BOOK REVIEW : A Biologist’s Spirited Defense of Science, Reason : THE UNNATURAL NATURE OF SCIENCE: Why Science Does Not Make (Common) Sense <i> by Lewis </i> W<i> olpert</i> Harvard University Press; $19.95, 191 pages

If Shakespeare had never been born, we would not have “Hamlet,” “Macbeth” or “The Merchant of Venice.” No one else would have written them.

But if Isaac Newton had never been born, we would still have the law of gravitation. Sooner or later, we believe, someone else would have discovered it.

These statements cannot be proved. Shakespeare and Newton were born, and we have no Shakespeareless and Newtonless world to compare with our own to see whether “Hamlet” was nonetheless being performed and gravity was unknown.

But the idea that artists create something unique while scientists discover laws that are already there is deeply embedded in our collective notion of reality.

This idea has come under powerful attack in the post-modernist age, where the “social construction of reality” is the rallying cry of those who claim that readers are more important than authors, that reality is malleable and that scientists, like artists, create the world more than discover it.

For example, some feminist scholars have written that modern science embodies a male, sexist reality in which forces “act on” objects, DNA is a “master molecule” and evolution is driven by a “struggle” to survive. A bias-free world, they say, might require redefining objectivity, rationality and the scientific method.

Into this argument steps Lewis Wolpert, a biologist at University College, London, who offers a spirited defense of traditional science, objectivity and reason. The world and its laws are independent of us, and scientists try to figure out those laws, which are timeless, universal and independent of human wishes. Scientific truth is public, testable and verifiable. In assessing a scientific statement, the only thing that matters is its correspondence with reality and its ability to predict the results of experiments.

“Science always relates to the outside world, and its success depends on how well its theories correspond with reality,” Wolpert writes on Page 2 of “The Unnatural Nature of Science,” a series of essays that uncompromisingly defends science as fully entitled to the special and privileged position that it enjoys. “Science provides the best way of understanding the world,” he says.

Wolpert is especially withering in his response to the relativists, philosophers of science, sociologists of science and Kuhnians (they of the “paradigm shifts”), who, in his view, create conundrums where there are none.

He probably speaks for all working scientists when he asserts: “My own position, philosophically, is that of a common-sense realist: I believe there is an external world which I share with others and which can be studied.”

He acknowledges that “authority, fashion, conservatism and personal prestige play important roles” in science. “But it is misleading to think, as some have claimed, that science is really nothing but rhetoric, persuasion and the pursuit of power.”

If a theory “does not conform with the evidence, if it is not internally consistent, it does not provide an adequate explanation, the authority and all the other social factors count for nothing: It will fail.”

To the relativists and post-modernists, Wolpert issues a simple and elegant challenge: What alternate theories do you have to explain the data? Is there a physics that is not based on a set of basic forces? Is a biology possible that is not based on cells and DNA? Is there a chemistry that does not include the periodic table?

There is much more to this wonderful book. Wolpert explains the difference between science and technology. Science is about generalization and abstraction. In itself, it is useless. Technology, on the other hand, produces usable objects.

Many civilizations had technologies, some of them, like the Chinese, quite advanced. But only the Greeks sought understanding. As a result, we trace science to them. No matter that almost all of the Greeks got the wrong answers. They asked the right questions.

Amid all of this fanfare for science and the scientific method, Wolpert’s prose is measured and thoughtful. He acknowledges the sources and strengths of other views, and he makes no claim that science can know everything. In fact, he makes clear that it can’t.

Moral and political problems are outside its purview, as are justice, happiness, love and ultimate values. These matters are in principle beyond the range of science.

Furthermore, some systems, such as human behavior and society as a whole, are so complex that “knowledge in these fields is barely at the stage of a primitive science.” We may some day be able to predict the stock market, but that day is neither foreseeable nor imaginable. So much for the social sciences.

In an age when fundamental ideas about the nature of truth are assailed, when scientists are derided as madmen who threatened the world with nuclear weapons and genetic engineering, it is a pleasure to read a clear, level-headed and persuasive defense of the scientific enterprise. We are better off with knowledge than without it.