Popular Science Monthly/Volume 86/February 1915/Thought in Science and in Science-Teaching
| THOUGHT IN SCIENCE AND IN SCIENCE-TEACHING |
By Dr. BENJAMIN C. GRUENBERG
JULIA RICHMOND HIGH SCHOOLS, NEW YORK
FOR the sciences as taught in the secondary schools in all parts of the country, there is generally claimed a "training" value in addition to the informational value. In common with the teachers of the so-called "humanities," many of the teachers of the natural sciences claim for their subjects the power to develop in the student certain intellectual and moral qualities. These highly desirable results are reputed to flow from the "mental discipline" involved in the effort to overcome difficulties, in the exact and orderly sequence of the intellectual material, and in the method of the laboratory.
Many psychologists deny outright the claim of any subject to have a disciplinary value. This denial is based deductively on certain modern generalizations as to the workings of the mind, or the break-down of the "faculty" hypothesis; it is based inductively on the results of certain experiments made in recent times, upon the effects of various learning processes. It is the purpose of these notes to base the denial of the general claim upon the results of observations on the mental processes of certain persons who may be presumed to have acquired the full benefits of whatever training the study of science is able to impart, namely, teachers of science. In addition, I wish to point out the direction in which I think it is worth while to look for "educational" results, as distinct from informational results.
Do teachers of science in general exhibit those special virtues which science learning is supposed to cultivate, in a degree above that shown by the average citizen? Or by the teachers of other subjects?
In the matter of observation, the teachers of science with whom I have come in contact are not more comprehensive than the teachers of history or of languages. The only criterion I have of this is "what kinds of phenomena are noted?" The science teachers are not more catholic in their interests or in their range of observations. On the contrary, I have found many teachers of history and of language who take an intelligent interest in the development of science, as well as in the phenomena that fall within their own specialties; but I know comparatively few teachers of science who take an intelligent interest in matters foreign to their specialties. And their observations, as gaged by their comments and conversation, are as restricted within their respective fields as are their interests beyond. If we consider the accuracy of the observations in their own fields, it remains an open question whether this accuracy is not itself a contributing factor in the selection of their specialties, rather than a result of pursuing the studies. But in so far as the ability to make minute observations on special material is the result of training, it may mean simply the acquisition of a special technique for running a fine-tooth comb over particular classes of objects, and not a general habit of taking in details at a glance. Teachers of physics are not especially acute in noting variations in the leaves of plants that they happen to pass; teachers of biology are not especially keen in observing delicate changes in the facial muscles; teachers of chemistry are not exceptionally alert in discovering the new fashionable angle for the cut of reveres. Whatever excellence of observation any of these may show seems to be confined either to the subject-matter or to the material in which the individual has a special interest. But this is just as true of mathematics teachers and of milliners, who never studied any "science" at all.
The method of science or of the science laboratory is supposed to develop a certain "instinct" for system or order. My observations do not support the expectation that science teachers are exceptionally orderly in their handling of materials. A working scientist must certainly have some sort of system in his head, but scientific work of a very high grade seems to be quite compatible with personal habits of a very high degree of disorderliness. Science teachers can not guarantee to the fond parents that the science courses will make the children any more careful about hanging up their hats and putting away the books than they were before. It is not to be denied that many individuals received from some well-conducted laboratory their first inspiration to make a place for everything and to keep everything in its place; but it is equally true that a successful science teacher may reside in the same skin as that occupied by a person who only occasionally gets his personal belongings into the right place—at home. At any rate, the science teachers that I happen to know are not as a class more systematic in their handling of materials than are the teachers of other subjects, or than the business men and housekeepers who never studied science at all. When we extend this principle of order to the matter of time, we find the same failure to generalize the training. Teachers of science within my experience are not more punctual in keeping engagements; they are not more prompt in setting to work when it is time to set to work, or in stopping when it is time to stop; they are not more systematic in planning the work of an hour or of a day. The individual variations seem to be as great among science teachers as among shoppers, and their general efficiency with respect to planning their time to the best advantage is exceeded by many housekeepers and clerks who lay no claim to special training.
When it comes to having system or order in the handling of ideas that are not parts of the routine work, I have found that science teachers are as easily bewildered and disconcerted by unfamiliar concepts as teachers of mathematics, and much more easily than teachers of history. This may mean that I happen to be acquainted with exceptionally clever teachers of history or with exceptionally stupid teachers of sciences; but it would not be fair to assume this. The general intelligence of the many teachers I have in mind (as this may be judged from casual intercourse in school, in committees, in general contact outside) does not show a correlation to the subjects taught.
The fact seems to be simply that the teacher of science is just as likely to become petrified under suitable conditions as the teacher of any other subject. So far as science teaching has gone in the past, it has not yet established a universally acting dynamic principle in the character or the mind of the student. Not only are new ideas met with hostility, but when he is forced to handle them the science teacher does not show that system in his attack which his training has putatively imparted. If he does show order in analyzing a problem in his own field, this may mean only that he has learned a useful formula for attacking certain types of problems. The value of the "training" should show itself when problems of new types are met.
This leads to the next virtue which science is expected to develop, namely, the judgment. We no doubt learn to judge by judging; but I have not found science teachers, in dealing with matters outside their specialties, exhibiting greater deliberation, broader vision or less prejudice than are shown by just ordinary people of "culture." On the contrary, the most complacent and immovable spirits I know are among teachers of science.
It is impossible, from the data at hand, to come to any final conclusion as to the causes of this apparent incompatibility between the results of science teaching, as shown by the teachers, and the possibilities of science teaching as claimed by these same teachers. But some of the causes are near the surface and are worth noting.
The concept science is not itself sufficiently definite, judging from the senses in which the word is used. Thus, one science teacher speaks of another as being "too scientific" in his teaching because the latter employs many technical terms in the class room. Technical terminology is here confused with "science"; and any person of common sense can tell you that it is not at all scientific to use in teaching such terms as make the work of the pupil unnecessarily difficult. Another teacher prides himself that he has a thorough scientific training, since he is able at a moment's notice to describe the laboratory technique for any experiment or demonstration you are likely to want; and his familiarity with this technique is the result of long and intensive laboratory experience. But we forget that a laboratory helper can acquire all these details without understanding either their pedagogical purpose or their theoretical significance. One science teacher speaks of another as being "well up" in science, because he knows the names of minerals or of spiders that you and I never heard of; or he knows all the stages in the life-history of some very rare red sea-weed. Here science is confused with erudition that happens to concern itself with objects of nature rather than with words out of books; but erudition is not science in the one case any more than in the other.
Another defect in much of our current science teaching lies in the fact that the method of the experiment, which is supposed to be one of the fundamentals in modern science, is often taught as a matter of manipulation rather than as a matter of thought. Thus, in presenting certain types of experiments, the negative instance or control is entirely ignored. A chemical test is given, let us say, for the identification of starch, or for determining its presence. The teacher shows that the addition of iodine solution to starch produces a blue color; the application is immediately made by placing some iodine on bread: the conclusion forced out of the minds of the unsuspecting victims is that bread contains starch! I quote from an elementary biology by well-known teachers:
2. Try the effect of iodine on each of the other food substances as follows: Put a small amount of grape sugar into a test tube; into a second tube put some white of egg (protein); into a third some fat or oil; into a fourth some mineral matter (salt); and into a fifth some water. Add a little water to each and boil as in 1 above to cook each nutrient. Add a drop or two of iodine solution to each tube.
Do any of the colors thus produced resemble at all the color resulting from the addition of iodine to starch?
3. From the preceding, state how you can determine whether or not a substance contains starch.Or we are to show that water is essential to the germination of seeds; and we are content to rest the case on the fact that seeds supplied with water did under certain—but undefined—conditions actually germinate; or we may accept the conclusion on the fact that seeds without water did not germinate—overlooking the equally obvious fact that certain seeds without soap-powder or star-dust also failed to germinate.
One biology teacher, after drilling the simple chemical tests for the nutrients, proceeded to apply the acquired knowledge in true pedagogical fashion, by testing an "unknown." The unknown proved to contain both starch and proteins. The application came when the teacher asked, "Well, then, is this substance fit to eat?" An affirmative answer was promptly forthcoming, and there ended that lesson. In an extensively used text-book of zoology, written by a biologist of international reputation, occurs this passage:
To one who looks upon an experiment as a means of testing hypotheses there is no obvious reason why "this experiment" can not be performed with a frog, or any other beast. But if the experiment is a means for getting certain desired objective results, of course it is impossible to get a complete frog to regenerate from an "excised representative sample"—as we know from experiments!
That the experiment does not always mean to the teacher the same as it does to the investigator may be inferred from the fact that many teachers are not averse to "faking" experiments that are arranged for demonstration purposes. William James tells in one of his papers of his own performance in a physiological demonstration, and he justifies it upon pragmatic grounds. The question I am raising is not one of ethics, but of clear thinking. If the experiment is a didactic tool for presenting concrete, objective processes, it falls into the same category as wall-charts and models. The demonstration experiment need not then be any more "real" than a glass model of the eye or of a diamond. But if the experiment is used by the teacher for the purpose of teaching method in thought or in the solution of problems, the "unsuccessful" experiment should be at least as illuminating and educating as the "successful" one.
A third source of confusion lies in the apparently harmless little word "law." A student of science should certainly know what is meant by a "law of nature"—but we may not expect him to if his teacher does not. Now it is altogether too common to hear teachers of science speak of the laws of nature in exactly the same way as ordinary folks whose notion of "law" is derived from the statutes of the commonwealth or the commandments of the gods. In science a law is presumably a generalization from a limited series of experiential data, not a prohibitive or mandatory order from some superior authority. Our attitude toward Boyle's law, for example, is in no way related to our loyalty to Mr. Boyle. In ordinary usage there may be violations of "law" and such violations are frequently followed by disagreeable consequences. But in "nature" the consequence is not something superimposed by way of punishment or retribution; it is itself a part of the law, and integral in the general process formulated in the law. Laws of nature can not be violated in the sense that statutory laws can be. Laws of health are descriptive generalizations of the conditions under which normal health is maintained. Yet we speak of empirical rules for securing these conditions as also being "laws of health." In practise we may or we may not observe these rules; but we can not violate the laws. Morbid conditions also arise in conformity to law. There is nothing unlawful or lawless in a curved spine or chronic constipation or an accidental poisoning. It is inconceivable that the ordinary pupil will get any very clear idea of "law in nature" from teaching that is as ambiguous as that of most teachers in the matter of law.
Ambiguous and misleading use of significant terms shows itself further in connection with ideas of causation—which certainly ought to be fundamental in science teaching. A teacher asks the question, "Why is air necessary to a plant?" Now this is a perfectly legitimate question if the meaning is "What is the relation of air to the maintenance of life in a plant?" But I have heard this and similar questions asked when the teachers' meaning was substantially, "What is the evidence that air is necessary, etc.?" In about three fourths of the cases the pupils will answer such a question by saying "Because the plant can not live without it." Teachers will frequently in such cases teach another answer—presumably the "right" one—but there will be no clearing up of thought.
Another type of question confuses a vague teleology with physiological principles of function, or with some ecological theory of adaptation. Thus, "Why has the grasshopper longer hind legs than the walking stick? Why has the rose-bush thorns? Why has a fly a shorter proboscis than the butterfly? Why has the bean-blossom a showier corolla than the oak?" These are actual examples of questions asked by teachers of biology in various schools. Strictly speaking, such a question means," How came this organism to have the character in question—organism here standing for species?" Which no one can answer. The pupil may have read or have heard of the speculations of Darwin or of Lamarck, but if he has, he should have been informed also that they were speculations. I have heard teachers who are regarded as of high merit asking such questions when they meant simply "What is the advantage such an animal has from this character?" Not only is the apparent utility, function or adaptation tacitly assumed by many teachers to explain the existence of organs or instinct, but the adaptation itself is assumed to be the "intention" or purpose of nature. The expression "nature's intention" is frequently heard in the class room. It may be impossible to speak in our public schools of the "purpose of God" without prejudice; but it does not seem to be a bit more scientific—and it is much more presumptuous—to speak of the "intention of Nature."
In the matter of intellectual honesty, does the teacher of science show any superiority over other teachers? The science teachers do not appear to me to be less prone than other teachers of my acquaintance to resort to indirect methods of accomplishing practical results. They do not appear to me to be less evasive in their dealings with subordinates or superiors. Pupils are constantly impelled to ask questions suggested by details in the lesson. Many of the questions are unanswerable in the form given, or in the present stage of our knowledge, or in the present state of the teacher's knowledge. How many teachers say frankly and unequivocally "I don't know"? I have failed to observe that science teachers are less given to that pedantic way of saying "I don't know" which the unsophisticated can not always interpret to mean just that. Here are a few of the questions that I have heard pupils ask of their science teachers without getting a direct answer, or the information that the teacher could not supply the answer, or a reference to some other source of information: Why does magnetism act only on certain kinds of metals? What makes roots and shoots respond to gravity in opposite senses? Why does not a grape-seed germinate inside the grape, where there is plenty of water? Why do sodium and potassium produce different colored flames? Any one can extend the list indefinitely. Many teachers have a favorite way of deferring these troublesome questions to "the next time" in the hope of gaining time for informing themselves—let us hope; or in the expectation that the question will be lost in the shuffle before next time. But the children are either clever enough to see through the trick, or unconsciously absorb the method of indirection to reenforce the lessons they have already learned from the iceman and the grocer.
Where science teachers come in contact with administrative activities, I have found them just as ready to accept the conventional evasions of the strict letter of the law for the purpose of achieving desired ends, as other teachers. And, on the other hand, I have found them just as ready to resort to the strict letter of the law for the purpose of evading the responsibility of making decisions or of taking initiative, as teachers of other subjects.
Teachers of biology—a subject that is supposed to be particularly saturated with the concepts of evolution, which postulate the principle of constant change—are among the most reactionary of my acquaintances. I know personally, more or less intimately, over three hundred teachers in high schools; about a third of these are science teachers. Of these science teachers only about a dozen have ever expressed any ideas that would indicate radically progressive notions in matters social, political, ethical, theological or educational; and more than that number have expressed attitudes that would be considered not merely "conservative," but positively regressive in each realm of thought.
The progressive teachers of my acquaintance are predominantly teachers of English and of mathematics. Even in matters purely technical, the majority of the science teachers that I know are either ignorant of the newer ideas about evolution, or extremely suspicious of anything that threatens to undermine the safe and sane doctrines that they acquired as students in college. They are temperamentally static and their "scientific training" has not made them any more open-minded or progressive. The science teachers of my acquaintance are not more open-minded or more free from prejudice than other teachers, or than other people in various occupational groups. The small number of science teachers who are open to new ideas are probably open-minded not because of their scientific training. The words foreigner, Jew and socialist, for example, produce in the minds of some four-score science teachers that I know the same kinds of reactions as they do in the minds of just ordinary chauvinists, hooligans and philistines, respectively.
In short, I have found no indication that these science teachers are more deliberate and analytical and systematic in forming judgments upon new problems than teachers of other subjects; nor that they are more progressive in adjusting themselves to new ideas—to say nothing of being on the look-out for new ideas; nor that they are freer from prejudices and conventions of thought.
However, notwithstanding the rather discouraging results of a canvass of my colleagues, I still believe that science teaching offers better opportunities for cultivating certain intellectual virtues than the teaching of other subjects,
A person temperamentally or habitually dishonest can not be expected to teach honesty, if indeed honesty can be taught at all. But even if honesty can not be taught at all, as some maintain, the laboratory presents the opportunity for learning to discriminate between certain truths and certain superficial resemblances to truth—which is in itself a great gain. That is, if a person is to be dishonest, it is desirable that he at least know that he is dishonest, so that he deceive not himself, however he may treat others.
The laboratory presents opportunities for testing objectively the accuracy and coherence of the pupil's language; it devolves upon the teacher to establish an ideal of accuracy. A number of pupils will come to a more or less conscious generalization of the idea, and a more or less deliberate acceptance of the ideal, without any assistance whatever; for most children, however, the teacher's help is needed or the experience in the laboratory will have no "training" value. In the laboratory, too, we may test the logic of a classification, for the inclusion of incompatibles or for the faulty distribution of coordinates, etc. Going through such an exercise a number of times will perhaps develop a certain skill that will show itself in the reduced time of the nth performance, but it will not establish a mental habit unless somehow the teacher makes the practise in such discrimination a part of the conscious purpose of the child.
The teachings of language are arbitrary; they exercise the memory (not in the gymnastic sense, of course) and cultivate faith in authorities. The teachings of mathematics are formal and deductive, and, as a rule, they leave no room for individual initiative or independence of thought. The teachings of history, so far as the facts are concerned, must also be more or less arbitrary and authoritative. But history teaching and language teaching, and even mathematics teaching, are rapidly becoming humanized in a modern, scientific sense.
The teaching of science, introduced into the schools in comparatively recent times, has been too much influenced by the methods of the older teachers of the older subjects. While the other subjects have felt the influence of the scientific age, the science teachers have failed to develop the possibilities of their own material. Science teaching needs indeed to be humanized, but not by being assimilated to the mechanical, formal teaching of the older school disciplines, but along the lines of its peculiar possibilities. We must not expect general discipline from special work in science; but we must turn to general application the special ideas and principles of science.
We can humanize our science teaching by relating it to the idea of human achievement. Achievement in science is an essential part of human history, and a very significant part. It can be made to appeal to the imagination and to stir the emotions quite as effectively, and to as good purpose, as achievement in other directions. The history teacher may be obliged to neglect this side of his history—at any rate, he generally does neglect it. But the science teacher can not afford to detach the great ideas which he wishes to impart from the animal species in the course of whose evolution these ideas emerged. We can humanize our science teaching by making clear the idea, and making it impressive, that human progress, as illustrated by the growth of science, depends upon most intimate kinds of cooperation; by making the pupils feel the interdependence of the living of all lands, by making them feel our dependence also upon those who have gone before. High-school girls and boys can appreciate the fact that the reason why one carried on the shoulders of another sees farther than the latter is not necessarily the superior optical apparatus of the first.
We can humanize our science teaching by making clear in the thought of the pupil the idea that the progress of science consists of a successive refinement of hypotheses; by teaching them to appreciate the difference between hypothesis and fact, on the one hand, and between fact and conclusion, on the other. We can teach an appreciation of the value of facts as the only sound basis for judgment, and we may hope to establish the habit of searching for facts during the suspension of judgment.
We can humanize science teaching by giving up the attempt to make scientists out of high-school students; that is not our function. It is our business not to make scientists, but to make as many children as possible appreciate first the service of science, and second the method of science—as a tried and worthy method of solving certain types of human problems. We may incidentally discover that here and there a pupil is worth directing into a scientific career; but that is a part of the general purpose of the school, and not of the specific purpose of science teaching. Now, if we are to make young people appreciate the service of science it will not be merely by establishing in their minds bonds of association between important inventions and the names of the inventors: it will be by making them feel the downright solidity of thoroughness and accuracy and honesty and clear vision. If we are to make them appreciate the method of science it will not be merely by helping them to memorize concrete facts, rules of procedure and abstract formulas, it will be by making them take part in analytical thinking about real problems until they have arrived at an explicit realization of what constitutes a valid way of thinking about problems.
We can humanize our science teaching by making the pupils realize that we have no final truth; that science, like life, is a constant becoming. This ought to do something to counteract what has been called the "superstition of science"—that attitude which continues the method of the medieval dialectician, but substitutes some new-sounding phrases for the older categories. The person who confounds evolution with the doctrine of natural selection, the one who has nothing to do with ions because these threaten to disrupt the atom which he acquired in his youth—these are among the men and women with closed systems of thought, who may indeed speak of chromosomes and valency, but who never are scientific.
We need science teachers more than ever. These should be first of all teachers. But the usual tests require that they shall be then familiar with reasonably large bodies of information about plants and animals, or about wheels and polarities, or about atoms and reactions. What is needed more than large bodies of information—which any reader can get out of a half-dozen books—is a habit of clear and honest thinking. This is not to say that the quality in question is not desirable in teachers of other subjects. It is simply to say that in the selection of teachers of science this qualification has been too greatly overlooked.