… is from page 347 of Matt Ridley’s profoundly important 2010 book, The Rational Optimist:
Remember I am not here attempting to resolve the climate debate, nor saying that catastrophe is impossible. I am testing my optimism against the facts, and what I find is that the probability of rapid and severe climate change is small; the probability of net harm from the most likely climate change is small; the probability that no adaptation will occur is small; and the probability of no new low-carbon energy technologies emerging in the long run is small. Multiply those small probabilities together and the probability of a prosperous twenty-first century is therefore by definition large. You can argue about just how large, and therefore about how much needs to be spent on precaution; but you cannot on the IPCC’s figures make it anything other than very probable that the world will be a better place in 2100 than it is today.