Popular Science Monthly/Volume 32/April 1888/Editor's Table
SCIENTIFIC HABITS OF THOUGHT.
IT is a question well worth considering, how scientific habits of thought are best to be formed, maintained, and strengthened. Such is the prestige of science in the present day, so thoroughly is scientific reasoning recognized as the type of all true reasoning, that nobody with any pretensions to intelligence would wish to be accused of thinking unscientifically. At the same time there is a vast amount of unscientific thinking being done on every hand; and men of almost every grade of culture may be found, the tone of whose minds is unscientific to the last degree. Let us see if we can throw into some kind of acceptable shape the general principles to be observed by whosoever would be saved from irrationality and a spirit of opposition to the truth — whosoever would wish to have scientific habits of thought in the best sense.
It is probably correct to say that science was first forced upon men's minds by the repeated presentation of the same phenomenon with an unvarying accompaniment of antecedent and consequent. Without entering upon a discussion of the nature of our conception of cause, we may say that science is nothing else than a knowledge of the permanent relations, whether causal or other, of things to one another. Nature, in the first place, forces us to recognize certain uniformities: some minds not only learn the particular lesson so taught, but, entering into the spirit of Nature's teaching, run on to discover further uniformities for themselves. These, to whatever age they belong, are the scientific spirits of their time. Others there are who look upon every such lesson as an infringement of their natural liberty to think and believe without any reference to the bounds of law. These learn only what they must, and, beyond the region of palpable and irresistible demonstration, love to indulge the most wayward and fantastic beliefs. In these we see the enemies of science, unwilling learners in Nature's school, rebellious spirits who fain would fashion the universe to their own liking. The first condition, therefore, of scientific thinking is to recognize and to bow to Nature as the supreme teacher, and to feel that she has an inexhaustible fund of wisdom to impart. He who thinks scientifically recognizes no authority save that of demonstration. lie gladly avails himself of the help of superior minds, but he does not swear by their words; for, great as they may be, and as he may acknowledge them to be, he can not regard them as infallible. Partisanship in science is almost a contradiction in terms. The expression "schools of thought" even is one to be accepted with caution; seeing that no one should wittingly attach himself to any school save the great school that Nature keeps ever open to all. Too much emphasis, indeed, can hardly be laid upon this view of the matter. The pursuit of truth partakes of the character of a religion; and the mind that is imbued with the religion of science never for a moment places any human authority, however great, in the place of the truth which, by no violent figure of speech, he may be said to adore. Truth has its ministers, but it has no priests, no class of men whose mere office summons to reverence. We ask respecting the ministers of truth simply how much of its illumination they have received, how much they are able to impart; and we honor them in proportion to the clearness and strength of their thought and the fruitfulness of their labors.
The more we dwell upon and develop the thought of Nature as the teacher, the more we see that the whole of scientific thinking depends upon loyalty to this one source of light. Every unscientific attitude of mind or movement of thought we ever heard of has had, for its main characteristic, an ignoring of Nature and a following after idols whose power was supposed to be superior to Nature. In all ages men have more or less resented the blessed bonds that have made them captive to earth and to its laws. Because their thought could traverse the heavens, and because their imagination could conjoin the most opposite elements and conditions, they have sighed after equal liberty for their active powers, and have run eagerly after whatever promised to emancipate them from the ordinary conditions of life. Hence the fanaticisms that have possessed and oppressed mankind; hence most of the delusions to which they have fallen subject; hence the scorn that, under certain systems of thought, has been, and is still, cast upon this present life; hence the prevailing indifference to, and depreciation of, what claims no higher sanction than natural or human law.
In the study of Nature there is one caution to be observed, and that is that absolute truth is not to be expected. Nature is willing to teach us, but she treats us like the children we are, using the symbols best suited to the range of our comprehension, but not laying bare her ultimate secrets. A large part of the scientific temper consists in recognizing this. He who imagines that, because he has made a generalization under which a certain group of facts can be advantageously presented and explained, he has struck the rock-bed of eternal truth, is a scholar rather pert than solid, and Nature will probably rebuke him some day. Newton knew well that in his great generalization he had merely succeeded in measuring a force the real nature of which it was wholly beyond him to explain; and the greatest scientific intellects of the present day are precisely those that most fully acknowledge, because they most deeply feel, the merely provisional character of the most important scientific hypotheses.
A third note of the scientific mind is practicality of view. The highest reverence for truth is not inconsistent with a desire to put truth to practical uses. Nature is the supreme teacher, and yet, from a certain point of view, Nature may be said to exist for us, not we for Nature. We lay hold of her phenomena with a masterful grasp, and read laws into them, reserving to ourselves the right to read ever wider and higher laws as our knowledge widens. And when our minds are in free and unrestrained movement, and are being built up in symmetry and strength by what they absorb in the study of external things, we feel that the highest work of which we can form any conception is being accomplished. There are scientific workers whose whole ambition seems to be to form a kind of hortus siccus of observations and opinions, and whose own minds are but little transformed by the knowledge that passes through them. These lack the true scientific spirit, though their work may at times have its uses. They lack the joy of growth, and never realize the sense, at once of liberty and power, which those possess who look upon nature, not as a mere curiosity-shop or museum, but as a vast domain providing all that is necessary for the exercise, aliment, and discipline of the human mind.
The truly scientific spirit, we may lastly say, is essentially inductive. It feels its way into truth by slow degrees. If facts are at all accessible, it does not care to depend on hypotheses; and it is always ready to accept the yoke of facts—never tries to put a yoke on facts. In this respect it differs greatly from the disposition shown by many radical thinkers of to-day, who, having thrown overboard their former theological opinions, are none the less governed in their daily thinkings by old theological methods. Such confidence have these persons in their argumentative that they never seem to care to freshen their thought with new knowledge. Such and such are the cardinal principles in which they believe, and from these they are prepared to draw an ever-lengthening chain of conclusions, all, as they hold, of absolute certainty because the starting-point was, in their opinion, indubitably true. No man, however, who has a glimmering of the scientific spirit cares to follow this kind of dead-reckoning. "He to whom the Eternal Word has spoken," says a famous mediæval sage, "is set free from many opinions." So he, we may say, to whom Nature has spoken in intimate tones, who knows what it is to have studied Nature patiently and faithfully, is freed from all bondage to mere opinions by his supreme attachment to truth. His great interest lies in knowing what is, not what, according to somebody's way of looking at things, ought to be.
We may know the man, therefore, whose habits of thought are scientific by his abiding faith in the teachings of Nature; by his unshaken conviction that the uniformities we see in the occurrence of phenomena are but hints of the universal constancy of natural law; by his interest in all that can be brought under law, and lack of interest in all alleged lawless and abnormal manifestations; by his recognition of the inaccessibility of absolute truth, and his willingness to make the best of provisional theories and symbols; by his freedom from pedantry and dilettanteism; by his reverence for human nature; by his constant desire for the verification of opinions, and his consequent freedom from all infatuation, whether for the theories of others or for his own. He is a man whose moderation is known to all men, whose patience seems to have been learned from Nature herself, whose thought moves from year to year in larger circles, and whose character bears witness to the liberal and elevated character of his daily occupations. Do all men of science, all professors of philosophy, conform fully to this type? No, but this is the type to which, in so far as they are true to the spirit of philosophy and science, they will all, gradually, more and more conform.
The death of Asa Gray removed a student who was looked up to in all the world of knowledge. In many aspects he had no master, and there were few who could be regarded as his peers. In his special field his leadership was recognized—in all nations. The help and sympathetic co-operation he gave to Darwin in building up the doctrine of variation and natural selection show him to have been a pioneer in the advance of science as a whole. His success in presenting the details of what was considered one of the driest of scientific subjects in such a way as to make his treatises as readable as a book of travels entitles him to a high position in literature. The company of American botanists who, having drunk their inspiration from his books, are carrying on their work in a like spirit, are a testimony to his powers as a teacher. And the Church, when it has purged itself from the heresy that every discovery in science overthrowing some old notion is an attack on religion, will be able to point to him as a man consistent and diligent in both spheres of life, to whom it never occurred that there was any conflict to be adjusted.
The history of learning is full of examples of men who have risen to eminence from the most incongruous surroundings, without adventitious aids, but solely by the force of their own impulses. Professor Gray affords another. His advantages were of the most limited character. His working life began with tending his father's tanbark mill, while he was distinguished as being the champion speller of his school district. Two years at a grammar-school, one year at the academy, and a medical course, constituted his entire formal education. He had no classical training, no scientific instruction further than was subsidiary to the medical studies of which he made no use. But he became one of the leading scientific men of his age, and, as Professor Dana remarks, "eminent for his graceful and vigorous English, the breadth of his knowledge, his classical taste, and the acuteness of his logical perceptions." An article in the "Edinburgh Encyclopædia" directed his attention to botany. He procured Professor Eaton's text-book, which was perhaps one of the best on the old system—but how different from the works of the series with which he made the science luminous!—and began his brilliant scientific career with the analysis of Claytonia Caroliniana. He must have been proficient in his studies, for we find him before the close of his medical course taking the place of the professors in lectures at Albany and Hamilton College. Then he became a regular teacher himself; was associated with Dr. Torrey in his researches; published his own investigations of the sedges and of the plants of northern and western New York; and prepared his first text-book, "The Elements," in 1836, a book in which, according to Professor Dana, the subjects of vegetable structure, physiology, and classification were presented in a masterly manner, and which "showed his customary independence of judgment and clear head in various criticisms and suggestions." The name of Professor Gray is intimately associated with Darwin's in the history of the theory of the origin of species. The series of letters from Darwin to Gray, contained in the recently published "Life and Letters" of Darwin and beginning on page 420 of the first volume, attest the respect Darwin had for his knowledge, the confidence which he reposed in his opinions, and the hearty fellowship that existed between them. Gray, Lyell, and Hooker were the three whose approval of his theory Darwin most desired to enjoy, and were the three to whom he earliest and most fully confided his views. Yet Gray and he did not agree entirely in their acceptance of the theory. While Darwin gave the predominant place to the environment in determining variation, Gray thought that the process worked more from within and was at most modified or limited by the external conditions. Darwin had extreme difficulty in accepting the conception of a Supreme Intelligence ordaining and controlling the process of evolution; Gray held to a complete harmony between the working of a Supreme Power and of evolution, and declared that "natural law is the human conception of continued and orderly divine action."
Professor Gray's "Statistics of the Flora of the United States" and his observations on the plants of Japan have an important bearing upon the theory of the origin of animal and vegetable life in the polar regions and their distribution thence down the continents, which is now advocated by biologists and paleontologists of high standing.
Professor Gray has not been conspicuous as a man of letters, but we may justly claim for his botanical works a place in literature as such. He contributed to the "American Journal of Science" biographical notices of deceased botanists and reviews of botanical work in which his accurate criticisms were tempered by a uniform kindliness of spirit, and he made considerable contributions to the "North American Review," "The Nation," and the "Atlantic Monthly." A volume of selections from these contributions, with a chapter on "Evolutionary Teleology," was published in 1876, under the title of "Darwiniana."
Professor Gray's personal character was admirably characterized by Darwin, who concluded, before he had even seen him, from reading some of his letters to Hooker, that he must be a man with something very lovable about him. A friend, paying a tribute to him in the London "Spectator," speaks warmly of his "singularly sweet and beautiful nature," and of "the freshness and brightness that recalled nothing but youth," of which not years nor learning, nor incessant studies, nor even the classification of the American Compositæ, could deprive him; and added that Darwin's son, to whom he sent a parcel of stamps to cheer his sickbed, "was not the only English child who received a like present from the same giver."
What the world of science thought of Asa Gray is attested by the honors which its schools and its societies conferred upon him, and by the respect, as to one having authority, in which he is invariably spoken of by its most distinguished writers. American feeling was reflected in the token which was presented to him a little more than two years ago by one hundred and eighty-five botanists, all in a sense his students, with Mr. Lowell's quatrain.
Professor Gray was taken away from the midst of his work. He had just completed a review of Darwin's "Life and Letters," had not quite finished the revision of his "Vitaceæ," and was busy with his "Necrology" for the "Journal of Science," when he was stricken.
One of the recognized evils attendant on the public-school system of this country is the insecurity of the tenure by which teachers hold their situations. So manifest an evil has this been that in certain States it has been proposed to remedy it by legislation. But, supposing the evil entirely removed, what would the result be? We can perhaps judge by what one of the best conducted of our educational journals says is the case in the great State of Illinois. We are not aware at this moment what is the law in that State respecting the appointment of teachers, but from what our contemporary, the "Illinois School Journal," says, some teachers, and other school officials as well, have only too strong a hold on the positions they fill. "One of these,"—we quote from the "Journal"—said the other day: "Why should I read books or bother my head to study about teaching? What will it profit me? My place is secure. I have as many friends as my principal or superintendent has. Let him try to remove mo if he dare." "There is much of this spirit," continues the "Journal," "in the schools, especially in the large cities. It is not among the teachers alone. It is among principals and superintendents as well. These people long since ceased to study and grow." So, hero is the dilemma: If the teacher has no security of tenure, he has no encouragement to throw himself heartily and earnestly into his work. If, on the other hand, he has, either through legal enactments or through his political associations, a firm hold upon his place, he is in danger of lapsing into the condition of mind and general disposition above described. It may be said that security of tenure, in the sense understood by the teachers, would not mean exemption from proper official supervision and authority, or an absolute right to employment in spite of proved disqualification; but, admitting this, it is still clear that, under such a system, the difficulty in the way of getting rid of indifferent or even of seriously deficient teachers would be very great. The "Illinois School Journal" says distinctly, and, as we think, truly, that we shall only be able to improve the schools when we have learned how to improve the teachers. What kind of material is offered, under the present system, for the teaching body we learn from a further article in the same periodical by a gentleman who states that he has been for years a member of the State Board of Examiners. "Experience," says this authority, "shows that many candidates fail on common English branches, particularly arithmetic and reading. . . . The papers show such deficiency in form as to indicate that teachers are extremely careless in this respect. The arrangement of work, the carelessness in regard to paragraphing, and even the use of capital letters, shows gross neglect of the proper usages of written language. Some show that they learned their spelling late in life, and that, when hurried, they revert to some juvenile form. . . . The worst and least excusable mistakes were in the definition of common words. Defining a noun by a verb, a verb by an adjective, an adjective by an adverb, was altogether too common. The derivation of words was hopelessly, painfully ridiculous." The examination papers in connection with which all this occurred are appended to the article from which we quote; and their extreme simplicity makes the statements of the article only the more surprising. The history, geography, arithmetic, and etymology are well within the compass of any fairly-taught lad of twelve or thirteen. Samples of the answers given are also furnished; and all we can say is that they well deserve a place beside Mark Twain's famous collection. One candidate who, in the paper on pedagogies, was asked to "define the terms subjective and objective as used in mental philosophy," answered that "we treat a topic subjectively when we take what we know of a subject and explain, without having any special object in view." Evidently, all that this individual knew of his "topic" would not have afforded a basis for much explanation, with or without an object in view. A very noticeable feature is the thorough dishonesty of many of the answers. Being asked to give the etymology of the word "urbane," one candidate said it was from ur, outside, and bane, city; another that it was from ur, a city, and bane, badly. Each of these would-be teachers and guides of the young knew that he, or she, was "guessing" in the most shameless manner — that is to say, practicing one of the very vices to which school-children are most prone, and which it is the duty of their teachers most earnestly to reprehend and repress.
Of course, it will be said that the worst cases of ignorance and incompetency were culled out by the examination; but the language of the article referred to indicates clearly enough that the general average of the candidates was low; and, if so, it may be assumed that many very poorly qualified persons crept through and got their certificates. And this is how the system is working to-day, when so many improvements on the old order of things are supposed to have been made. We greatly fear that, between the politics that make good teachers insecure, and bad ones secure, in their positions, and examinations that are largely farcical in their character, the interests of the rising generation are not being very intelligently or conscientiously studied. Good men and women no doubt there are, and many of them, engaged in the State schools; but these, we fear, can not avail to save the whole system from gravitating to that low point of efficiency which marks governmental action in all matters which lie outside the necessary and natural functions of government.