The idea that we are one step from calamity is as old as history itself. Every step on the road of progress has been countered by those who think that we should keep to a primitive lifestyle that they claim is compatible with nature. But despite the fact they've been proved wrong, the pessimists are undeterred by their abysmal record. Today, industrialization, genetically modified crops, scientific medicine, nuclear power, and the car are held up as harbingers of doom. Politicians and pressure groups play on this same basic fear. They scare us with tales of an inevitable global warming catastrophe blamed on CO2 emissions, and they stoke the fires of terror that an obesity epidemic will kill all our children. But will pesticides kill off life in our oceans, will chemicals in food poison us all, and invisible rays from power cables and mobiles kill us with cancer?