Science in Christian Perspective

A Physical Scientist Defines the Scientific
HENRY WEAVER, JR.
Eastern Mennonite College,
Harrisonburg, Virginia

From: JASA 7 (September 1955): 24-29.

I. Definition

If all the scientists present would write out their definition of Science it is quite probable that no two of them would be the same. The difference would most likely not only be a matter of words used, but we could expect a wide divergence in the scope of knowledge included in such definitions. It is certainly facetious for any one person to present a definition of science that is intended to represent the opinions of all scientists. To a lesser extent a similar problem is encountered in defining Physical Science as a more limited field of science. For that reason the boundaries of that area of science as presented here may be considered arbitrary.

Let us for the present limit our discussion of method to what is sometimes called the inorganic natural sciences. This would include physics, chemistry, astronomy, geology and certain parts of biology. It would exclude psychology, sociology, economics and certain parts of biology.

Futhermore let us consider only what is often termed non-formal science. That is we will consider only methods used to ascertain whether or not certain things are in actuality true. In other words we are talking about the methods which are commonly us by scientists to carefully investigate natural phenomena to determine what exists and the relationships an functions of that existence. The phenomena under investigation may have some immediate practical value or it may be fundamental information, the value of which is not currently apparent. 

II. There is not ONE Scientific Method. 

Science teachers have for years been talking about the Scientific Method. Certainly a good many people have the concept that there is a certain cut and dried pattern which is always followed in scientific investigation. The Harvard school² has recently taken exception to this point of view and I believe rightly so. If one takes the neat outline of the Scientific Method and tries to see how many of the monumental discoveries of science in the last hundred years fit it, he is in for a surprise. There is not just one rigid scientific method, but many methods which are valid and can be used to determine scientific truth.

This does not imply, however, that any slip-shod method can be used to determine physical science truth. Mavor³ suggests a fundamental principle when he says that the difference between science and common knowledge is in precision of observation and reasoning. In a general way we can say that science always uses the empirical method to determine truth. That is we rely on information received through one or more of our five senses as our fundamental source of truth.

Science however takes cognizance of certain limitations in the use of the senses to determine truth. Churchman4 suggests three such limitations. In the first place only controlled experiments are of value in determining truth. Optical illusions are familiar to us all. In uncontrolled experiments the other senses also play tricks on us at times. Secondly, in using our senses we assume certain things to be true and then either prove or disprove them by the consistency of the results. For example we assume that the mechanism of the speedometer in an automobile can register the speed of the car. We may make repeated, carefully controlled experiments to determine if this is so. In these tests we assume that our measuring devices and timing devices are accurate. If we find that at different speeds and conditions we consistently get comparable results we may conclude that the speedometer, the measuring equipment, and the timing apparatus are suitable equipment to help us make certain observations with our senses. Likewise we assume the validity of more abstract entities, and accept this validity because of the consistent results obtained. The third limitation, which incidentally was originally proposed by David Hume is that no Law of Science can ever be reached that is entirely free from doubt. While all available evidence may point to a certain conclusion there is always the possibility that some later evidence may negate that conclusion. The methods of science will give the answer that is most probably true, but they will not remove the possibility that the particular answer may not be true. This is part of the background for the statistical renaissance" that has in recent years changed the procedures of investigation in many fields of science. The importance of this will be clear, I am sure, after Dr. Dilworth's discussion.

At the same time that the scientist insists on the empirical method for ascertaining truth he makes use of scientific literature. Many, in fact probably most, of the facts of science with which a scientist- is acquainted have not been verified by his own senses. Inherent in this system of reporting and using scientific data is the principle of absolute integrity. Scientists use less than perfect equipment and are subject to human errors in observation, but it is a basic part of the method of science that the scientist reports only what he observes, and all that he observes with regard to a particular phenomenon, and that he attempts to determine the probable range of error to which his observations are subject. The effect of these observations on a particular theory or concept which he wishes to establish or disprove is inconsequental to his reporting of his observations. Furthermore the scientist needs to clearly distinguish between data and his conclusions based on that data. There are of course unethical scientists and some notable examples of frauds could be cited, but controlled experiments are usually subject to re-investigation and it is in this process or repeated study by different investigators that science has been able to maintain its integrity.

With this understanding of the principles that control the methods that may be used by scientists, it is not out of place to look at one specific method of science that is frequently outlined to students of science. This is not the only method of science, but it is one valid method. The steps are often given as Hypothesis, Theory and Law. First one forms an hypothesis. This is an explanation of some phenomena that the experimentor assumes on the basis of previous experiences of himself and others to be correct. For example there are at present many hypotheses concerning what causes a particular type of cancer. There is no set way in which one can come to hold a certain hypothesis. The genius of the man, his training, and certain accidental and often incidental factors combine to suggest it. It is in this sense that one can say that there is no one scientific method. However there is one specific thing to do with an hypothesis. That is to test it. If this hypothesis is true certain observable phenomena should result. The laboratory is a place to design and carry out experiments to see if the expected results follow. If they do not-guess again. i.e., try a new hypothesis. One is free to speculate. If the hypothesis is confirmed it is often then called a theory. If it is confirmed by a large number of investigators under a variety of conditions, and following various deductions based on the hypothesis, and over a considerable period of time, it may then be called a law. However the distinction between a theory and law is one of degree and there is no definite boundary between the two.

One might generalize a bit on what some have observed to be a variation in usual procedure between American and British research concerning this method. The American is more likely to proceed, without distracting side investigations, to prove or disprove his hypothesis. The Englishman is more inclined to follow any or every lead that comes along. As a result Americans may more quickly come to specific desired results, but the English will probably uncover more fundamental information. The Englishman who discovered penicillin5 did so because he was curious about a certain result quite incidental to the main purpose of the experiments he had underway. Certain AmericanS6 observed the same phenomena under similar circumstances, but did not take time to investigate them.

III. Scientific Language Conveys Unique Meanings

For one who is not a participant in scientific investigation to appreciate the methods of the scientists, it is necessary to recognize the unique way in which the English language is utilized by the scientist. Many very common words are adapted by scientists to convey very specialized meanings. To one who constantly uses these words in this particular sense, the specialized meaning becomes so familiar that he frequently fails to remember that the non-scientist will not get the same concept when these words are used to explain his discoveries. It is in this problem of communication that many of the misunderstandings between scientists and theologians have arisen, it seems to me.

Toulmin⁷ makes this point quite graphically by a consideration of the meaning of the scientific discovery that "light travels in straight lines." The two main words in this statement, "light" and "travels" both have different meanings in this statement from what they would have had to the average person in the day that this discovery was announced. Prior to that time "light" meant a lantern or perhaps a light spot made from the sun shining through the clouds. The simple statement of this discovery did not convey the idea of photons to the non-scientist. Like-wise the word "travel" did not convey the concept of motion of photons. It might have meant to the average person that light patches made by the sun shining through the clouds move across the ground in straight lines. Even now if I were to say, "look at that light moving outside" probably none of you would think about the motion of photons (which you couldn't observe) but you would look for a light source in motion. So it with most scientific discoveries, they represent a n concept that is described with old words with meanings.

FOOTNOTES

1. e.g. Karl Pearson.

2. James B. Conant, Science and Common Sense, Yale University press, 1951, chapter III.

3. James W. Mavor, General Biology, The Macmillian Co., New York, 1941, p3.