What does it mean to say that someone will change the world? Not long ago, the answer would have been straightforward. World-changers are rulers who invade foreign countries, scientists who revolutionise human knowledge, artists who come up with striking new visions of life. Today, however, the concept feels less clear-cut. It is a curious feature of modernity that, while the world we live in is changing at a dizzying pace, those responsible for changing it are becoming harder to identify. Politicians often appear to be mere figureheads, buffeted by other forces. Meanwhile, those with genuine power - media and business tycoons - affect our lives in nebulous, hard-to-quantify ways. The evidence of scientific progress is all around us, but who will the Einsteins of the 21st century be? As for writers and artists changing the world - the very idea seems faintly ridiculous.
Nevertheless, the New Statesman is being bold. In selecting our ten world-changers, we have tried to reflect the ways that power and influence operate in our complex, interconnected world. We have chosen only one out-and-out politician: Barack Obama, potential saviour of the US Democrats. Our other candidates are drawn from an eclectic range of fields - sport, quantum physics, pharmaceuticals, the environment, activism. Our list is not supposed to be definitive; it is intended, rather, to provoke discussion on important issues.
And it is intended to offer hope. Given that the present is characterised by relentless violence and carnage, manmade or otherwise, it would have been easy to side with the pessimists and produce a largely negative list (although finding those who will make the world worse is, almost by definition, harder than finding those who will do good: who can say who the next Osama Bin Laden will be?). But we didn't want to be gloomy. And so here are ten people who, in a hard-headed and practical way, are helping to make the world a better place.