I like to think I live in the real world, and I’ve lowered my expectations accordingly. I don’t expect Members of Parliament to dress like Anthony Eden, although navy pinstripe suits make men look serious and unexpectedly sexy.

I don’t expect BBC broadcasters to dress like Alistair Cooke or Cary Grant, two Englishmen who understood the politics of dress. But a couple of weeks ago, when Evan Davis travelled to Omaha, Nebraska, to interview ‘the World’s Greatest Money Maker’, I’d have thought he’d at least put on a tie. Surely meeting one of the world’s most remarkable men wasn’t an ‘I’m too cool/clever/boyish to wear a tie’ occasion? But there he was, meeting Warren Buffett, looking like a high-school baseball coach on a losing streak.

Of course, the plain-dealing Warren Buffett was wearing a tie, a wordless sign of respect for the BBC and its tieless ambassador. The tie provides gravitas. It’s a sign of courtesy. It’s the English speaking man’s version of the French vousvoyez vs tutoyer. You don’t presume to use the informal tutoyer to a distinguished person who is granting you the favour of an interview. You vousvoyer them until they request otherwise.

Not that the 79-year-old Mr Buffett looked offended. With princely manners, he was the one who apologised. ‘I can’t give you too long because, from an actuarial standpoint, I have only about 4,000 days left on the Earth and I’m trying to keep various activities in proportion.’

In an age when bankers are viewed with venality, the world’s richest man seems free of the solipsism and crass speculations of those money-grubbing prospectors. His ‘aw shucks’ persona distracts you from the Masters degree in Economics from Columbia University and a lifetime of hard work. The Huck Finn of investing insists that he was just ‘lucky at birth’.

Hundreds of articles and books have been written about Mr Buffett’s ‘Ten Secrets to Wealth and Life’ and the BBC programme was structured around eight of them, including: Invest, don’t speculate; You don’t have to diversify; Don’t get into debt; and Give it away. He makes it sound easy, but there’s more to the formula. It’s who he is.

The world’s richest man lives in the same house in Omaha that he bought in 1958 for $31,500. He drives a Cadillac that he got at a reduced price because it was ‘hail damaged’. His only extravagance is a private jet he sheepishly named The Indefensible.

He plays bridge 12 hours a week on his computer and with Bill Gates whenever they get together. He backed Barack Obama for president, insisting that John McCain would have to have a ‘lobotomy’ for him  to change his endorsement. In 2006, he gave $30 billion to the Bill and Melinda Gates Foundation, the largest charitable donation in history. He doesn’t believe in passing great fortunes from one generation to the next: ‘I want to give my kids just enough that they feel that they can do anything, but not so much that they would feel like doing nothing.’

Some things make Mr Buffett furious. Bankers who helped create the ‘the economic Pearl Harbor’ getting bonuses while people are losing their jobs and homes. The huge hunk of American assets now in the hands of foreigners. Writing to shareholders in 2005, he warned that Americans who take pride in being an ‘ownership society’ will wake up and find that they’ve become a ‘sharecropping society’.

But Mr Davis never really bonded with Mr Buffett. Never found out why he works so hard to make money and then gives it away. Never asked tough questions, such as why Kraft, a company he controls, is circling Cadbury like buzzards. My theory? If Mr Davis had been wearing a tie, he’d have had the authority to ask more penetrating questions. But heck, it’s never too late to learn that it’s the tie that binds.

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