Leading article: Humility in an age of celebrity

For a century the conjecture of Henri Poincaré, a distinguished French topologist, remained just that - a conjecture. Then along came a young mathematician from St Petersburg called Gregori Perelman and the conjecture was proved. In a series of devastating scientific papers published on the internet in 2002 and 2003, Perelman appeared to have solved a mathematical mystery that had defied explanation since Poincaré first put it forward in 1904.

But it took a further two years of hard work by a number of independent mathematicians to show that Perelman was right. In this instance, as in other areas of mathematics, a proof is not considered definitive until others have had a good go at punching holes in the logic. Yet the combined efforts of mathematical experts from America and China failed to find any fundamental flaw in Perelman's approach. As a result, earlier this year the Russian was awarded the Fields Medal, the mathematical equivalent of a Nobel Prize.

What made the story a sensation, however, was that he was also awarded a separate prize of $1m by the Clay Mathematics Institute in Cambridge, Massachusetts - an award that, like the Fields Medal, Perelman turned down. In this age of reality realism, when ordinary people strive for extraordinary success and the publicity and financial rewards that go with it, Perelman's decision to seek undistinguished anonymity looks as strange as the conjecture itself.

What little we know of the man is that he spent three years in the United States before returning in 1995 to his native St Petersburg. For the next seven years he remained mostly incommunicado before posting the first of his three papers on the internet in November 2002. In 2003, Perelman revisited the United States to lecture on his work. In one lecture hall at Princeton University sat Andrew Wiles, the Englishman who solved Fermat's Last Theorem, and John Nash, the Nobel Laureate whose life inspired the film A Beautiful Mind.

After returning to Russia, Perelman seemed to retreat further into his his shell, refusing interview requests and shunning the publicity everyone wanted him to have. We should see this as a strength rather than a weakness.

Perelman is an undoubted genius, and evidently finds life in the public glare a hazard to be avoided rather than a pleasure to be embraced. His mathematical efforts should be applauded for the inspiration they have given to others. But his personal humility should be applauded equally in these times of 15-minute bursts of fame and doubtful glory.