Do you care about global warming? Yes? Liar. You still drive and fly. Your house lacks solar panels and windmills. You drive to super-stores where you buy food laden with air miles. You only recycle after Zac Goldsmith has been on television. And, speaking of Zac, his oh-so green proposal to charge for parking in out of town supermarkets had to be laughed off by George Osborne at the Tory conference. The shadow chancellor said he’d be off his trolley to do such a thing. Well, quite, because listen up Zac and all your eco-pals: nobody really cares about global warming, they just talk about it.

“The vast majority,” says Bjorn Lomborg, “are along for the ride. They’ve kids to pick up from day care, jobs to get on with, marriages to work on. This is a background phenomenon to many of these people.”

To statisticians and political scientists – Lomborg is both – what people say is trivial compared with what they do. Lomborg is, unquestionably, one of the most important living thinkers. Time magazine listed him in the world’s 100 most influential people; he was named as the 14th most influential academic in the world and a “young global leader”.

He doesn’t look like any of these things; he looks more like a tennis player or possibly a designer for Bang & Olufsen. In the lobby of a fashionable London hotel, he is wearing jeans, a polo shirt and black trainers. His hair is blond and the fixed gaze of his blue eyes is downright disturbing. His voice is deep and he is very talkative.

He is seen by the deep greens as the most appalling apostate – he was once a member of Greenpeace – and by the hard deniers he is seen as a secular saint: the man who pulled the rug out from under the whole climate change conspiracy. The latter will take particular delight in his latest book, Cool It: The Skeptical Environmentalist’s Guide to Global Warming.

He says that polar bears – the poster beasts for the greens – are not dying off as the ice pack melts; in fact, they are increasing in numbers. He accepts that rising temperatures will result in more heat deaths, but there will be far fewer deaths from cold. And Al Gore’s vision of a flooded Florida as sea levels rise by 20ft within the next century is treated with derision. The Kyoto accord on limiting emissions, meanwhile, will achieve almost nothing and cost billions.

But Lomborg is neither saint nor apostate. He believes global warming is happening and humans are causing it. He just doesn’t think it’s that serious. Moreover, he thinks – as does the US government – technology is the answer. Attempting to cut emissions is as futile as expecting the Tories to charge for supermarket parking.

“There’s a huge difference between what people say and what they do,” observes Lomborg. “Look at all the websites where you can take a flight and offset your carbon. Only about 1% do it. Likewise this goes for most politicians who say they will cut emissions dramatically. Blair said in 1997 that he’d reduce carbon emissions by 15%; we’ve seen an increase of 3% since then.”

This all began in February 1997. Lomborg was in Los Angeles and he read an article in Wired magazine by the late Julian Simon, an American right-wing thinker, trashing the eco-catastrophists. He went back to Denmark and with his statistics students set about the task of proving Simon wrong. Except for a few details, they failed. By the end of the year, he had concluded that Simon was right and the green case was a wild exaggeration. In right-on, PC, left-wing, green Denmark this was heresy. But Lomborg had been trained in heresy.

He was born in Copenhagen in 1965, the only child of a school-teacher mother and a father who was a musician and a priest in the liberal Catholic church. This is a strange blend of Christianity and theosophy.

“From a fairly early age I was used to being a little unusual. Denmark is a fiercely nonreligious country. In any questionnaire people tend to put religion under “hobbies”. But I would actually be a mass boy every Sunday, that kind of thing. I was brought up slightly weird, but I got used to the idea that just because you’re different doesn’t necessarily break you.”

He’s also gay, but he’s reluctant to include this as an aspect of his outsider status. “Well, I guess it taught me to be different in one more aspect and still be okay.”

He retains many vestiges of his upbringing and of PC Denmark. He is a vegetarian like his parents. He doesn’t drive a car, preferring to cycle round cities, and he retains a religious conviction. “I have this deep sense that there probably is a meaning to life and there probably is a God. But it’s not a big thing. It’s not as important as being a good person and a humanist.”

In 1998 he went into print in Denmark with his view on greenery, and in 2001 The Skeptical Environmentalist appeared in English. Next came Global Crises, Global Solutions. This was a collection of ideas from distinguished economists on the best ways to spend $50 billion on improving the human condition. Fighting global warming came low on all the lists.

The environmentalists were incandescent. His findings were assaulted on all sides. Scientific American magazine ran a feature in which scientists queued up to list ways in which he was wrong. The big accusation was that he was not an earth scientist. His defence was that he wasn’t doing earth science, he was simply analysing the figures on which the greens built their case.

A Danish government committee found him guilty of scientific dishonesty, a charge that was later withdrawn. “You were supposed to have good reasons for saying that, and they didn’t even provide a reason.”

Lomborg was further accused of being a shill for the Bush administration. After all, Bush and latterly Con-doleezza Rice insist that technology, not emissions controls, are the solution. Lomborg could have been writing the script. He acknowledges this but insists he retains his fundamental left-wing beliefs. He may tell the American government it is right about green technology, but he also tells it to divert resources to Aids and malaria in Africa. Does this really make him left wing?

“The way I see it, to be left wing is to care about people and making sure there are fewer inequalities and saying that what the market comes out with is not necessarily the right outcome. I actually thought I have always been historically left wing. This comes from the French revolution. These were the guys who believed in progress but also believed in facts against old-fashioned thinking. That’s what we are supposed to be about.”

His first two books put global warming in the context of other big problems, Cool It focuses solely on the environmental issue. His conclusion is that the best way to deal with warming is to set up an international research fund of $25 billion annually to seek solutions. This is, he calculates, about what the problem is worth. If the signs get worse, the sum could be increased. But the vast sums involved in cutting emissions are wasted because they are disproportionate to the problem, they will not work and they are politically futile.

I happen to think, on the basis of many other conversations, that he’s wrong about the seriousness of global warming. But I don’t doubt he’s right about the futility of emissions controls and the deep gulf that divides what people say and what they do.

Lomborg is plausible, persuasive and intellectually passionate. He regards most of the criticisms as pitiably weak on logic. There is, however, one criticism that cuts deeper. “The clear implication,” says the philosopher John Gray of Lomborg’s thought, “is that there is no need to restrain human ambitions in order to protect the environment; it can look after itself. In effect, this is a recycled version of the technological utopianism that’s always been popular in the US, and explains why it is so feted by big business.”

Lomborg looks startled when I put the charge of utopianism to him. He sees himself as a pragmatist. He believes in progress, but sees where it can go wrong. But the deep green and antihumanist intuition – most beautifully expressed by the American biologist EO Wilson – that we are utterly dependent on the earth and must, therefore, approach nature with reverence and humility, means nothing to him. He cycles only in the city, not in the forests. And if, in spite of your own hypocrisy, you feel uneasy about that then you are right to do so.

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