Popular Science Monthly/Volume 7/May 1875/Address to Medical Students
I AM glad of the privilege, gentlemen of the Medical College, of meeting to-day so many who are masters and students in the school of science. For if, as I believe, all our studies, whether of Nature or mind, are only chapters of one book, there can be nothing wiser in our day, when the growing mass of learning almost compels a microscopic research and somewhat of a microscopic bias—nothing wiser than at times to interchange our points of view. It is, indeed, one of the phases of that heredity, of which so much is said at present, that our callings bequeath their mental habits, so that the clergyman seems often born without the power of inductive reasoning, and the naturalist with a suspicion of all that cannot be analyzed by his blow-pipe. Yet I am sure that you are of a larger school than this; and in that feeling I venture to put before you a few thoughts on the mutual relations of scientific culture. I shall not try your patience by a treatise on the Mosaic cosmogony or evolution; and, indeed, I must ask your allowance beforehand, if I betray in my remarks that surface knowledge of gases or nervous tissues, not strange to one more busied with Greek aorists and primitive-church deposits. It is your noble calling to be students in that branch of science, perhaps the most fruitful of discovery to-day, which explores the laws of the highest organic life. If I can point out a few of the common features which give a meeting-ground with you for one who is, like myself, a physician of the soul—for studies that bear on the riddles of our mental life and the largest aims of moral education—my essay will not he thrown away.
It is plain to all that the marked feature of our modern culture is the enthusiastic study of Nature; and the fact demands our impartial thought. This change, even within the last thirty years, is a striking one. It comes in part from the magnificence of the discoveries gained in every part of natural inquiry. It comes again from the reaction of the mind, after a time of overstrained ideal pursuits; nor is it strange, when the philosophy which began with noble thinkers had evaporated at last into a misty pantheism, that we should ask a more robust sense, and a positive knowledge. It is amusing to meet to-day those who awhile ago were talking of the infinite soul in man, and are now quite proud of their pedigree from a West-African ape. But I attribute this feature of our culture not merely to such reaction. It betokens a solid growth in the method of inquiry. Although I distinguish it from many of the theories which call themselves science, yet the principle which begins with the study of facts, verifies them by sure experiment, and rests in ascertained laws, is the key of all discovery. Our modern intellect did not, indeed, originate it. Nor can I ever admit that the great thinkers of the past have not done immeasurable service in their spheres of knowledge; rather, I claim that there is not a single foundation truth, in regard to the mind or moral nature, which was not known, even before a Plato or an Augustine. Our philosophy does not give essential truth; it only opens it in its clearer relations. The fixed stars have shed the same light aforetime, although the glasses of to-day have pierced into the nebulous fields. But it is the peculiar character of natural science, and the grandeur of its march on this high-road, which have established, as never before, its critical method. You are familiar with this in the wide range of inductive study. The knowledge of the heavens is quite another thing to us than in the day when Aristotle reasoned from the ideal perfectness of the circle to the planetary motions; and "made the world," in Bacon's phrase, "out of his categories." Or, to illustrate from your own field, the ancient theories of material and spiritual substance, which led to such fruitless speculation even to recent days, have been exchanged for exact analysis.
But this method is not confined to the interpretation of Nature; it is the common law of advance in all knowledge. Mental science must now begin with the related facts of biology and psychology, in order to rise by clear analysis to the laws of thought or will. History obeys the same principle, and it has so passed, since the day of Niebuhr, out of the cloud-land of legend to terra firma. Our vast researches into language have come from the dismissal of the old hypothesis of a primitive tongue and the correlation of all the facts gathered from all the kindred forms of speech. It is the same with social science. And although I am aware of the notion of many doctors, both of divinity and medicine, that theology is a fixed deposit, as distinct from inductive knowledge, and indeed that there is an eternal conflict of religion and science, yet I am bold to say that it is a vulgar error. There is a more palpable movement in the science of Nature, because it has to do with material forces, while the theologian explores the more subtile laws of thought and moral history. We do not deal with scalpel or microscope, yet we recognize the method of analysis. It might be a curious pursuit if you should study medical history from the day of Galen, through the middle age, and note how the same speculative notions of soul and body entered into the current dogmas of the Church and the healing art. The central truths of Christianity are always the same; but Biblical criticism, the comparative study of Hebrew or Christian epochs, the domain of doctrinal thought, are growths of the human mind, and every advance has been the fruit of experimental searching. And if we have some clergymen as guiltless of modern ideas as the Englishman who moved the risibles of a scientific circle by claiming that the fossils of the caves were the bones of the rebel angels, possibly you may have a few doctors of medicine almost unable to appreciate the scientific criticism of the four Gospels.
But, as we have thus recognized this law of method as the fruit of our culture, we shall be able to see the interdependence of all these branches of knowledge. All our gains are helpful to each other. I might sum the vast history of science in a word—that it has taught us the harmony of law, not only in the correlation of natural forces, but of the moral and social forces of human life. But I look more especially at the studies which employ your profession, as they have shed such light on the marvelous secrets of the inner man. The cunning laws of cerebration; the wondrous rhythm that runs between the several powers of memory, feeling, will, and the sensitive nerve-centres; the dependence of thought on the supply of the chemical brain-food; the explanation of the riddles of our dream-life; the relation of our mental functions to the loss or decay of our organs; the phases of disease as affecting voluntary action—all these are as needful a study for the intellectual or the Christian thinker as for the naturalist. These researches have not only cured many mistakes of our psychology, but have given us sounder views of life and education. It is not too much to say that our theories of social and religious culture have been far too often affected by a partial view of our spiritual nature, which lost sight of its dependence on the body and the healthy laws of action. But while I gratefully acknowledge this debt, I hold that our scientific culture will, if faithful to its aim, lead us to a nobler knowledge of those truths that pass beyond a bald materialism. I can only touch here upon this wide subject. If I were to seek an argument against the modern deniers of a Divine Maker and Providence, I should turn to science itself as furnishing its best ground. The result of our study of Nature, it is justly claimed, is only the knowledge of phenomena; but in this claim science has rid us forever of the notion of material substance; it has resolved all into one original, persistent Force; it has thus lifted matter into a domain above the physical, and by its own induction brought us back to the necessary truth, which we can only interpret by our own personal intelligence and will. If evolution, whatever its amazing chain of growth, is forced to admit that the principal world-stuff has in it the capacity of all the thinking, conscious, moral being begotten from it, evolution is but a vague name for the living action of a living God. And when I sum, again, our results as to the human organism, all our knowledge of the fitness of the cerebral mass and each fibre of the spinal net-work to the motions of the unseen life, so far from proving thought a function of the brain, or will a shock of the nerve-power, has only refined the body into the perfect vehicle of the indwelling spirit. Nothing is more satisfying to a believer in facts above Nature than that chapter on the "Substance of the Mind," where the apostle of English Positivism, Mr. Spencer, gives us as the outcome of his analysis, that when we talk of material or spiritual substances, it is indifferent whether "we express those in terms of these, or these of those;" yet, as thought cannot be dissected like the gray matter of the brain, it is sounder science to say that the living force is another than the physical fact.
But I cannot linger on these questions. Enough if I look forward in this light to the most harmonious results. We need not expect at once a reconciliation of all discords. Much must be done before that is reached. The clergyman has to learn fully that the Word of God is to be studied as the oracle of the great truths of man's spiritual history, not rashly made the rule of exact science. The naturalist must learn that there are facts of conscience and of human life more sacred than the guesses of his theory, which he must touch with reverent hands. Indeed, I have sometimes thought if the clergy could ramble with Mr. Huxley over the glaciers, and Mr. Huxley would take an excursion into the fields of Christian history, we should have better clerical sermons, and better "lay sermons." Science will work its own cure at last. It is not probable that there will be less prayer on account of Mr. Tyndall's "prayer-gauge," so long as it is the bidding of the heart of man. It is not probable, if, as a witty doctor has lately hinted, we measure the varied genius of Homer, Spenser, or Beranger, by the slower or quicker respiration, that we shall read the "Iliad" or "Faerie Queene" with less delight. It is not probable that all our discoveries of the ape period will kindle our interest so much as the history we remember far better of the struggles and divine triumphs of the full-grown man. Let Science go on with its keenest analysis. It will return, when it is completed, to the living synthesis. If, with all our processes, we cannot manufacture a man, if even the mineral water we concoct is not quite the same as Nature brews in her laboratory, much more shall we give up the fruitless task of dissolving the ultimate facts of mind and life. I have been struck with a sentence of the late Mr. Mill, in his autobiography, where he speaks of a long stage of mental depression which destroyed his zeal for all his favorite studies. "I saw," he says, "that the habit of analysis tends to wear away the feelings. My education had failed to create these feelings in sufficient strength to resist this dissolving influence, while the whole course of my intellectual cultivation had made such analysis the inveterate habit of the mind. I was thus left stranded at the commencement of my voyage, with a well-equipped ship and a rudder, but no sail; without any desire for the ends I had been so carefully fitted to work for." That is the autobiography of our time, of its strength and of its weakness. Let such experience teach us the honest pursuit of science, but teach us also its limit. Our age will gather up the real gains of its knowledge. We shall have learned many of the laws of our being; we shall apply ourselves to a broader culture of the mind; we shall feel a more earnest interest in all aims for the improvement of the race. But we shall prize no less the treasures of letters and art bequeathed us by the past; the ideal truths which have employed the wise and good; and, above all, that Christian faith which has inspired the richest knowledge of mankind, and without which our best culture will be as dead as the fossils of a prehistoric cavern.
Such, gentlemen, is the result I anticipate for the next period of our scientific growth. Pardon me if I have given you too long or too dry an essay; but let me beg you to receive it as the conviction of one who feels a generous sympathy with all the real aims of his time. This is the best spirit of your noble profession. If you so pursue it, as honest interpreters of Nature and reverent worshipers of Him who is above Nature, you will make it a sacred ministry for not only physical knowledge, but for the service of God and man.
- Delivered recently to the graduating class of the New York College of Physicians and Surgeons.