Warren Buffett says you could torture him, and he still wouldn't tell. The world's most famous investor, the Sage of Omaha, has chosen his successors, the duo who will take over at the helm of the Berkshire Hathaway business empire, but he's not saying who it is. He's being astute, as ever. Watch how power and influence drains away from a second-term president, for example, or from a British prime minister who declares he'll stick around for only a while longer. But it cannot stop Mr Buffett's legion of followers from guessing.
After all, Mr Buffett is 78.
The topic will no doubt be on the minds of many of the 30,000 Berkshire Hathaway investors who are expected to make the annual pilgrimage to Omaha, Nebraska, for the company's shareholder meeting in May. And Mr Buffett will no doubt point them to his latest statement on the matter – in his letter to them last month, when he said "all candidates currently work for or are available to Berkshire and are people in whom I have total confidence" – and then say no more.
Except that this time, there has been a big flurry of speculation about one name in particular, a certain Byron Trott, who just quit as head of the Midwestern office of Goldman Sachs, in Chicago. Mr Trott is "a rare investment banker who puts himself in his client's shoes", Mr Buffett has said, praise indeed from a man who is normally disdainful of "the priesthood of finance" and bankers out for a fast buck. Mr Trott is setting up on his own, creating a new merchant bank called BDT Capital Partners, and Mr Buffett likes him so much he is buying into the company.
The two men share a Midwestern background and sensibility, hailing from a part of the US that usually spurns the flash of the West Coast or the cut-throat instincts of the East. It is in these roots that you can find the origins of Mr Buffett's own homespun wisdom, and they are why he has not ever moved from his native Omaha, despite turning Berkshire into one of the world's largest companies, spanning insurance, energy and consumer goods, and with stock market investments in some of the most famous brands on the planet.
In Chicago, Mr Trott is most famous as a workaholic, jetting around the 13 states in his purview and leaving voicemail messages for clients in the middle of the night. Aged 50, after more than half a lifetime at Goldman Sachs, he is finally going to tap an extraordinary Rolodex of uber-rich contacts for himself rather than the firm.
Investment bankers are the diplomats of finance, always searching for a deal that will make all the parties happy, and Mr Trott is the quintessential middleman. He is well-connected, discreet and eminently trustworthy, and he speaks his mind.
His first job for Goldman was as a stockbroker for wealthy clients, a job that put him into the orbit of the wealthy families of the Midwest – the Mars and Wrigley families, whose confectionery companies he helped to merge last year, or the Pritzker family behind the Hyatt hotels chain, on whose board he sits.
Whether it is watching the Chicago Bears American football team from a box at the city's Soldier Field, or advising the Art Institute of Chicago how to manage its funds, or sitting on the board of trustees of his alma mater, the University of Chicago, he intertwines fun and philanthropy with hobnobbing with the great and good. When he stumped up $14,000 (£10,000) for tickets to the David Letterman show and a posh dinner in New York, it was all in aid of one of Chicago's most prestigious ballet companies.
Even his political donations look astute. Whilst he has given most money to the Republican party, he has attended fundraisers for politicians on both sides of the aisle and of both hues in presidential races. Perhaps most notably, he was backing Barack Obama as far back as 2003, a year before the wannabe Senator for Illinois had made that career-changing appearance at the Democratic convention.
His one piece of flash is a giant home on the shore of Lake Michigan, built from scratch to a Robert Stern design. The three-acre parcel of land alone cost him $11.4m, and the house boasts a pool, a boathouse and numerous porches.
So far, so banker. What marks him out, at least according to Mr Buffett, is his smarts, an ability to see deals from both buyer and seller's point of view. For Mr Trott, unlike most, has a business background of his own, stretching back into his teens. At about the same age as Mr Buffett was hawking pinball machines to local businesses, the young Byron Trott borrowed $30,000 from his father to launch a clothing shop for the teenagers of his native Union, Missouri, a small town near St Louis. "There was no local place for kids to buy clothes other than Wrangler jeans and overalls," he would say later. At university, he did it again, selling sportswear.
Mr Buffett became close to him earlier this decade, after Mr Trott brought Berkshire Hathaway a trio of acquisitions that turned out very nicely for all sides, after which the Sage of Omaha wrote: "He understands Berkshire far better than any investment banker with whom we have talked and – it hurts me to say this – earns his fee."
The Berkshire faithful measure the fortunes of Mr Buffett's likely heirs according to the amounts of praise he lavishes on them in his long annual letter, so Mr Trott has been on the radar since that mention in 2003. He is intensely private and protective of his family, though, so may well prefer to stay behind the scenes, unlike the gregarious Mr Buffett. Much could also depend on the progress of his new business venture, prospects for which look strong.
And we should end on a word of wisdom from the Sage's most recent letter. "I also want to assure you that I have never felt better. I love running Berkshire, and if enjoying life promotes longevity, Methuselah's record is in jeopardy."
The contenders: Four who could take over Buffett's mantle
When Ajit came to Berkshire in 1996, Mr Buffett wrote: "I did the logical thing: I wrote to his parents in New Delhi and asked if they had another one like him at home."
Mr Jain runs Berkshire's reinsurance arm, one of the world's biggest insurers of insurance companies, with a team of just 31 people.
NetJets is one of Mr Buffett's favourite firms, offering fractional ownership of private jets to not-quite-super-rich Americans. Mr Santulli invented the concept, founded the company and still runs it under the Berkshire umbrella, after selling out to his most famous customer.
The 52-year-old David Sokol is one of the most feted corporate bosses in the US, having been chief executive and now chairman of the energy firm MidAmerican since 1989, turning it into one of the most powerful in the land. His charity work mentoring students endears him to Mr Buffett.
Chief executive of Geico, Berkshire's insurance arm, Olza "Tony" Nicely is bookies' favourite to take over as chief executive of the parent. He is loyal to Geico to the point of obsession, and has a youthful ambition despite his 64 years. Mr Buffett notes that "Tony feels Geico is just getting started".