Description
Science is the search for the truth,» wrote chemist Linus Pauling, winner of two Nobel prizes. Bruce Alberts, current president of the U. S. National Academy of Sciences, agrees. «Science and lies cannot coexist,» said Alberts in May 2000, quoting Israeli statesman Shimon Peres. «You don’t have a scientific lie, and you cannot lie scientifically. Science is basically the search of truth.»
For most people, the opposite of science is myth. A myth is a story that may fulfill a subjective need, or reveal something profound about the human psyche, but as commonly used it is not an account of objective reality. «Most scientists wince,» writes former Science editor Roger Lewin, «when the word ‘myth’ is attached to what they see as a pursuit of the truth.» Of course, science has mythical elements, because all human enterprises do. But scientists are right to wince when their pronouncements are called myths, because their goal as scientists is to minimize subjective storytelling and maximize objective truth.
Truth-seeking is not only noble, but also enormously useful. By providing us with the closest thing we have to a true understanding of the natural world, science enables us to live safer, healthier and more productive lives. If science weren’t the search for truth, our bridges wouldn’t support the weight we put on them, our lives wouldn’t be as long as they are, and modern technological civilization wouldn’t exist. Storytelling is a valuable enterprise, too. Without stories, we would have no culture. But we do not call on storytellers to build bridges or perform surgery. For such tasks, we prefer people who have disciplined themselves to understand the realities of steel or flesh.
The discipline of science
How do scientists discipline themselves to understand the natural world? Philosophers of science have answered this question in a variety of ways, but one thing is clear: Any theory that purports to be scientific must somehow, at some point, be compared with observations or experiments. According to a 1998 booklet on science teaching issued by the National Academy of Sciences, «it is the nature of science to test and
retest explanations against the natural world.»
Theories that survive repeated testing may be tentatively regarded as true statements about the world. But if there is persistent conflict between theory and evidence, the former must yield to the latter. As seventeenth-century philosopher of science Francis Bacon put it, we must obey Nature in order to command her. When science fails to obey nature, bridges collapse and patients die on the operating table.
Testing theories against the evidence never ends. The National Academy’s booklet correctly states that «all scientific knowledge is, in principle, subject to change as new evidence becomes available.» It doesn’t matter how long a theory has been held, or how many scientists currently believe it. If contradictory evidence turns up, the theory must be reevaluated or even abandoned.
Otherwise it is not science, but myth. To ensure that theories are tested objectively and do not become subjective myths, the testing must be public rather than private. «This process of public scrutiny,» according to the National Academy’s booklet, «is an essential part of science. It works to eliminate individual bias and subjectivity, because others must also be able to determine whether a proposed explanation is consistent with the available evidence
Contents
Preface xi
Chapter 1 Introduction
Chapter 2 The Miller-Urey Experiment
Chapter 3 Darwin’s Tree of Life
Chapter 4 Homology in Vertebrate Limbs
Chapter 5 Haeckel’s Embryos
Chapter 6 Archaeopteryx: The Missing Link
Chapter 7 Peppered Moths
Chapter 8 Darwin’s Finches
Chapter 9 Four-Winged Fruit Flies
Chapter 10 Fossil Horses and Directed Evolution
Chapter 11 From Ape to Human: The Ultimate Icon
Chapter 12 Science or Myth?
Appendix I An Evaluation of Ten Recent
Biology Textbooks
Appendix II Suggested Warning Labels for
Biology Textbooks
Research Notes