With an estimated net worth of $80 billion, Bill Gates is the richest guy in America, and Warren Buffett is the second-wealthiest at $67 billion.
And, although Buffett is 26 years older than Gates, the two are clearly the closest of friends.
As a team, they started a campaign asking the world's richest people to give their money to charities. They lobby Congress as a team. They criticize flat taxes as a team. They read classic business books as a team.
They play ping pong, they chill out in China together, and they throw newspapers as part of a strange tradition at the Berkshire Hathaway annual meeting.
Buffett trusts Gates: He gave the Bill and Melinda Gates Foundation $2.1 billion.
Gates trusts Buffett: He says that his dialogue with Buffett has been "invaluable" to his career.
But they didn't want to have anything to do with each other when they first met through Washington Post editor Meg Greenfield on July 5, 1991.
It's the stuff of bromantic comedy.
Greenfield — a family friend of the Gateses — was cruising through Seattle with Katharine "Kay" Graham, the Post publisher who presided over Watergate, and Buffett was along for the ride since he was BFFs with Graham and Berkshire Hathaway held a stake in the Post.
The plan was to hang out with Bill Gates Sr., his wife Mary, and that software mogul son of theirs, Bill Gates.
Buffett was nonplussed.
"While we're driving down there, I said, 'What the hell are we going to spend all day doing with these people? How long do we have to stay to be polite?"he tells the Financial Times.
Buffett thought he'd want nothing to do with the younger Gates — computers were like Brussels sprouts to him.
And Gates remembers complaining to his mom about meeting Buffett.
"What were he and I supposed to talk about, P/E ratios?"he recalls in a Fortune column. "I mean, spend all day with a guy who just picks stocks?"
But Gates was excited about meeting Graham — he was intrigued by the Post and its history.
Resigned to his fate, Gate said that he would stay for a few hours to chat with his elders, and then he'd helicopter back to the Microsoft headquarters to crush it at the office.
Then Graham, Greenfield, and Buffett arrived.
After a few introductions, Buffett and Gates started talking about the changes in the newspaper business. Then Buffett started asking Gates about his industry.
"If you were building IBM from scratch, how would it look different?" he asked. "What are the growth businesses for IBM? What has changed for them?"
Then Gates told Buffett to buy two stocks: Intel and Microsoft.
They were immersed in conversation. The bromance was blooming.
In recalling that first meeting, Gates says that he was struck by a few things. First, Buffett "asked good questions and told educational stories." Second, he'd "never met anyone who thought about business in such a clear way." Third, Buffett taught him a fun mental exercise.
"On that first day, [Buffett] introduced me to an intriguing analytic exercise that he does," Gates says. "He'll choose a year — say, 1970 — and examine the 10 highest market-capitalization companies from around then. Then he'll go forward to 1990 and look at how those companies fared. His enthusiasm for the exercise was contagious."
Gates was hooked. Before the Oracle left that day, he agreed to fly out to Nebraska to see Buffett's beloved University of Nebraska Cornhuskers dominate a college football game.
Now they have fun together all the time, whether lobbying Congress, fighting disease, or just hanging out and talking about "Business Adventures," as geniuses do.
In Buffett, Gates found a mentor.
"When Melinda and I started our foundation, I turned to him for advice," Gates says. "We talked a lot about the idea that philanthropy could be just as impactful in its own way as software had been. It turns out that Warren’s brilliant way of looking at the world is just as useful in attacking poverty and disease as it is in building a business. He's one of a kind."
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