JAMES LOVELOCK sees the most urgent and challenging frontier during the next century all around us. Dr. Lovelock, father of the now-famous Gaia theory, which considers the whole planet as a sort of "superorganism," regulating conditions appropriate for life, says he believes that Earth may be showing signs of disease - from greenhouse fevers to acid-rain indigestion and ozone spots. He argues that it's time for some planetary medicine and it's not enough to rely on the sciences to provide it.
Lovelock, a distinguished scientist who started out at the National Institute for Medical Research in London during World War II, abandoned "career science" in 1964 and has worked independently since then, presently from his home and laboratory in southwest England. He worries that science is losing sight of problems we face.
"The younger, expert scientists take a narrower reductionist, 'bottom-up' view, studying details and processes within their fields. They recognize that life on Earth affects its environment as well as adapting to it, but they have lost the great vision that saw life and its material environment as a single system."
Lovelock traces the great vision back to the 17th-century geologist James Hutton, who compared the Earth's water cycle to William Harvey's then newly described circulation of the blood. He says Gaia builds on this vision and is vital for future environmental strategies.
"The idea of Gaia came quite suddenly, like a flash of enlightenment," says Lovelock. He was working at the National Aeronautics and Space Administration (NASA) Jet Propulsion Laboratory in Pasadena, Calif., in the 1960s on methods for remote detection of life on other planets. He and a colleague suggested that the atmosphere of a dead planet would be close to equilibrium, that is, all possible chemical reactions would have taken place. A planet bearing life, which uses the atmosphere as a source of mate rials and a depository for waste products, would have a very different atmosphere.
"With this in mind, we were considering what was known of Mars and Venus. We discovered both had atmospheres close to equilibrium, like exhaust gases. To confirm the prediction, we looked at the Earth's atmosphere and found to our delight a state of deep disequilibrium, with gases that react together, such as oxygen and methane, coexisiting. The atmosphere is like a dilute fuel mixture," he says.
"At that moment I glimpsed Gaia. The Earth's atmosphere was an extraordinary and unstable mixture of gases, yet it was constant in composition over long periods of time. Could it be that life not only made the atmosphere but also regulated it?"
Lovelock was involved in the subsequent NASA Viking mission to Mars, but his findings failed to influence the projects. "The mission was squandered by idiot big scientists convinced there was life on Mars, when it was quite obvious there wasn't. They dedicated their whole mission to that idea rather than learning as much as possible about the planet from the precious opportunity of two spacecraft sent there."
Since the idea of Gaia, first published in the Proceedings of the American Astronautical Association in 1968 but named only some years later at the suggestion of Lovelock's neighbor novelist William Golding, its influence has grown enormously.
Many scientists dismiss it: The planet cannot breed, therefore it cannot be alive, is one of the criticisms of hard-line biologists. But for others it has prompted experiments, and beyond science it has achieved something of a spiritual status for some people. Three years ago, Gaia was the topic of a US science conference for the first time, and the distinguished journal Nature said that whether the theory was correct may matter less "than that it is stimulating".
But isn't growing awareness of environmental problems a mark that science has recognized the importance at least of planetary diagnosis, if not medicine? Both NASA and the European Space Agency have begun a series of environment-monitoring satellites.
"They have enormous potential that they almost certainly won't realize," Lovelock says. "The best example is the appalling scandal of the space mission to find the ozone hole. Instruments found the hole, but scientists on the ground were so sure it couldn't be any such thing, because the models didn't predict it, that they programmed the instruments to ignore it. It took two old-fashioned British scientists with a simple hand-held instrument looking up to find it. I think there is a great moral in that t ale. It's a wrong way to do science with that gigantic big stuff.
"Vast amounts of money are spent on ozone research," he says. "But we know what is happening and we know the cure - a bit a dieting. We need a bit of monitoring, but we do not need to spend enormous amount of money on it."
He sees in these examples the frailty of science as a human institution, that it is slow and its record in handling immediate environmental problems is far from good. "It concentrates almost excessively on minor matters that happen to worry the public, such as carcinogens in the environment, or on phenomena in the stratosphere that are intensely interesting to scientists, but that are easily managed environmental problems requiring only common sense for their solution."
In Lovelock's common-sense, physiological view of the planet's predicament, one problem that needs immediate attention stands out above all the others.
The most important threat is the destruction of natural habitats by farming on a huge scale, particularly the tropical forests, he says. "It transcends all other threats enormously. A system of dedicated satellites, not necessarily expensive ones, keeping a constantly updated map of the world, has enormous potential.
"There are a billion people in the tropics, and at the present rate of destruction all forests will be gone by 2010. Past record suggests it will all go to scrub or desert. Who will feed these people? How will we cope with the refugees? Its all just around the corner and transcends the ozone problem by an enormous amount."
Climate change is second to habitat destruction but the rest of the problems are way down below, Lovelock says. Extending his physiological analogy, he diagnoses a key planetary malaise as an excess of people. Conditions for life on Earth have flipped suddenly from one state to another at times in the past, and this, he warns, may occur again. Life and Gaia would go on, but we might no longer be part of it.