Quest and test - seeing the world with a scientist's eye

WHAT we call science started in Greece five centuries before Christ and got its second wind in Europe around AD 1600. Thereafter, it accelerated fairly smoothly into today's runaway expansion of knowledge. Nothing quite like it has happened independently anywhere else in the world. There were great technical achievements, especially in China, but they didn't converge. All advanced science now derives from or has been grafted onto the Western root. Why did it happen this way? That is a complicated question, to which we don't know the complete answer. Climate? Language? Religious freedom? The existence of a leisure class? What is clear is that science emerged naturally from other things people were doing - it wasn't, at first, something special or different.

It seems characteristic of human beings to be curious and to make up stories to account for things. For example, all cultures have been curious about the origin of the universe and ancestry of human beings, and have invented stories about gods, totem animals, cosmic births, floods, or whatever to satisfy this curiosity. The very early scientists were also philosophers (sometimes called ``nature philosophers'') and had the good sense, if it can be called that, to ask slightly different questions: What are things made of? Why do they behave as they do?

Even these questions would not have led to science if it had not been for one other thing - also a philosophical contribution. Stories about the creation of the world, the proper organization of society, and so on, tended to be told authoritatively: People learned them but did not challenge their authority, or if they did were likely to be treated severely, since the people who told the stories often had kingly or priestly power. But the stories of the nature philosophers were challenged - by other philosophers who made up different stories, and pointed out things that were contradictory or implausible.

Science grew and still grows by this process - inventing an account of something and criticizing that account. A scientific account, worked out in suitable detail and covering a number of related things or events, is called a theory (the word means a way of looking). In the natural sciences, one kind of criticism consists of confronting the theory with observational evidence: If the evidence doesn't fit, the theory must be abandoned and a new one offered, until a theory is found that survives the criticism.

What we know as science is the accumulation, from all sources and times, of tested theories of this sort. As people have communicated to one another the diverse results of their observations and experiments (an experiment is a contrived observation, making something happen when and where we can watch it), the language in which they couch their theories has become standardized. The tendency has been to gravitate toward Western languages, because most of the development of science took place in the West. Other contributions show up, though: Much of the terminology of mathematics and chemistry is of Arabic origin.

But science itself is not Western, or Eastern, or even regional. It deals with a world that is available to all: Things grow, fall, break, and burn in the same way everywhere; weather, the earth, the human body, are not culturally relative but of similar structure the world over. If different formulations of the same knowledge come from different cultural sources, they will, if it is scientific knowledge, prove to be equivalent.

Western thinkers have sometimes been unwilling to work on these equivalences, believing that eventually the world will be seen their way; but this, while perhaps somewhat arrogant, doesn't invalidate any tested results. Also, some scientists presume that what they know is all there is - to the detriment of beauty, feeling, or mystery. That is their loss. But again it doesn't invalidate scientific results. It is good to cultivate humanity in all its aspects, but it would be a disaster if science, because it doesn't cover all those aspects, were undermined.

But science is not the final word, even in its own domain. Scientific theories are always subject to correction - that's part of what it means for them to be scientific. Students of science are not always taught this lesson, and it is likely to be misunderstood. People sometimes think that if scientists are modest about their claims, they don't have confidence in them. ``It's just a theory'' is a way of dismissing results. But theories are all we have (billing them as revelations doesn't alter the case). If I have to admit my tested knowledge isn't final, that doesn't mean I ought to believe someone else's untested theory.

Perhaps the most valuable thing science has to teach us is how to judge when claims to truth are worthy to be believed and when they are not. It is important to learn scientific results; also to understand what things are made of, how they hang together, and how they work. (It is astonishing how illiterate many people are content to be about the world they live in.) But it is even more important to understand what knowledge is, how it is acquired, and to what extent it is to be trusted.

Only such an understanding will protect free and autonomous individuals from deception and exploitation - only if we have it can we be sure of being free and autonomous. Learning about science is the best way of acquiring it, and should be one of the cornerstones of the educational process.

Peter Caw is a professor of philosophy at George Washington University, Washington, D.C.