Bill Gates now devotes much of his time and money to philanthropy
After interviewing many of the world's richest men, HARDtalk presenter Stephen Sackur ponders the qualities that those billionaires have in common.
Bill Gates may be a billionaire 50 times over, but he is struggling to raise a five-dollar smile. He arrives for our interview with all the enthusiasm of a man about to have his toenails forcibly removed.
But then the cameras roll. Gates powers up, his eyes engage. For half an hour, the founder of Microsoft radiates passionate intelligence.
We are in Geneva for the UN's World Health Assembly, at which Gates is a keynote speaker. He tells me about the progress being made to vaccinate the world's poorest children against many of the most harmful infectious diseases.
The Bill and Melinda Gates Foundation has pledged $10bn (£6.15bn) to scientific research and immunisation programmes to make this the "decade of vaccines".
A billion gives you economic, social and political leverage
For those who idly wonder about the difference between being plain rich and being vastly, unimaginably wealthy, here is an answer. Billionaires (and there are more than 1,200 of them, according to the latest
Forbes Rich List
) get to think and act on a global scale.
A fortune of $50m will buy luxury homes, fancy cars and a lifetime of ease, but it will not guarantee you a seat at the top table of the world's power elite.
But a billion gives you economic, social and political leverage, should you care to exploit it.
Bill Gates knows that better than most. A billionaire before the age of 32, he's had 25 years to make sense of his fabulous wealth.
For him, and for his wife Melinda, meaning has come in the form of philanthropy. Their foundation has already poured $25bn into public health and development projects around the world.
WORLD'S 10 RICHEST PEOPLE
Carlos Slim and family: $74bn, telecoms
Bill Gates: $56bn, computing
Warren Buffett: $50bn, investor and industrialist
Bernard Arnault: $41bn, luxury brands
Larry Ellison: $39.5bn, computing
Lakshmi Mittal: $31.1bn, steel
Amancio Ortega: $31bn, fashion
Eike Batista: $30bn, mining and oil
Mukesh Ambani: $27bn, oil and gas
Christy Walton and family: $26.5bn, Walmart
Source: Forbes Rich List
As his ambitions grew, so did his determination to draw others in. His first convert was Warren Buffett, America's most successful investor, who pledged to drip-feed most of his own immense fortune into the Gates Foundation.
Last year Gates and Buffett devised a Giving Pledge and sought public declarations of support from the world's super-wealthy elite. Sixty-nine individuals have so far promised to give at least half of their assets during their lives or upon their deaths.
"We think a lot of people miss the opportunity to do philanthropy; to do it younger, to get more engaged, to give a higher percentage of their money to it, and part of that is that it's not that easy to learn," says Gates.
"Everybody has a cause, but who do you talk to that has had a similar experience and can really share that overall it's a fun, positive thing."
Gates has recently been to China and India to spread the giving word.
But does it translate? "A first-generation fortune is the most likely to be given away, but once a fortune is inherited it's less likely that a very high percentage will go back to society," he says.
In China, it's all first-generation fortunes, he says. In India, "a lot are".
Reports from Beijing suggest there was initial reluctance to attend a "philanthropy dinner" with Gates. With self-made fortunes a new phenomenon, there was a fear he would expect embarrassingly public pledges of cash.
Cooking, not cuisine
There is an ascetic quality to the Microsoft founder which marks him out from other members of the international billionaires club.
One of his staff tells of a recent posh dinner given for Gates in Paris. "It was typically French. Incredibly elaborate food. Bill hated it. As soon as we got into the car he asked for a burger."
Such low-key style is not shared by other billionaires of my experience.
Australian billionaire Clive Palmer supplies minerals for China's economic boom
Take Clive Palmer, the larger-than-life Australian mining magnate whose ownership of vast reserves of iron ore and coal have made him one of his country's richest men.
Palmer cites his friend, the late Ted Kennedy, as an inspiration for his philanthropy. He has given tens of millions of dollars to charitable causes.
"If God gives you a job on Earth and... the ability to control a lot of wealth, you've got to use it for the benefit of the country and the people in the community," he told me.
But he also pours money into his football team - Gold Coast United - and a string of racehorses.
And unlike Gates, Palmer splashes cash in the political arena. He's one of the biggest financial backers of Australia's opposition Liberal Party, and put millions into the campaign against a proposed supertax on mining companies.
And then there's Russia, home to a cluster of billionaires who made mountains of money amid the economic chaos that followed the collapse of communism. The Gates-Buffett Giving Pledge hasn't yet been adopted with enthusiasm by the oligarchs.
Russian billionaire Alexander Lebedev has built an international media empire
A few months ago Alexander Lebedev, former Soviet intelligence officer, billionaire investor and now proud London newspaper proprietor, journeyed to the HARDtalk studio. This is a man who uses his wealth as a form of protection.
His newspapers in Russia and in London cost him money, but they give him a profile and international connections which are priceless in the unpredictable world of Moscow politics.
"I find my ways to defend myself," he says.
Likewise, charitable donations to Russian arts institutions also positively project the Lebedev "brand".
Cynical? No, just realistic. Self-made billionaires are the highest of high achievers. Ambition and ego aren't absent, even when they're giving their money away.
Whether it be researching a new vaccine, or buying a football team, billionaires want results. After all, these are people used to winning.
You can watch the full interview with Bill Gates on BBC World News on Wednesday 18 May 2011 at 0330, 0830, 1530 and 2030 GMT and on BBC News Channel at 0430 BST on Wednesday 18 May 2011 and at 0030 BST on Thursday 19th May 2011.
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