Imagine you are about to get on a plane with your family. A huge group of qualified airline mechanics approach you on the tarmac and explain they've studied the engine for many years and they're sure it will crash if you get on board. They show you their previous predictions of plane crashes, which have overwhelmingly been proven right. Then a group of vets, journalists, and plumbers tell they have looked at the diagrams and it's perfectly obvious to them the plane is safe and that airplane mechanics – all of them, everywhere – are scamming you. Would you get on the plane? That is our choice at Copenhagen.

Johan Hari: How I wish that the global warming deniers were right (Independent, 4.12.2009)