It is hard for me not to like James Lovelock. South London grammar-school boy, walker, mountain climber, scientist and admirer of Margaret Thatcher: what is not to like? But as the creator of the Gaia hypothesis, he is arguably one of the most influential and provocative radical thinkers of the last 50 years.Forty years ago he thought up the Gaia concept, and was attacked for what people misguidedly saw as a mystical idea, when it was a very scientific concept. He was described as a maverick, which he probably took as a compliment.He is doing it again, with his new book, The Vanishing Face of Gaia (Allen Lane, £20). In it he predicts that it is too late to reverse climate change. Worse, it is approaching a tipping-point, and will soon accelerate with cataclysmic consequences.