A couple of times in the course of my lunch with Professor James Lovelock, I catch our waitress cocking an eyebrow at me in mild surprise. As instructed by Lovelock’s publisher, I asked for the quietest table in the restaurant. But, between us, my guest and I manage to make enough noise – mainly hoots of laughter – to attract the attention of other diners.

If they could hear the rest of our conversation, they would be even more surprised. ”Humanity will be reduced to a few breeding pairs.” ”An enormous food shortage will kill off most people.” ”Watch the Dutch. Half of northern Europe will be under water, and there’s Holland behind a 10ft surrounding wall carrying on business as usual.” More laughter. Lovelock is a very jolly prophet of the apocalypse.