Nature abhors a vacuum. Gravitational force is inversely proportional to the square of the distance between two objects. Over the course of evolution, each species develops larger body sizes. If something can go wrong, it will.
Such are some of nature's laws as handed down by Aristotle, Newton, Edward Cope and Murphy. And regardless of their varying accuracy (and seriousness), it takes an enormous amount of daring to posit them in the first place. Think of it: asserting that what you observe here and now is true for all times and places, that a pattern you perceive is not just a coincidence but reveals a deep principle about how the world is ordered.
If you say, for example, that whenever you have tried to create a vacuum, matter has rushed in to fill it, you are making an observation. But say that ''nature abhors a vacuum'' and you are asserting something about the essence of things. Similarly, when Newton discovered his law of gravitation, he was not simply accounting for his observations. It has been shown that his crude instruments and approximate measurements could never have justified the precise and elegant conclusions. That is the power of natural law: the evidence does not make the law plausible; the law makes the evidence plausible.
But what kind of natural laws can now be so confidently formulated, disclosing a hidden order and forever bearing their creator's names? We no longer even hold Newton's laws sacred; 20th-century physics turned them into approximations. Cope, the 19th-century paleontologist, created his law about growing species size based on dinosaurs; the idea has now become somewhat quaint. Someday even an heir to Capt. Edward Aloysius Murphy might have to modify the law he based on his experience about things going awry in the United States Air Force in the 1940's.
So now, into the breach comes John Brockman, the literary agent and gadfly, whose online scientific salon, Edge.org, has become one of the most interesting stopping places on the Web. He begins every year by posing a question to his distinguished roster of authors and invited guests. Last year he asked what sort of counsel each would offer George W. Bush as the nation's top science adviser. This time the question is ''What's your law?''