place near Chicago," the iconic investor recounts in HBO's " Becoming Warren Buffett ," which debuted Monday. "I got there and they interviewed me for about 10 minutes and said: 'Forget it. You're not going to Harvard.'"

After graduating from the University of Nebraska in three years, Warren Buffett applied to Harvard Business School .

The rejection opened the door to Columbia. Later that summer, while looking through a catalog for Columbia Business School, Buffett recognized the names of two professors: Benjamin Graham, the father of value investing, and David Dodd.

"I had read this book ["Security Analysis"] by the two of them, so I wrote them a letter in mid-August," Buffett says. "I said, 'Dear Professor Dodd. I thought you guys were dead, but now that I found out that you're alive and teaching at Columbia, I would really like to come.'

"And he admitted me."



"Ben was this incredible teacher. He was a natural and he drew us all in," Buffett says of Graham. "It was like learning baseball from a fellow who was batting .400. It shaped my professional life."



It was Graham who taught him "the two rules of investing" that Buffett has lived by throughout his massively successful career.

"Rule number one: Never lose money," Buffett says. "Rule number two: Never forget rule number one."



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