We remember Adam Smith for his intuition of the invisible hand that enables self-interest to work for the common good. Over 200 years later we face a similar paradox. We know that the Earth is a benign place for life and has been so for most of its history, so how have selfish genes allowed the evolution of an altruistic planet? It is easy now to see how Darwinian natural selection leads to the evolution of fit organisms, but how can the common good for all life also evolve by natural selection? What we have discovered is that as our planet evolves, it keeps its climate and its chemistry always fit for life. The invisible hand that regulates the earth system operates through feedbacks, negative and positive, between its living and non-living parts. But this knowledge, Gaia theory, is still the domain of specialist science and is not yet understood or applied in the public world. In politics, it took a long time before we recognised that feedback from market forces could not be ignored; I suspect that we face a similar slow learning process about our relationship with the Earth. Meanwhile we are still trying to shape it to our needs and we ignore, even disable, its own powerful guiding hand.
It seems likely that we will face huge environmental disturbances as this century advances. But there are no certainties here. There may be little or no harm from global warming; we might even undo some of the damage we have done, or be rescued by a natural event, such as the eruption of large volcanos. This would put the Earth back on course towards the next glaciation and leave us free to continue burning fossil fuel. But we would be unwise to continue with business as usual and expect something to save us from the revenge of our outraged planet.
European politicians appear to accept the near inevitability of global warming but, oddly, turn to the green movement and its lobbies for guidance, more than to scientists. I see myself as a green but I speak as a scientist. Despite their good intentions, the majority of the greens are more concerned about the trivial risks from chemicals and radiation than about the serious risk of adverse global changes; consequently, their advice to governments is flawed.
Two centuries ago, in Adam Smith's time, there were fewer than a billion of us and nothing we did significantly harmed the Earth. As population and industry grew, we did not notice, until recently, that we were changing the atmosphere of the Earth. We ignored the fact that we depended on the other lifeforms not only for food but for the air we breathe and climate we enjoy. Because we are by nature self-interested, we took it all for granted. The error of the modern green movement is its self-indulgence, its hypochondriac obsession with personal hazards to health such as pesticide residues and other unwanted chemicals in foodstuff, nuclear radiation and genetic manipulation. Greens foster the illusion that if the planet were farmed organically all would be well.
With more than six billion mouths to feed, and an accumulation of greenhouse gases from our heavy industrial past and present, there is no returning to the romantic illusion of a pre-industrial Earth. Renewable energy and sustainable development are noble concepts for a time of environmental peace but inappropriate when we have made the Earth our enemy; what we need is a well planned retreat and preparations for the damage that soon may come.
Renewable energy might be a good idea in the long term, and is a showy way for politicians to prove that they are doing something, but it is already too late to expect it to play a significant role; global warming is already happening and is likely to intensify. To supplement the feeble energy supplies from renewables by lashings of natural gas is a risky option, particularly for Britain. The European encouragement of subsidised renewable energy might be justified were there no alternative tried and tested energy source - but there is: clean and safe nuclear energy. The objections to it are unscientific and perverse, but the green lobbies have preached against it until some European governments have been forced to act against the public good and allow it to be phased out.
In January, a symposium was held in Cambridge to discuss other ways to counteract global warming. The delegates presented a set of unusual remedies. These included space-mounted sunshades, a method for increasing cloudiness over the oceans, and the removal of carbon dioxide from smoke stacks or even from the air. It was encouraging to hear what was feasible but unfortunately, none was free of disadvantages or available now.
Moreover, the economist Shimon Awerbuch reminded us that the magical appearance of a clean, safe and economic source of energy would do little to stop the burning of fossil fuels, such is the human tendency to over-consume. Indeed, the spread of wind turbines in Germany has been accompanied by an increase in coal combustion, the dirtiest of all fuels. The earth system, Gaia, functions because within it are powerful restraints to growth, as we will discover. We have to make our own restraints if we are to avoid those the Earth will apply. Perhaps the unreasoning fear of nuclear energy at least implies some built-in restraint.
So what will happen and what should we do? There are three main alternatives. The first is laissez faire: continue to enjoy a warmer 21st century, and make cosmetic attempts to hide global warming. I suspect that this is what will happen in much of the world. Second is the deep green way: eat nothing but organic food, use nothing but renewable energy and raw materials. These policies might restore the Earth to health but at the cost of a massive reduction in the numbers of people and possibly the loss of some civilisations. There may be a third, less unpleasant, way: the high-tech road. It would require us to take global change seriously and lessen the footprint of humans on the Earth. First, and most important, it would mean no more natural habitat destruction. To attempt to farm the whole Earth to feed people makes us like sailors who burned the timbers and rigging of their ship to keep warm. Then we must embrace science and engineering; we need their skills and inventions to lessen our impact on the Earth. If more food comes from less land by genetic engineering then use it; better still, if food can be synthesised by the chemical and biochemical industries from carbon dioxide, water and nitrogen, then let's make it and give Earth a rest. We need a portfolio of energy sources, with nuclear playing a big part, at least until fusion power is an option, and we must stop fretting over the minute risks of cancer from chemicals or radiation. In Britain, one quarter of us will die of cancer anyway, mainly because we breathe air laden with that pervasive carcinogen, oxygen. If we fail to concentrate our minds on the real danger - global warming - we may die sooner, as did more than 20,000 unfortunates from overheating in Europe last summer.
The Kyoto protocol and the government white paper on energy use are small changes in the right direction but insufficient to alter the course of events and inadequate for stirring the altruism needed to curb emissions and our pressures on the land. My hope lies in that powerful force that takes over our lives when we sense that our tribe or nation is threatened from outside. In wartime we accept without question the severest of rationing and will readily offer our lives. Perhaps when the catastrophes of the intensifying greenhouse effect become frequent enough we will pull together as a global unit with the self-restraint to stop burning fossil fuel and abusing the natural world.
