Daniel Johnson: Nigel, your book, An ­Appeal to Reason, has set off a very important and timely debate about the basis — both economic and scientific — for the consensus that has emerged on global warming. Were you surprised by the response to your book?

Nigel Lawson: The first thing that surprised me was the extreme difficulty in getting the book published. I had probably the number one agent in this country, and I’d published a number of books before, but he had the greatest difficulty finding a publisher at all. In fact he couldn’t find a British publisher and eventually had to go to an American publisher who has a subsidiary in London.

So that was the first surprise. After that, yes, I was pleasantly surprised by how much interest it has created, how well it is selling, how many people are reading it, and the huge number of supportive letters from all sorts of people — including very many scientists.

DJ: Oliver, are you surprised that Nigel’s book seems to have touched a nerve? Do you think that the debate on this subject in this country had become too one-sided, with the whole sceptical side of the argument being more or less excluded?

Oliver Letwin: Well, I think Nigel’s book — because it’s a good read, it’s well written, and because it’s very calm — is bound to be taken more seriously than if it were a diatribe. As we’ll discover as we proceed with the conversation, I don’t agree with many of the propositions in the book, but it’s good that there’s a book here which is serious and well considered; one that we can discuss and debate.