The challenge is not, ‘Either we believe in global warming and rescue the planet or we all die.’ It is largely a choice between how much action to take now and how much in the future; and a choice between preventing or adapting to it. The science is still young. Some people take uncertainty as a reason to act, others take it as a reason to proceed slowly. Future generations will have the benefit of greater scientific knowledge, better technology, and greater wealth… . . The range of views expressed at our conference suggests that the debate is far from being over, and that there is still time for much-needed rational discussion.