I do say how we should deal with it if the science is right. But the science is very uncertain, and people who say that it is certain are either ignorant or liars. But man has always adapted to changes in the climate. And that is perfectly practical, especially when in many parts of the world a few degrees warmer is actually an improvement. In other parts it’s not, of course, but you can pick up the benefits in those parts that benefit, and you adapt to minimise the losses in those other countries. If there are problems in some of the poorer countries, we must help them adapt through our overseas aid programmes. That is far cheaper than severely damaging our economies by moving to much higher-cost energy.

There is a big hoo-ha now about high energy costs. The Government’s policy on global warming — and I regret to say it’s a policy supported by the official Opposition — only makes sense if energy prices are far higher than they are today. So it is a bit illogical to complain about the high price of energy now, when in fact their whole policy on so-called climate change is to push up the price of energy.

OL: The only thing Nigel said that I agree with is that it’s absurd to suppose that everything should be linked to climate change, or that nothing should be said about biodiversity or contamination. Clearly all those things matter enormously, as does the beauty of our natural environment.

Let me start with Nigel’s proposition that it is hugely expensive to address this problem by mitigation rather than adaptation, which in a way is the central thesis of the book. There are reasons for aiming towards a low-carbon economy which have to do with carbon, but there are also reasons which have to do with energy prices and energy security. I think they all point in the same direction.