WHAT IS SCIENCE?*

We begin our study of biology by asking: What is science? How did it originate? How did it develop?

You may be surprised to learn that the origin of science lies in the supernatural. Several thousand years ago people lacked the knowledge necessary to explain the universe and its workings in "scientific" terms. To early humans, the forces of nature were both powerful and unexplainable. Yet their origin and control must exist somewhere, perhaps in some being - or beings - more powerful than man himself. Undoubtedly, such reasoning led to the establishment of primitive religions and the belief that the world and all happenings in it were under the controlling influence of spirits and gods.

Many primitive cultures believed that events beneficial to human welfare were controlled by benevolent spirits. Other spirits, such as those bringing sickness and death, were evil and malicious. Still others appeared exceedingly unpredictable, friendly one moment and hostile the next. The impulsive character of these beings explained why a gentle rain might eventually develop into a disastrous flood. Such is the origin of myths.

Early humans never held out hope of understanding such gods. These people did attempt, however, to appease and influence them through creation of various rites and rituals. For instance, the earliest farmers believed that the phenomenon of rainfall was similar to a sexual act; sex and rainfall were both associated with fertilization, reproduction and growth. Indeed, many early cultures believed that sex and rainfall were under the control of identical or similar gods. Farmers thereby could not only "explain" the phenomenon of rainfall but also had "discovered" the god with the appropriate rites. Thus, in many cultures, attempts to bring rain were accompanied by rituals involving intense sexual activity.

On many occasions the ritual appeared to succeed. Rains often did come a few days following the ritual. such results reinforced the idea that sex and rainfall were indeed related and that unseen spirits could be influenced. Rituals, however, did not produce desired results in all cases. In time, more perceptive individuals realized that rituals played no role in controlling the forces of nature. This was a momentous discovery and a scientific one.

The first to make and record this discovery were the ancient Greek philosophers. Most of these men became convinced that the universe was a great machine governed by inflexible laws. They began the exciting intellectual exercise of attempting to discover the nature of those laws. They established an orderly system of logic essential to anyone trying to determine underlying laws of nature from observed data.

The rules of this system, or philosophia ("philosophy") as it came to be called, were threefold: Observation, categorizing and deduction. First, the "philosopher" must collect observations about some aspect of nature. For example, a stone sinks in water, wood floats, an iron bar sinks, a drop of salad oil floats, a drop of mercury sinks. Next, the observations must be organized in an ordered fashion. All objects that sink in water are listed in a column; all objects

that float are placed in an adjacent column. Finally, an underlying principle of nature is obtained by examining relationships between the ordered items. Thus, heavy objects sink in water and light objects float.

Such sets of "philosophical rules" constitute what later came to be called inductive and deductive logic. The significance of the establishment of these contrasting kinds of logic cannot be overstated. As you will find later in this paper, inductive logic is used in formulating most scientific theories. Deductive logic provides the basis for the design of virtually all experiments in modern science.

The second major Greek contribution to what was to become science was the philosophy of mechanism, which officially marks the initial divergence of "science" from its supernatural heritage. In the mechanistic view of nature, the universe is governed by a set of natural laws, namely, the laws of physics and chemistry. The mechanistic philosophy holds that if all physical and chemical events in the universe can be accounted for, no other events will remain. Therefore, life, too, must be a result of physical and chemical processes only, and the course of life must be determined automatically by the physical and chemical occurrences within living matter.

This mechanistic philosophy stands in opposition to vitalism, which maintains that the universe, and particularly its living components, are controlled by supernatural powers. Such powers are held to guide the behavior of atoms, planets, stars, living things and indeed all components of the universe. Most religious philosophies are inherently vitalistic.

Clearly, these differences between vitalism and mechanism point up a conceptual conflict between religion and science. However, this conflict is not necessarily irreconcilable. To bridge the conceptual gap, one might ask how the natural laws of the universe came into being to begin with. A possible answer is that they were created by God. On this view, it could be argued that the universe ran vitalistically up to the time that natural laws were created and mechanistically thereafter. The mechanist would then have to admit the existence of a supernatural Creator at the beginning of time (even though he has no scientific basis for either affirming or denying this; mechanism cannot, by definition, tell anything about a time at which natural laws might not have been in operation). Correspondingly, the vitalist would have to admit that, so long as the natural laws continue to operate without change, supernatural control would not be demonstrable.

Thus it is necessarily illogical to accept both scientific and religious philosophies at the same time. However, it is decidedly illogical to try to use religious ideas as explanations of scientific problems or scientific ideas as explanations of religious problems.

Yet many people, some scientists included, still find it exceedingly difficult to keep vitalism out of science. Biological events, undoubtedly the most complex of all known events in the universe, have been particularly subject to attempts at vitalistic interpretation.

Even a casual observer must be impressed by the apparent non-randomness of natural

events. Every part of nature seems to follow a plan, and there is a definite directedness to any given process. In living processes, for example, developing eggs behave as if they knew exactly what the plan of the adult is to be. A chicken soon produces two wings and two legs, as if it knew that these appendages were to be part of the adult. All known natural processes, living or otherwise, similarly start at given beginnings and proceed to particular end-points. This observation poses a philosophical problem: How is a starting condition directed toward a specific terminal condition? How does a starting point appear to "know" what the endpoint is to be?

Such questions have to do with a detailed aspect of the more general problem of the controlling forces of the universe. We should expect, therefore, that two sets of answers would be available, one vitalistic and the other mechanistic. This is the case. According to vitalistic doctrines, natural events appear to be planned because they actually are planned. A supernatural "divine plan" is held to fix the fate of every part of the universe, and all events in nature, past, present, and future, are programmed in this plan. All nature is therefore directed toward a preordained goal, the fulfillment of the divine plan. As a consequence, nothing happens by chance but everything happens on purpose.

Being a vitalistic, experimentally untestable concept, the notion of purpose in natural events has no place in science. Does the universe exist for a purpose? Do people live for a purpose? Science is not designed to tackle such questions. Moreover, if you already hold certain beliefs in these areas, you cannot expect science either to prove or to disprove them for you.

Yet many arguments have been attempted to show purpose from science. For example, it has been maintained by some that the whole purpose of the evolution of living things was to produce people - the predetermined goal from the very beginning. This conceit implied not only that people are the finest product of creation but also that nothing could ever come after human beings, for we are supposed to be the last word in living magnificence. As a matter of record, people are sometimes plagued by parasites that cannot live anywhere except inside human beings. And it is clear that you cannot have a person-requiring parasite before you have a person.

The form of argumentation that has recourse to purposes and supernatural planning is generally called teleology. In one system of teleology, the preordained plan resides within objects themselves. According to this view, a starting condition of an event proceeds toward a particular end condition because the starting object has built into its supernatural foreknowledge of the end condition. For example, an egg develops toward the goal of the adult because the egg is endowed with information about the precise nature of the adult state. Clearly, this and all other forms of teleology "explain" an end state by simply asserting it to be already mapped out at the beginning. And in thereby putting the future in the past, the effect before the cause, teleology negates time.

The scientifically useful alternative to teleology is Causalism, a form of thought based on mechanistic philosophy. Causalism denies foreknowledge of terminal states, preordination, purposes, goals and fixed fates. It holds instead that natural events take place step-wise, each one conditioned by, and dependent on, earlier ones. Events occur only as previous events permit them to occur, not as preordained goals or purposes make them occur. End states are consequences, not foregone conclusions, of beginning states. A headless earthworm regenerates a new head because conditions in the headless worm are such that only a head - one head - can develop. It becomes the task of the biologist to find out what these conditions are and to see if, by changing the condition, two heads or another tail could be produced. Because scientists actually can obtain different end states by changing the conditions of initial states, the idea of predetermined goals loses all validity in scientific thought.

Care must therefore by taken in scientific endeavors not to fall unwittingly into the teleological trap. Consider often-heard statements such as: "The purpose of the heart is to pump blood;" "the ancestors of birds evolved wings so that they could fly;" "eggs have yolk in order to provide food for development." The last statement, for example, implies that eggs can "foresee" that food will be required in development and they, therefore, store up some. In effect, eggs are given human mentality. Teleologists are always anthropocentric, that is, they imply that the natural events they discuss are governed by minds like theirs. In making biological statements some of the theological implications can be avoided by replacing every "purpose" with "function," every "so that" or "in order to" with "and."

Clearly then, science in its present state of development must operate within carefully specified, self-imposed limits. The basic philosophic attitude must be mechanistic and causalistic, and we note that the results obtained through science are inherently without truth, without value and without purpose. But it is precisely because science is limited in this fashion that it advances. Truth is as subjective as ever, values change with time and place, and purposes basically express little more than our desire to make the universe behave accordingly to our own very primitive understanding. It has therefore proved difficult to build a knowledge of nature on the shifting foundation of values and truth or on the dogma of purpose. What little of nature we really know and are likely to know in the foreseeable future stands on the bedrock of science.

Although many roots of modern science can be traced to the early Greeks, their "natural philosophy" was marred by one highly significant defect - they regarded experimental testing of their conclusions as unnecessary. To a Greek philosopher, arrival at "absolute truth" through deductive reasoning was the height of intellectual excellence. It was absurd and degrading to suggest that conclusions resulting from such a perfect system of logic required confirmation through direct testing.

Indeed, many of their original conclusions about the operations of the universe are consistent with those derived through more recent experimental testing. There is no doubt that Aristotle and many of his colleagues were extraordinarily gifted in their use of deductive logic. But use of deductive logic is not infallible. As you will note presently, some of Aristotle’s absolute truths later were found to be neither absolute nor valid.

Natural philosophy became less popular during the rise of the Roman Empire, and following the collapse of Roman rule and the rise of Christianity, moral philosophy, based on vitalistic arguments, was the chief intellectual pursuit. Natural philosophy was virtually forgotten until the beginning of the Renaissance in the fourteenth century.

Primarily it was Galileo, who delivered the death blow to the ancient Greek practice of establishing conclusions without experimental evidence. For example, Galileo provided a direct test of Aristotle’s idea that objects would fall at a rate directly proportional to their weight, an "absolute truth" that had gone unchallenged for nearly 2000 years. Galileo is reported to have climbed to the top of the leaning tower of Pisa and dropped two balls of unequal weight. Aristotelian science died the instant the two balls struck the ground simultaneously.

In view of the significance of this result, it is ironic that Galileo probably never actually performed the experiment as reported. It was so typical of his dramatic exploits, however, that this legend has survived for centuries. Undoubtedly, Galileo conducted equally valid experiments disproving Aristotle’s theory by rolling balls down inclined planes. From Galileo’s day to the present time, everything that is properly called science has been based on experiments designed in accordance with scientific methods.

Modern scientists often solve problems and make discoveries through use of a sequence of interrelated steps outlined below. Such steps sometimes are erroneously termed the scientific method, but it soon will become apparent that scientists do not always follow the order of steps listed, nor are all of these steps always included in the solution of every problem. There is no single, uniform, or absolute scientific method, and no research scientist follows a formalized ritual in performing experiments. Indeed, there is wide disagreement among scientists about the nature of scientific methodology. Nevertheless, observations of natural phenomena often set in motion a series of subsequent mental and physical activities among scientists that eventually lead to the uncovering of new facts and the refining of old principles.

Observation immediately puts a boundary around the scientific domain; something that cannot be observed cannot be investigated by science.

Everybody observes - with eyes, ears, touch and all other senses - and, therefore, everyone has the potential to be a scientist. It is important to observe correctly, however. Unsuspected bias can seriously impede good observation. People often see only what they want to see or what they think they ought to see. It is extremely hard to rid oneself of such unconscious prejudice and to see just what is actually there, no more and no less. Past experience, "common knowledge," and often teachers can be subtle obstacles to correct observation, and even experienced scientists may not always avoid them. That is why a scientific observation is not fully accepted until several scientists have repeated it independently and have reported the same thing. That is also a major reason why one-time, unrepeatable events generally cannot be investigated scientifically.

After an observation has been made, a second usual step of scientific procedure is to define a problem; one asks a question about the observation. Again, most people already possess the basic skills to define problems. Having a curious and inquisitive nature is really the most important element for this step. If you have wondered why leaves turn color in fall, or why sap flows in trees, or how homing pigeons navigate, you are implicitly asking a question about a natural process.

Once a proper question has been asked, the common third step of scientific methodology usually involves the seemingly quite unscientific procedure of guessing what the answer to the question might conceivably be. Scientists refer to this as postulating a hypothesis. To have scientific value, hypotheses must be both logical and testable. It must be possible to evaluate the validity of a hypothesis; otherwise it is impossible to determine whether a proposed explanation is right or wrong.

Scientists generally use inductive logic in the formulation of hypotheses. Inductive logic involves coming to a general premise on the basis of many individual observations. For example, a person might notice that water in a nearby stream flows downhill. The person might then observe that water in sink, in a river, and in a drainpipe also flows downhill. From these several observations, the person might use inductive logic to conclude that water always flows downhill. Knowingly or unknowingly, this person has established a testable hypothesis: "Water always flows downhill."

A further example will illustrate how inductive reasoning can be used to establish hypotheses that relate to biological processes. Consider the phenomenon of seasonal changes in coat coloration of snowshoe hares, animals found in Canada and the northern United States. The fur of these animals appear white in winter and brown in summer. This trait provides considerable survival potential, for their coats blend with the background coloration of the environment at any season. This observation has been made repeatedly by trappers, hunters, and others living in the northern latitudes, and many of these people undoubtedly have marveled as snowshoe hares change coat color in concert with the changing seasons.

An obvious question about this phenomenon arises in the mind of an inquisitive observer: What is responsible for the seasonal change in coat color among snowshoe hares? There are several possible answers to this question. We might note that steadily decreasing temperatures in fall and increasing temperatures in spring are responsible for many environmental changes. Ice forms as winter approaches, and it melts in spring. The ground freezes in winter, thaws in spring. Using inductive reasoning, we might hypothesize that seasonal changes in temperature are also responsible for observed changes in the coat color in snowshoe hares.

The tentative conclusions about the flow of water and coat-coloration changes in snowshoe hares are examples of the two kinds of hypotheses usually formulated by scientists. The first, called generalizing hypotheses, simply summarize a group of specific observations and permit logical, summary conclusions to be tested. The conclusion "water always flows downhill" is a generalizing hypothesis. The second kind of hypothesis, explanatory hypotheses, generally have greater scientific importance. They do more than generalize from a group of similar observations. Explanatory hypotheses are tentative explanations of causes of natural phenomena. The suggestion that "changes in temperature trigger seasonal coat-color changes in snowshoe hares" can be categorized as an explanatory hypothesis.

As scientists, we have no way of knowing whether our hypotheses are correct or incorrect. A given question can have thousands of logical answers but often only a single right one. Thus, chances are excellent that a random guess will be wrong. To distinguish between wrong hypotheses and right ones, we must establish tests of individual hypotheses. Testing hypotheses often is the most tedious part of science. Yet in science there is no other way. Science proceeds solely by postulating hypotheses. Testing hypotheses often is the most tedious part of science. Yet in science there is no other way. Science proceeds solely by postulating hypotheses and testing their predictions, and it is this quality which distinguishes science from most other disciplines.

There are two general ways of testing hypotheses. The first is by looking for naturally occurring observations that either support or invalidate a hypothesis. Many generalizing hypotheses lend themselves to such testing. For example, the hypothesis "water always flows downhill" can be tested simply by looking a large numbers of naturally flowing bodies of water. All bodies of water that flow downhill provide additional support for the hypothesis. However, bodies of water occasionally do flow uphill, as when incoming tides force water upstream in tributaries emptying into oceans along coastal shores. They hypothesis as stated is therefore false, disproved by a single contradictory observation.

Some hypotheses, explanatory ones in particular, often cannot be tested by naturally occurring observations. For these, observations must be generated by experimentation.

Guesses that are correct explainations of natural phenomena can be termed true hypotheses. The major principle underlying the experimentation step of scientific inquiry is that true hypotheses can never give rise to a prediction that can be proved false.

This principle can be illustrated through our hypothesis that temperature is the environmental factor responsible for triggering seasonal color changes in snowshoe hares. A testable prediction of this hypothesis can be obtained through deductive logic. This kind of reasoning proceeds from a general premise to specific conclusions that are based on the premise and therefore is the opposite of inductive logic (Table 1, p. 13). Sometimes called "if...then..." reasoning, deductive logic is used extensively by scientists to obtain predictions from hypotheses. For example: If temperature is the environmental factor responsible for triggering seasonal color changes of snowshoe hares, then hares kept at winter temperatures in spring and summer will retain their white coat and will not change to brown. The portion of the preceding sentence following the word "then" is a logical conclusion of the portion stated before the word "then." All that a scientist need do now is test the validity of the conclusion (prediction) to ascertain the validity of the accompanying hypothesis.

Usually, predictions from hypotheses can be obtained easily through application of the "if...then..." deductive format. Most scientists are so accustomed to deductive reasoning that formal construction of "if...then..." statements is unnecessary in setting up experiments. However, formal construction of "if...then..." statements is helpful in gaining an appreciation of how scientists design experiments.

Use the following procedure to accustom yourself to this format. First, write down a testable hypothesis. Place the word "if" before the hypothesis, and follow it with the word "then." Complete the now unfinished sentence with a logical conclusion. As a scientists, your next task would be to construct an experiment to provide a "yes" or "no" answer to your prediction.

Our hypothesis regarding coat-coloration changes in snowshoe hares can be used to illustrate this next step of scientific inquiry. Assume that an experimenter takes a white snowshoe hare from the field in December and places it in a refrigerated room where "winter" temperatures can be maintained indefinitely. The hare is retained in this room until late the following summer. Suppose the hare’s coat color remain white. Would this prove that change in temperature is the environmental factor responsible for triggering the seasonal color changes? Certainly not.

Temperature is only one of several environmental changes that could have accounted for the hare keeping its white coat. Perhaps some factor in the hare’s natural diet is responsible for changes in coat color. This factor may not have been present in the laboratory food after the hare was moved to the refrigerated room. Or perhaps the longer daylight hour in spring are responsible for triggering the coat-coloration changes. Lack of change might have been a result of illumination patterns in the refrigerated room that differed from those in nature.

What is clearly needed here is experimental control - for every snowshoe hare maintained in the refrigerated room, a precisely qual group must be maintained in another room where all environmental conditions are identical except for temperature. If the two groups respond differently, the responsible factor must be temperature because all other factors are identical for both groups.

Thus, every experiment requires at least two parallel test identical in all respects except one. One set of tests is the control series, to provide a standard of reference for assessing the results of the experimental series. Such procedures are often laborious, expensive, and time-consuming. In drug experiments on people, for example, up to 100,000 to 200,000 tests, half of them controls and a half of them experimentals, must sometimes be performed. And despite a most ingenious design and a most careful execution, the result may still not be a clear "yes" or "no." In a drug testing experiment, for example, it is virtually certain that some of the ill test subjects in the experiment, for example, t is virtually certain the some of the ill test subjects in the experimental group will not respond to the drug treatment, while some of the control subjects will bet better even without the drug.

The result of any experiment represents evidence, scientific evidence can be strong and convincing, or merely suggestive, or poor. With regard to snowshoe hares, the evidence is strong that temperature is not the main environmental factor responsible for triggering seasonal coat-color changes. Hares maintained at "winter" temperatures in greenhouse environments undergo a spring change to brown coats at the same time as hares maintained in the same greenhouse at outside temperatures. Evidence obtained through other experiments supports the hypothesis that seasonal change in day length is the environmental factor responsible for triggering coat-color changes. This hypothesis has been endorsed by most scientists because of the strength and consistency of the experimental evidence. It is incorrect to conclude, however, that the hypothesis has been "proved." No scientific evidence, regardless of strength, can ever prove the absolute validity of any hypothesis. This inability is inherent in the nature of scientific methodology.

Recall that science proceeds by testing predictions deduced from hypothesis and that true hypotheses can never give rise to false predictions. However, false hypotheses can give rise to predictions that will be supported by the results of valid experiments. This principle can be illustrated through another of Aristotle’s erroneous absolute truths. The Greek philosophers believed that the earth was the center of the universe and that the sun circled the earth daily. Apply deductive reasoning to this hypothesis to obtain a testable prediction: If the earth is the center of the universe, then the sun should rise on one horizon in the morning, move across the sky, and set on the opposite horizon. So it does. Thus, predictions that are verified by the results of experiments do not prove hypotheses. At best, we can only state that experimental evidence "supports" or "is consistent with" specific hypotheses. There is always room for more and better evidence or for new contradictory evidence or for better hypotheses.

Experimental evidence is the basis for the final step in scientific procedure, the formulation of a theory, a broadly based gypothesis supported by many tests that usually have been conducted over several years. Theories that withstand the test of thousands of individual experiments are sometimes called scientific laws. The law of gravity and the second law of thermodynamics are common examples.

Most theories, however, have brief life-spans. For example, consider the simple theory "Day length is the environmental factor responsible for triggering seasonal coat-coloration changes in all mammals that are white in winter and brown in summer." This theory requires immediate modification since the coat colors of many mammals are influenced by factors other than day length. Such exceptions to theories become new observations, which often lead to new hypotheses, new experiments, and new or revised theories.

As mentioned earlier, however, it is incorrect to conclude that scientists usually follow an ordered list of steps in solving problems. How testable hypotheses are formulated and experiments designed varies considerably from one scientist to another and from one situation to another. this is because hypothesis formation and experimental design are activities that are essentially creative, not prescribed.

To be sure, good scientists usually are expert at formulating generalizing and explanatory hypotheses. They often are quick to develop ways of testing hypotheses that are both reliable and effective. In addition, good scientists generally take immediate advantage of situations that provide unique opportunities for making new observations about natural processes, and they recognize that scientific inquiry is not restricted to bright, modern laboratories filled with complex and expensive equipment. But why some scientists are more perceptive than others is not well understood.

It should now be clear that scientists cannot be the cold, inhuman automatons they are so often pictured to be. Scientists are essentially artists who require a sensitivity of eye and of mind as great as that of any master painter, and an imagination and keen inventiveness as powerful as that of any master poet.

Because of the enormous impact of science on modern society, there exists a tendency among many people to regard science as potentially unlimited in its capacity to solve problems. Others look on science as an all-powerful force whose capacity to destroy and corrupt is infinite. Our examination of scientific methodology has revealed several limitations that nullify both of these views.

First, science cannot answer all categories of questions. Thus, questions that do not lead to testable hypotheses are outside the domain of science. How often have you heard that "science argues against the existence of God" or that "science is antireligious?" Such statements assume that science can prove or disprove the existence of God. Consider how science would attempt to answer this question. A hypothesis is needed. Suppose we "guess" that God does not exist. Being untested, this hypothesis might be right or wrong. Regardless of any prediction obtained through deductive logic, an experiment about God would require experimental control, that is, two situations, one with God and one without, but otherwise identical.

If our hypothesis is correct, God would not exist anywhere. Hence He would not be present in any test we might conduct. Yet for a controlled experiment, we would need a test in which God was present. On the other hand, if our hypothesis is wrong, He would exist everywhere and would be present in every control situation we might devise. Yet for a controlled experiment, we would need to construct a situation in which God was not present. Clearly, the quesiton of God’s existence is untestable scientifically.

Science is useless as a tool to discover or evaluate any truth that cannot be tested experimentally. Moreover, we have already learned that scientific truths are rarely absolute. Theories are being modified continually in the light of new evidence. Frustration awaits all who look to science for absolute truth.

Second, science cannot guarantee quick solutions to troublesome problems. No scientist, for example, can guarantee that the results of an experiment will support a hypothesis. Often there are hundreds of wrong hypotheses for every correct one, and experiments that prove hypotheses incorrect usually take as much time to carry out as those that provide supporting evidence. Proving hypotheses incorrect, however, usually does little to increase our ability to solve practical problems.

It is equally impossible for scientists to predict the potential usefulness of their experimental results. Many non-scientists fail to recognize this limitation and sometimes complain about their tax dollars being spent on research having no direct, practical "relevance." The frequently argue that most of their tax dollars should be spent on applied science, which concerns itself with immediate human needs; corresponding little should be expended on basic or pure science, which seeks to develop knowledge about the operation of the universe and its parts, without regard to practical application. Why support studies of coat-color changes in snowshoe hares or the behavior patterns of fish when a much more pressing concern is to find cures for cancer and other diseases?

Such arguments reflect two basic misconceptions about the interdependence between pure an applied science. One is the assumption that knowledge having direct human application derives exclusively from applied research. Very often the results of basic research prove this assumption false.

For example, much applied research has been carried out to discover an effective and safe shark repellent. such a chemical would have obvious practical value in ensuring the safety of swimmers in shark-inhabited waters. However, most chemicals that have been tested have proved ineffective or unreliable. Recently, an extremely potent shark repellent was found in the secretions of a small flouderlike fish inhabiting the Red Sea. This secretion apparently protects the fish from attacks by sharks and probably from other predators as well. The scientists who made this discovery were engaged in basic research and were not attempting to isolate a shark repellent. Their discovery was accidental and could not have been predicted in advance. Yet their findings could lead to the eventual development of a highly effective agent against sharks. The point is clear; if support is given exclusively to research dealing with "practical" problems, society will deprive itself of many unpredictable applications of knowledge derived from basic research.

The argument that applied science is "more important" than basic science contains a second and more serious flaw. Study of seasonal coat-color changes in snowshoe hares, for example, may not provide any information of immediate usefulness to human being. However, it does provide a small piece of information about the way living systems react to their environment. Coupled with countless other pieces of information, gathered through years of painstaking efforts, a more complete understanding of the general principles governing the operation of living systems - living human systems included - are bound to emerge. Entirely new and different application can then result from this more complete understanding, perhaps generating solutions to many different human problems. A scientific "breakthrough" will have been achieved many times in the past, almost invariably with diverse "practical" benefits for humanity.

Contrary to popular opinion, such breakthroughs do not develop suddenly. They almost always rest upon a bedrock of fundamental knowledge developed slowly through years of basic research. Discovery of the Salk vaccine against polio, for example, depended on a fundamental understanding of the nature and life cycle of viruses. Development of this understanding took years and hundreds of experiments.

The moral of this lesson is not that society must support all experiments of all scientists. As human beings, some scientists are more gifted and productive than others. Certain experimental approaches are more likely to succeed than others. But we must always recognize the interdependence of applied and basic science. Neither can exist without the other. Every basic scientist depends on equipment and techniques developed by applied science, and every applied scientist depends on ideas, insights, and knowledge generated by basic research. Starve either form of science and both will suffer. Failure to recognize this fundamental interdependence will frustrate all long-term attempts to speed application of science to human problems by increasing support of applied research at the expense of basic research.

Application of science to human needs is also slowed by the collaborative nature of the discipline. As applied and basic research are interdependent, so are scientists themselves interdependent. No experimental result is ever accepted by the scientific community at large unless and until is has been repeated by a second, independent scientist. This practice helps to ensure that the body of facts composing scientific knowledge is accurate and unbiased. In effect, the ability of science to solve problems quickly is sacrificed deliberately to ensure orderly, steady and reliable progress and to avoid the wastefulness and chaos that otherwise would result.

Finally, science is limited by its inability to make moral or value judgments. Scientific results by themselves do not contain any built-in values, and nowhere in scientific inquiry is there a value-revealing step. As a tool, like a hammer or a paint-brush, science is inherently neither good nor evil, responsible or irresponsible, powerful or impotent. Those who perceive such values or purposes in science are, in reality, merely viewing a reflection of human values and purposes. Thus, the science that produces weapons for destroying and killing and weapons for healing and creating cannot, of itself, determine whether such tools are good or bad. The decision in each case must rest on the moral opinions of people.

If human beings must determine the uses of science, how should such decisions be made? It might be possible, for example, to give scientists the exclusive right to make all decisions related to social applications of scientific theory. But most people, most scientists included, do not believe that such decisions should be left to any one segment of society. Scientists are no better suited to make decisions involving the justice or injustice of, say, abortion than lawyers, plumbers, or bricklayers. Science and technology have made the abortion of human fetuses relatively safe and practicable, but science does not and cannot establish moral and societal standards for the practice itself.

Nevertheless, some scientists argue that they have a special responsibility to influence public decisions that relate to uses of scientific knowledge. Such scientists believe that this responsibility grows out of their special training and their ability to perceive social implications of developing technologies before they are recognized by the general public. Others question the motivation of these often outspoken individuals and believe that scientists should merely present unbiased information and leave all final decisions concerning the uses of scientific knowledge to the public.

There are similar disagreements concerning the role of the lay citizen in science. some scientists insist that nonscientists should have little input into decisions relating to scientific experimentation. These scientists argue, for example, that issues relating to the dangers of specific experimental techniques are too complex for people who lack formal scientific training. Others reply that nonscientists can make rational policy judgements regarding scientific procedures and issues if they have an opportunity to hear articulate advocates present their case and respond to opposing arguments. Indeed, many who support an increased role for the nonscientist in decisions involving scientific matters favor creation of special adversary forums where significant questions of science and technology can be debated in front of panels of impartial judges. Such panels might issue judgments that pertain to disputed technical issues, and these opinions could then be used in the drafting of local, state or national laws.

Proposals for the establishment of such forums stem in part from the demands of increasing numbers of nonscientists who want greater participation in decisions involving the use of certain kinds of experimental procedures in research laboratories. Other lay citizens have witnessed the environmental and human devastation that can result from misuse of scientific knowledge and now wish a formal role in directing science toward more "responsible" goals.

Despite protestations by some and misinformed views of science by others, this recent trend toward a democratization" of science is likely to become more pronounced in the years to come. In the United States and many other countries, relationships between the discovery and use of scientific knowledge probably will be defined increasingly by "science courts," boards of review, legislative committees and city councils.

Although such "democratization" can do much to increase public respect and support of science, it cannot be accomplished unless scientists remain attentive to the views and fears of the lay citizen concerning the discovery and use of scientific knowledge, and scientists must do more to educate the public about the nature of science and specific scientific issues. For their part, nonscientists must obtain at least a rudimentary knowledge of scientific principles, understand the relationships between basic and applied science and be aware of both the potentials and limitations of science. Only then will scientists and nonscientists be able to work cooperatively and intelligently criticize, question and evaluate future applications of scientific theory.

Inductive Deductive

*FROM: The Science of Biology, P.B. Weisz and R.N. Keogh, Fifth Edition, McGraw-Hill, Inc., N.Y.