Russian maths genius Grigory Perelman, who declined a prestigious international award four years ago, is under new pressure to accept a prize.
I don’t want to be on display like an animal in a zoo. I’m not a hero of mathematics. I’m not even that successful; that is why I don’t want to have everybody looking at me.
A US institute wants to give him $1m (£700,000) for solving one of the world’s most complex mathematical problems, the Poincare Conjecture.
But it is unclear whether Dr Perelman, a virtual recluse, will pick it up.
A children’s charity in St Petersburg, where he lives, has urged him to take the money and give it to charity.
Dr Perelman, 43, has cut himself off from the outside world for the past four years, living with his elderly mother in a tiny flat said by neighbours to be infested with cockroaches.
In an open letter on its website, the Warm Home charity called on Dr Perelman to give the cash equivalent of the US Clay Mathematics Institute’s $1m Millennium Prize to Russian charities.
It suggested that the mathematician had already made an ethical point by turning down the Fields Medal, the world’s highest prize in mathematics, in 2006.