Part 18

In a word, Mueller appreciated fully the mystery of life, faced the problem of it directly, stated it in unequivocal terms, and by so doing saved the rising science of biology from wandering off into speculations which were seductive enough at that time, but which would have proved vain and wasteful of time and investigative energy. Mueller's influence on his students was sufficient in this matter to set the seal of vitalism, as it is called, on most of the biological work done in Germany about the middle of the century, and it was a recurrence to his observations and his methods which led the reaction to vitalistic theories that characterized the concluding years of the nineteenth century.

With regard to the significance of Mueller's work, Professor Du Bois-Reymond, himself a pupil of Mueller, in his memorial {243} address delivered before the Royal Academy of Sciences of Berlin in 1859, [Footnote 8] says: "It has been objected by those who insist on the greatness of Mueller's reputation that he himself made no discovery that can be said to be of the first rank. Mueller's fame is great enough for us to allow that there is something true in this objection. He accomplished more in developing the ideas of others than in original research of his own. That he did not make any great discovery is, however, rather due to the fact that he came at a time when great discoveries were no longer lying around loose as they had been in the preceding century, waiting to be made, as it were; and what he accomplished was of more value than one or two single discoveries of primary importance. He made the original ideas of other men so clear that they were at once accepted by all the medical and scientific world. In this way he furthered the progress of medicine better than any devotion, however successful, to one single feature could possibly have accomplished.

[Footnote 8: Gedaechtnissrede auf Johannes Mueller, von Emil Du Bois-Reymond, Berlin, Buckdruckerei der Koeniglichen Akademie der Wissenschaften (Dummler), 1860.]

"Mueller made mistakes, but then who ever fails to make mistakes in the face of nature? As a rule, however, he hit the nail on the head. There are many suggestive thoughts from him that the investigators of later times have proved to be true. He suggested, for instance, that there must necessarily be some connection between the ganglionic bodies and the nerve stems. He suggested, also, that there must be a special nerve system for the intestinal tract. Later discoveries in physiology have established both of these thoughts and have shown that Mueller had so entered into the spirit of nature and her processes as to be able to think her thoughts. There is no doubt that there are suggestions in {244} his writings, especially those of the later years of his life, which will give a series of triumphal substantiations of the same kind."

Du Bois-Reymond's final judgment is of special interest, because it tries to point out the comparative place that will be occupied by three great men in the biological sciences of a century ago:

"Haller and Mueller must be considered as giants of earlier days, though when future generations compare them with Cuvier they will occupy somewhat of the position that Galileo and Newton hold in comparison to La Place and Gauss, or Lavoisier in comparison to Berzelius. The first of these men had the opportunity to do great things while it was yet possible to do them, and left to their successors only the possibility of developing their thoughts." [Footnote 9]

[Footnote 9: Some idea of the estimation in which Mueller was held by his contemporaries, German and foreign, may be gathered from the number of scientific bodies of which he was a member. He was an associate in practically every serious scientific body in Germany. He was, besides, foreign member of the scientific academies at Stockholm, Munich, Brussels, Amsterdam; the scientific societies of Goettingen, London, Edinburgh, Copenhagen; foreign honorary member of the Academy of Sciences of Vienna; corresponding member of the Academies of St. Petersburg, Turin, Bologna, Paris and Messina; of the Society for Science at Upsala, of the Mecklenburg Naturalist Society of Rostock, of the Senkenberg Institute of Frankfort-on-Main, of the Academy of Natural Sciences of Philadelphia, of the Society of the Museum of Natural History at Strasbourg, of the Naturalists' Association of Dutch East India; member of the Holland Society of Sciences, Haarlem; of the Naturalist Society of Frieburg in Breisgau, Halle, Dantzig and Mainz; of the American Philosophical Society of Philadelphia, of the Society of Biology of Paris; honorary member of the Cambridge Philosophical Society, of the Natural Science Union of Hamburg, and the Natural Science Association of the Prussian Rheinland and Westphalia, of the American Academy of Arts and Sciences in Boston, of the Ethnological Society of London, of the Microscopic Association of Giessan, member of the Society for Science and Medicine at Heidelburg, of the Naturalists' Society at Dresden; corresponding member of the Scientific and Medical Association of Erlangen and Moscow; member of the Academy of Medicine of Paris; honorary member of the Academy of Medicine of Prague and of Dorpat, of the Medico-Chirurgical Academies of Wilna and of St. Petersburg, of the Medical Society of Guy's Hospital in London, of the Medical Society of Edinburgh and of the Hunterian Society of the same city, and of the Medico-Chirurgical Societies of London and of Zurich, of the Medical Societies of Budapest, of Lisbon, of Algiers and Constantinople; corresponding member of the Medico-Chirurgical Academy of Turin and of the Medical Society of Vienna.

Even this long list does not include all his various honorary and active memberships in scientific and medical societies. He was, besides, the laureate, that is, a prize winner, of the Medical Faculty of the University of Bonn, of the Soemmering Prize of the Senkenberg Institution, of the Copley Medal of the Royal Society of London, of the Culver Prize Monthyon of the same institution, as well as laureate of the Academy of Sciences of Vienna for Experimental Physiology. He had been honored by the King of Prussia by the conferment of the knighthood of the Order of the Red Eagle, by the King of Sweden by the Royal Swedish Order of the North Star, by the King of Bavaria by the Royal Bavarian Maximilian Order, and by the King of Sardinia by a knighthood in the Order of SS. Mauritius and Lazarus.]

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It is as a teacher that Mueller did his best work. He was not by nature a good talker and never said much, but he was very direct; and, as he spoke from the largest possible and most progressive knowledge of the subject, his lectures were always interesting to serious students. There seems to be a more or less general agreement that for the mass of his students he was uninteresting because likely to be above their heads. For the talented members of his class, however, he was an ideal teacher--always suggestive, always to the point, and eminently complete. Du Bois-Reymond says that he never was confused, never repeated himself, and never contradicted himself.

He was able to illustrate his lectures by sketches on the board in a way that enabled students to follow every step of {246} even a complex, embryological developmental process. He could trace, step by step, with the chalk, every stage of evolution in the organism and bring it clearly before his students. To a narrow circle of the best men within his class he became a personal friend, whose inspiration led them on to the deepest original researches. Among his students were some of the men who made German medicine and German science known all over the world in the last fifty years. Chief among them may be mentioned Virchow, Helmholtz, Du Bois-Reymond, Schwann, Lieberkuhn, the discoverer of the follicles in the intestines; Max Schultze, whose work in histology and physiology are well known; Claparede, Remak, Guido, Wagener, Lachmann and Reichert.

What he demanded of his students above all was that they should learn to help themselves. He set them tasks, gave them suggestions, directed their work, corrected their errors, but he wanted them to do work for themselves. His very presence was an inspiration. Both Virchow and Du Bois-Reymond speak of the power of his eye. Du Bois-Reymond says that there was in him an almost demoniac magic, and that students looked to him as the soldiers of the first Napoleon did when the great Emperor's words were in their ears--"Soldiers, the Emperor has his eye on you." Du Bois-Reymond adds that, consciously or unconsciously, every student felt the winning influence of his great personality. With all this he knew how to unbend, especially with favorite students, and many a joke from him found its way around the laboratory even during working hours. He was not one to stand on his dignity, and Virchow tells of him that even when nearly fifty he was known to race with a student down the corridor from one class-room door to another. He took up skating at the age of forty-five, and though he had not many friends and was too entirely devoted to his work to make {247} many acquaintances, it was always a source of pleasure to young men to be allowed to associate with him, and many eagerly sought the privilege.

How impressive a figure Mueller made in his character of teacher can be gathered best, perhaps, from a note added to Virchow's panegyric during its progress through the press, in which the pupil tells his impressions of the master:

"I must confess that Mueller, in his lectures and in his manner, reminded me of a Catholic priest, which might be accounted for by the impressions of his early childhood. When as the dean of the Faculty he mounted the _cathedra superior_, dressed in his official robes, and pronounced the Latin formulary of the proclamation of the doctors of medicine, with short, broken and contracted words; when he began his ordinary lectures in almost murmured syllables; or, when with religious earnestness he was discussing any of the abstruse questions of physiology, his tone and manner, his gestures and looks, all betrayed the traditional training of the Catholic priest."

Virchow adds, "Mueller himself was what he styled one of his greatest predecessors--perpetually a priest of nature. The religion which he served attached his pupils to him as it were by a sacred bond; and the earnest, priest-like manner of his speech and gestures completed the feeling of veneration with which everyone regarded him."

In the recently issued life of von Helmholtz, the great German physicist, his biographer makes it very clear how much Helmholtz thought of Mueller, one of the earliest teachers. [Footnote 10] Helmholtz, Bruecke, and Du Bois-Reymond were warm personal friends (college chums we would call them in America), and all fervent admirers of their greatest {248} master, who showed them, as Helmholtz says, "how thoughts arise in the brains of independent thinkers." A half-century later, in his recollections of the time, he said: "He who has come in contact with one or more men of the first rank has his mental intellectual standard for all time broadened, and such contact is the most interesting thing that life can hold." Curiously enough, one of the most interesting things in Helmholtz's recollections is that, despite the fact that the poverty of his parents made it advisable for him to get through his medical studies as soon as possible, Mueller persuaded him to take another year's medical work before going up for his graduation. This was mainly for the purpose of having his pupil complete an essay in physiology on which he was engaged. Mueller offered him the use of his own laboratory and all his instruments for this purpose. His judgment was justified by Helmholtz's wonderful work on the conservation of energy made within a few years after his graduation.

[Footnote 10: Herman von Helmholtz, von Leo Koenigsberger. Bd. 2, Braunschweig, Friedrich Viewig und Sohn, 1902-3]

Mueller's death was sudden, though not entirely unexpected. He had been ailing for many months and had resolved to give up his lectureship. He had made most of his preparations for settling up his affairs, and had even sent for his son, who was practising medicine at Cologne, to come up to see him. He made a special engagement for a consultation with his physician for a certain morning, and having gone to bed in reasonably good spirits, in fact, feeling better than he had for a long while, was found dead in the morning. Some time before he had made his will forbidding an autopsy, and so the exact cause of death will never be known, though it is rather easy to surmise that it was due to apoplexy, as arteriosclerosis--that is, degeneration of arteries--had been noticeable in Mueller for some years, and his temporal artery particularly had become hard and tortuous.

Mueller was buried with all the rites of the Church, and as {249} in Germany the ecclesiastical authorities are very strict in this matter, there can be no doubt that the great physiologist had been a faithful Catholic. He was known for his edifying attendance at Mass on all the Sundays of the year. Many years afterward, in the midst of the Kulturkampf in the early seventies, a monument was erected to him in his native Coblentz, and the occasion of its unveiling was taken by the Catholic Rhineland for a celebration in honor of their great scientist.

For a time, in his younger years, Mueller appears to have been not all unaffected by the materialistic tendencies so rife in the science of the time. His early anatomical investigations seem to have clouded somewhat his faith in things spiritual. One of the expressions attributed to him before his twenty-fifth year is that nothing exists in the human being which cannot be discovered by the scalpel. It was not long, however, before Mueller repudiated this expression and came back to a realization of the importance of the immaterial. Another expression attributed to him, "Nemo psychologus, nisi physiologus," "No one can be a psychologist, unless he is a physiologist," has been often repeated as if Mueller meant it in an entirely materialist sense. As a matter of fact, however, it is intended to convey only the idea that no one can really exhaust the science of psychology unless he knows the physiology of the brain, the organ which the mind uses in its functions in this life. The expression is really the foundation of the modern physiological psychology, which is by no means necessarily materialistic in its tendency, and has become a favorite subject of study even with those who appreciate thoroughly the importance of the immaterial side of psychology.

Mueller seems never to have gotten so far away from the Church as that other great physiologist of the succeeding generation in France, Claude Bernard, who for many years allowed himself to be swamped by the wave of materialism {250} so likely to seem irresistible to a scientist engaged in physiological researches. But, even Claude Bernard came back to the Church before the end, and, under the guidance of the great Dominican, Pere Didon, reached the realization that the only peace in the midst of the mysterious problem of life and the question of a hereafter is to be found in a submissive faith of the doctrines of Christianity.

Many years ago, when Virchow took it upon himself to say harsh words in public of Catholic scholarship, and to put forward the hampering influence of the Church on intellectual development as a reason for not allowing Catholics to have any weight in educational matters, the organ of the Catholics of Germany, _Germania_, reminded him that his own teacher, the great Johann Mueller, the acknowledged father of modern German medicine, and the founder of the fecund scientific method to which so many discoveries in the biological and medical sciences are due, had been brought up and educated a Catholic, had lived all the years of his productive scholarship and fruitful investigation in her bosom, and had died as an acknowledged son of the great mother Church.

Mueller is certainly one of the great names of nineteenth century science. When many another that seems now as well, or perhaps even better known, shall have been lost, his will endure, for his original researches represent the primal step in the great movement that has made possible the advances in nineteenth century medicine. He was honored by his contemporaries, venerated by the men of science who succeeded him; he has been enshrined in a niche for himself by posterity, and his name will remain as that of one of the great geniuses to whose inventive faculty the world owes some of those steps across the borderland into the hitherto unknown which seem so obvious once made, yet require a master mind to make and mean so much for human progress.

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THEODORE SCHWANN, FATHER OF THE CELL DOCTRINE

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My message is chiefly to you, Students of Medicine, since with the ideals entertained now your future is indissolubly bound. The choice lies open, the paths are plain before you. Always seek your own interests, make of a high and sacred calling a sordid business, regard your fellow-creatures as so many tools of trade, and, if your heart's desire is for riches, they may be yours; but you will have bartered away the birthright of a noble heritage, traduced the physician's well-deserved title of the Friend of Man, and falsified the best traditions of an ancient and honorable Guild. On the other hand, I have tried to indicate some of the ideals which you may reasonably cherish. No matter though they are paradoxical in comparison with the ordinary conditions in which you work, they will have, if encouraged, an ennobling influence, even if it be for you only to say with Rabbi Ben Ezra, "What I aspired to be and was not, comforts me." And though this course does not necessarily bring position or renown, consistently followed it will at any rate give to your youth an exhilarating zeal and a cheerfulness which will enable you to surmount all obstacles--to your maturity a serene judgment of men and things, and that broad charity without which all else is naught--to your old age that greatest of blessings, peace of mind, a realization, maybe, of the prayer of Socrates for the beauty in the inward soul and for unity of the outer and the inner man; perhaps, of the promise of St. Bernard, "Pax sine crimine, pax sine turbine, pax sine rixa." --Osler, _Teacher and Student, Aequanimitas_.

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THEODORE SCHWANN, FATHER OF THE CELL DOCTRINE.

It is one of the curious features of history that genuine worth of human accomplishment is almost in inverse ratio to the popularity it obtains in the generation in which it is produced. Supremely great work is rarely appreciated at anything like its proper value, by contemporaries. This principle is true apparently in all fields of human endeavor. In literature and in art it is a commonplace. But also, surprising though it may be, in science and in social betterment the rule holds a prominent place. It is nearly always the sign of only passing merit when any work secures the plaudits of its own generation. Brilliant theories are often immediately hailed with universal acclaim, while ground-breaking observations that are really great discoveries are apt to be neglected. The really new discovery is so novel that men cannot appreciate it at once. It is so different from their ordinary modes of thinking that they cannot place it properly. Its complete significance fails them.

This has been true for our nineteenth century biology almost more strikingly than for any other department of knowledge. Our many avenues of publicity instead of heralding abroad the great observations as soon as they have been made, in order to enable others to continue the work that the master mind has begun, have been only too constantly crowded with new opinions, novel theories, taking hypotheses, all attracting attention that they did not deserve. Men like Theodore Schwann, the father of the cell doctrine, are not apt to be so well known as the suggestor of some {254} striking bit of theory. Even the great biologists, such as Darwin himself, are known rather for their insubstantial theories than for their substantial additions to biological knowledge by patient observation and genial penetration into the secrets of nature. It is perhaps a warning to the modern physician who realizes this state of affairs, not to take the popular theories even in his own branch of biology as the current coin of truth. Theories pass, but observations endure. Auenbrugger's new method of tapping the chest in order to elicit its varying sounds looked even more childish than Galvani's acceptance of the position of dancing master to a frog, but their observations thus made continued the germs of undying truth.

While the name and the life of Theodore Schwann are but little known by the general public, his work is very thoroughly appreciated by those who have made special studies in biology, and few men in the progress of that science are considered to hold as high a place as that assigned to him. A study of the life of Schwann will serve to show not only that he eminently deserves this honor which has come to him, but will also bring into evidence the fact that his career deserves to be better known popularly, because it illustrates very well the typical mode of life in which great scientists are nurtured and the methods of investigation by which great discoveries are made.

Of the men who have made the biology of the nineteenth century there are three whose names stand out with special prominence. They are noted not for their controversial writing on mooted points, but for ground-breaking, original work of the highest scientific import. Their discoveries will preserve their memories for posterity long after the names of many of those to whom the glare of controversial publicity lent an ephemeral brightness for their own {255} generation shall have been forgotten. They are: Theodore Schwann, the anatomist, to whom modern biology owes its foundation by the establishment of the cell theory; Claude Bernard, the physiologist, to whom we are indebted for the great biological ideas of nervous inhibition and internal glandular secretion; finally Louis Pasteur, the chemist-bacteriologist, to whom is due the refutation of the annihilatory abiologic doctrine of spontaneous generation, and the discoveries that have revolutionized modern medicine and promise to accomplish as great a revolution in modern manufactures and industries.

It has often been said that the Catholic Church is opposed to scientific advance. It has especially been insisted that in what concerns biological science the Church's attitude has been distinctly discouraging. Recently the definite assertion has been made that no original thinker in science could continue in his profession of faith. Now, it so happens that all three of these men were born in the bosom of the Catholic Church, and were educated from their earliest years to maturity under her watchful care. Schwann and Pasteur remained in the midst of their great scientific triumphs her faithful sons. For years Bernard withdrew from all his old religious associations and became indifferent to the spiritual side of life, but before the end he came back to the knees of the Mother whose fostering care meant so much to him in early life.