Before Romanes, George H. Lewes, in his interesting monograph in the history of thought, "Aristotle, a Chapter in the History of Science," is quite as complimentary to the great Greek thinker. We may say that Lewes was by no means partial to Aristotle. Anything but inclined to accept authority as of value in philosophy, he had been rendered impatient by the fact that so much of the history of philosophy was dominated by Aristotle, and it was only that the panegyric was forced from him by careful study of all that the Stagirite wrote that he said: "History gazed on him with wonder. His intellect was piercing and comprehensive; his attainments surpa.s.sed those of every philosopher; his influence has been excelled only by the founders of religion ... his vast and active intelligence for twenty centuries held the world in awe."
Professor Osborn, whose scholarly study of the theory of evolution down the ages "From the Greeks to Darwin" rather startled the world of science by showing not only how old was a theory of evolution, but how frequently it had been stated and how many of them antic.i.p.ated phases of our own thought in the matter, pays a high compliment to the great Greek scientist. He says: "Aristotle clearly states and rejects a theory of the origin of adaptive structures in animals altogether similar to that of Darwin." He then quotes certain pa.s.sages from Aristotle"s "Physics,"
and says: "These pa.s.sages seem to contain absolute evidence that Aristotle had substantially the modern conception of the evolution of life, from a primordial, soft ma.s.s of living matter to the most perfect forms, and that even in these he believed that evolution was incomplete for they were progressing to higher forms."
Modern French scientists are particularly laudatory in their estimation of Aristotle. The group of biologists, Buffon, Cuvier, St. Hilaire, and others who called world attention to French science and its attainments about a century ago, are all of them on record in highest praise of Aristotle. Cuvier said: "I cannot read his work without being ravished with astonishment. It is impossible to conceive how a single man was able to collect and compare the mult.i.tude of facts implied in the rules and aphorisms contained in this book."
It is possible, however, to get opinions ardently laudatory of Aristotle from the serious students of any nation, provided only they know their Aristotle. Sir William Hamilton, the Scotch philosopher, said:
"Aristotle"s seal is upon all the sciences, his speculations have determined those of all subsequent thinkers." Hegel, the German philosophic writer, is not less outspoken in his praise: "Aristotle penetrated the whole universe of things and subjected them to intelligence." Kant, who is often said to have influenced our modern thinking more than any other in recent generations, has his compliment for Aristotle. It relates particularly to that branch of philosophy with which Kant had most occupied himself. The Koenigsberg philosopher said: "Logic since Aristotle, like Geometry since Euclid, is a finished science."
I do not want to tire you or I could quote many other authorities who proclaim Aristotle the genius of the race. They would include poets like Dante and Goethe, scholars like Cicero and Anthon, literary men like Lessing and Reich and many others. The scholars of the Middle Ages, far from condemnation for their devotion to Aristotle, deserve the highest praise for it. If they had done nothing else but appreciate Aristotle as our greatest modern scholars have done, that of itself would proclaim their profound scholarship.
The medieval writers are often said to have been uncritical in their judgment, but in their lofty estimation of Aristotle they displayed the finest possible critical judgment. On the contrary, the generations who made much of the opportunity to minimize medieval scholarship because of its worship at the shrine of Aristotle, must themselves fall under the suspicion at least of either not knowing Aristotle or of not thinking deeply about the subjects with regard to which he wrote. For in all the world"s history the rule has been that whenever men have thought deeply about a subject and know what Aristotle has written with regard to that subject, they have the liveliest admiration for the great Greek thinker.
This is true for philosophy, logic, metaphysics, politics, ethics, dramatics, but it is also quite as true for physical science. He lacked our knowledge, though not nearly to the degree that is usually thought, and he had a marvellous acc.u.mulation of information, but he had a breadth of view and a thoroughness of appreciation with a power of penetration that make his opinions worth while knowing even on scientific subjects in our enlightened age.
As for the supposed swearing by Aristotle, in the sense of literally accepting his opinions without daring to examine them critically, which is so constantly a.s.serted to have been the habit of the medieval scholars and teachers, it is extremely difficult in the light of the expressions which we have from them, to understand how this false impression arose. Aristotle they thoroughly respected. They constantly referred to his works, but so has every thinking generation ever since.
Whenever he had made a declaration they would not accept the contradiction of it without a good reason, but whenever they had good reasons, Aristotle"s opinion was at once rejected without compunction.
Albertus Magnus, for instance, said: "Whoever believes that Aristotle was a G.o.d must also believe that he never erred, but if we believe that Aristotle was a man, then doubtless he was liable to err just as we are." A number of direct contradictions of Aristotle we have from Albert. A well-known one is that with regard to Aristotle"s a.s.sertion that lunar rainbows appeared only twice in fifty years. Albert declared that he himself had seen two in a single year.
Indeed, it seems very clear that the whole trend of thought among the great teachers of the time was away from the acceptance of scientific conclusions on authority unless there was good evidence for them available. They were quite as impatient as the scientists of our time with the constant putting forward of Aristotle as if that settled a scientific question. Roger Bacon wanted the Pope to forbid the study of Aristotle because his works were leading men astray from the study of science, his authority being looked upon as so great that men did not think for themselves but accepted his a.s.sertions. Smaller men are always p.r.o.ne to do this, and indeed it const.i.tutes one of the difficulties in the way of advance in scientific knowledge at all times, as Roger Bacon himself pointed out.
These are the sort of expressions that are to be expected from Friar Bacon from what we know of other parts of his work. His "Opus Tertium"
was written at the request of Pope Clement IV, because the Pope had heard many interesting accounts of what the great thirteenth-century teacher and experimenter was doing at the University of Oxford, and wished to learn for himself the details of his work. Bacon starts out with the principle that there are four grounds of human ignorance. These are, "first, trust in inadequate authority; second, that force of custom which leads men to accept without properly questioning what has been accepted before their time; third, the placing of confidence in the a.s.sertions of the inexperienced; and fourth, the hiding of one"s own ignorance behind the parade of superficial knowledge, so that we are afraid to say I do not know." Professor Henry Morley, a careful student of Bacon"s writings, said with regard to these expressions of Bacon:
No part of that ground has yet been cut away from beneath the feet of students, although six centuries have pa.s.sed. We still make sheep-walks of second, third and fourth, and fiftieth hand references to authority; still we are the slaves of habit, still we are found following too frequently the untaught crowd, still we flinch from the righteous and wholesome phrase "I do not know" and acquiesce actively in the opinion of others that we know what we appear to know.
In his "Opus Majus" Bacon had previously given abundant evidence of his respect for the experimental method. There is a section of this work which bears the t.i.tle "Scientia Experimentalis." In this Bacon affirms that "without experiment nothing can be adequately known. An argument may prove the correctness of a theory, but does not give the cert.i.tude necessary to remove all doubt, nor will the mind repose in the clear view of truth unless it finds its way by means of experiment." To this he later added in his "Opus Tertium": "The strongest argument proves nothing so long as the conclusions are not verified by experience.
Experimental science is the queen of sciences, and the goal of all speculation."
It is no wonder that Dr. Whewell, in his "History of the Inductive Sciences," should have been unstinted in his praise of Roger Bacon"s work and writings. In a well-known pa.s.sage he says of the "Opus Majus":
Roger Bacon"s "Opus Majus" is the encyclopedia and "Novum Organon" of the thirteenth century, a work equally wonderful with regard to its wonderful scheme and to the special treatises by which the outlines of the plans are filled up.
The professed object of the work is to urge the necessity of a reform in the mode of philosophizing, to set forth the reasons why knowledge had not made greater progress, to draw back attention to the sources of knowledge which had been unwisely neglected, to discover other sources which were yet almost untouched, and to animate men in the undertaking of a prospect of the vast advantages which it offered. In the development of this plan all the leading portions of science are expanded in the most complete shape which they had at that time a.s.sumed; and improvements of a very wide and striking kind are proposed in some of the princ.i.p.al branches of study. Even if the work had no leading purposes it would have been highly valuable as a treasure of the most solid knowledge and soundest speculations of the time; even if it had contained no such details it would have been a work most remarkable for its general views and scope.
As a matter of fact the universities of the Middle Ages, far from neglecting science, were really scientific universities. Because the universities of the early nineteenth century occupied themselves almost exclusively with languages and especially formed students" minds by means of cla.s.sical studies, men in our time seem to be p.r.o.ne to think that such linguistic studies formed the main portion of the curriculum of the universities in all the old times and particularly in the Middle Ages. The study of the cla.s.sic languages, however, came into university life only after the Renaissance. Before that the undergraduates of the universities had occupied themselves almost entirely with science. It was quite as much trouble to introduce linguistic studies into the old universities in the Renaissance time to replace science, as it was to secure room for science by pushing out the cla.s.sics in the modern time.
Indeed the two revolutions in education are strikingly similar when studied in detail. Men who had been brought up on science before the Renaissance were quite sure that that formed the best possible means of developing the mind. In the early nineteenth century men who had been formed on the cla.s.sics were quite as sure that science could not replace them with any success.
There is no pretence that this view of the medieval universities is a new idea in the history of education. Those who have known the old universities at first hand by the study of the actual books of their professors and by familiarity with their courses of study, have not been inclined to make the mistake of thinking that the medieval university neglected science. Professor Huxley in his "Inaugural Address as Rector of Aberdeen University" some thirty years ago stated very definitely his recognition of medieval devotion to science. His words are well worth remembering by all those who are accustomed to think of our time as the first in which the study of science was taken up seriously in our universities. Professor Huxley said:
The scholars of the medieval universities seem to have studied grammar, logic, and rhetoric; arithmetic and geometry; astronomy, theology, and music. Thus their work, however imperfect and faulty, judged by modern lights, it may have been, brought them face to face with all the leading aspects of the many-sided mind of man. For these studies did really contain, at any rate in embryo, sometimes it may be in caricature, what we now call philosophy, mathematical and physical science, and art. _And I doubt if the curriculum of any modern university shows so clear and generous a comprehension of what is meant by culture, as this old Trivium and Quadrivium does._
It would be entirely a mistake, however, to think that these great writers and teachers who influenced the medieval universities so deeply and whose works were the text-books of the universities for centuries after, only had the principles of physical and experimental science and did not practically apply them. As a matter of fact their works are full of observation. Once more, the presumption that they wrote only nonsense with regard to science comes from those who do not know their writings at all, while great scientists who have taken the pains to study their works are enthusiastic in praise. Humboldt, for instance, says of Albertus Magnus, after reading some of his works with care:
Albertus Magnus is equally active and influential in promoting the study of natural science and of the Aristotelian philosophy. His works contain some exceedingly acute remarks on the organic structure and physiology of plants. One of his works bearing the t.i.tle of "Liber Cosmographicus De Natura Locorum" is a species of physical geography. I have found in it considerations on the dependence of temperature concurrently on lat.i.tude and elevation and on the effect of different angles of the sun"s rays in heating the ground which have excited my surprise.
It is with regard to physical geography of course that Humboldt is himself a distinguished authority.
Humboldt"s expression that he found some exceedingly acute remarks on the organic structure and physiology of plants in Albert the Great"s writings will prove a great surprise to many people. Meyer, the German historian of botany, however, has re-echoed Humboldt"s praise with emphasis. The extraordinary erudition and originality of Albert"s treatise on plants drew from Meyer the comment:
No botanist who lived before Albert can be compared with him unless Theophrastus, with whom he was not acquainted; and after him none has painted nature in such living colors or studied it so profoundly until the time of Conrad Gessner and Caesalpino.
These men, it may be remarked, come three centuries after Albert"s time.
A ready idea of Albert"s contributions to physical science can be obtained from his life by Sighart, which has been translated into English by Dixon and was published in London in 1870. Pagel, in Puschmann"s "History of Medicine," already referred to, gives a list of the books written by Albert on scientific matters with some comments which are eminently suggestive, and furnish solid basis for the remark that I have made, that men"s minds were occupied with nearly the same problems in science in the thirteenth century as we are now, while the conclusions they came to were not very different from ours, though reached so long before us.
This catalogue of Albertus Magnus" works shows very well his own interest and that of his generation in physical science of all kinds.
There were eight treatises on Aristotle"s physics and on the underlying principles of natural philosophy and of energy and of movement; four treatises concerning the heavens and the earth, one on physical geography which also contains, according to Pagel, numerous suggestions on ethnography and physiology. There are two treatises on generation and corruption, six books on meteors, five books on minerals, three books on the soul, two books on the intellect, a treatise on nutritives, and then a treatise on the senses and another on the memory and on the imagination. All the phases of the biological sciences were especially favorite subjects of his study. There is a treatise on the motion of animals, a treatise in six books on vegetables and plants, a treatise on breathing things, a treatise on sleep and waking, a treatise on youth and old age, and a treatise on life and death. His treatise on minerals contains, according to Pagel, a description of ninety-five different kinds of precious stones. Albert"s volumes on plants were reproduced with Meyer, the German botanist, as editor (Berlin, 1867). All of Albert"s books are available in modern editions.
Pagel says of Albertus that
His profound scholarship, his boundless industry, the almost incontrollable impulse of his mind after universality of knowledge, the many-sidedness of his literary productivity, and finally the almost universal recognition which he received from his contemporaries and succeeding generations, stamp him as one of the most imposing characters and one of the most wonderful phenomena of the Middle Ages.
In another pa.s.sage Pagel has said:
While Albert was a Churchman and an ardent devotee of Aristotle, in matters of natural phenomena he was relatively unprejudiced and presented an open mind. He thought that he must follow Hippocrates and Galen, rather than Aristotle and Augustine, in medicine and in the natural sciences. We must concede it a special subject of praise for Albert that he distinguished very strictly between natural and supernatural phenomena. The former he considered as entirely the object of the investigation of nature. The latter he handed over to the realm of metaphysics.
Roger Bacon is, however, the one of these three great teachers who shows us how thoroughly practical was the scientific knowledge of the universities and how much it led to important useful discoveries in applied science and to antic.i.p.ations of what is most novel even in our present-day sciences. Some of these indeed are so startling, that only that we know them not by tradition but from his works, where they may be readily found without any doubt of their authenticity, we should be sure to think that they must be the result of later commentators" ideas.
Bacon was very much interested in astronomy, and not only suggested the correction of the calendar, but also a method by which it could be kept from wandering away from the actual date thereafter. He discovered many of the properties of lenses and is said to have invented spectacles and announced very emphatically that light did not travel instantaneously but moved with a definite velocity. He is sometimes said to have invented gunpowder, but of course he did not, though he studied this substance in various forms very carefully and drew a number of conclusions in his observations. He was sure that some time or other man would learn to control the energies exhibited by explosives and that then he would be able to accomplish many things that seemed quite impossible under present conditions.
He said, for instance:
Art can construct instruments of navigation, such that the largest vessels governed by a single man will traverse rivers and seas more rapidly than if they were filled with oarsmen.
One may also make carriages which without the aid of any animal will run with remarkable swiftness.
In these days when the automobile is with us and when the princ.i.p.al source of energy for motor purposes is derived from explosives of various kinds, this expression of Roger Bacon represents a prophecy marvellously surprising in its fulfilment. It is no wonder that the book whence it comes bears the t.i.tle "De Secretis Artis et Naturae." Roger Bacon even went to the extent, however, of declaring that man would some time be able to fly. He was even sure that with sufficient pains he could himself construct a flying machine. He did not expect to use explosives for his motor power, however, but thought that a windla.s.s properly arranged, worked by hand, might enable a man to make sufficient movement to carry himself aloft or at least to support himself in the air, if there were enough surface to enable him to use his lifting power to advantage. He was in intimate relations by letter with many other distinguished inventors and investigators besides Peregrinus and was a source of incentive and encouragement to them all.
The more one knows of Aquinas the more surprise there is at his antic.i.p.ation of many modern scientific ideas. At the conclusion of a course on cosmology delivered at the University of Paris he said that "nothing at all would ever be reduced to nothingness" (_nihil omnino in nihilum redigetur_). He was teaching the doctrine that man could not destroy matter and G.o.d would not annihilate it. In other words, he was teaching the indestructibility of matter even more emphatically than we do. He saw the many changes that take place in material substances around us, but he taught that these were only changes of form and not substantial changes and that the same amount of matter always remained in the world. At the same time he was teaching that the forms in matter by which he meant the combinations of energies which distinguish the various kinds of matter are not destroyed. In other words, he was antic.i.p.ating not vaguely, but very clearly and definitely, the conservation of energy. His teaching with regard to the composition of matter was very like that now held by physicists. He declared that matter was composed of two principles, prime matter and form. By _forma_ he meant the dynamic element in matter, while by _materia prima_ he meant the underlying substratum of material, the same in every substance, but differentiated by the dynamics of matter.
It used to be the custom to make fun of these medieval scientists for believing in the trans.m.u.tation of metals. It may be said that all three of these greatest teachers did not hold the doctrine of the trans.m.u.tation of metals in the exaggerated way in which it appealed to many of their contemporaries. The theory of matter and form, however, gave a philosophical basis for the idea that one kind of matter might be changed into another. We no longer think that notion absurd. Sir William Ramsay has actually succeeded in changing one element into another and radium and helium are seen changing into each other, until now we are quite ready to think of trans.m.u.tation placidly. The Philosopher"s Stone used to seem a great absurdity until our recent experience with radium, which is to some extent at least the philosopher"s stone, since it brings about the change of certain supposed elements into others. A distinguished American chemist said not long ago that he would like to extract all the silver from a large body of lead ore in which it occurs so commonly, and then come back after twenty years and look for further traces of silver, for he felt sure that they would be found and that lead ore is probably always producing silver in small quant.i.ties and copper ore is producing gold.
Most people will be inclined to ask where the fruits of this undergraduate teaching of science are to be found. They are inclined to presume that science was a closed book to the men and women of that time. It is not hard, however, to point the effect of the scientific training in the writings of the times. Dante is a typical university man of the period. He was at several Italian universities, was at Paris and perhaps at Oxford. His writings are full of science. Professor Kuhns, of Wesleyan, in his book "The Treatment of Nature in Dante," has pointed out how much Dante knows of science and of nature. Few of the poets not only of his own but of any time have known more. There are only one or two writers of poetry in our time who go with so much confidence to nature and the scientific interpretation of her for figures for their poetry. The astronomy, the botany, the zoology of Albertus Magnus and Thomas Aquinas, Dante knew very well and used confidently for figurative purposes. Anyone who is inclined to think nature study a new idea in the world forgets, or has never known, his Dante. The birds and the bees, the flowers, the leaves, the varied aspects of clouds and sea, the phenomena of phosph.o.r.escence, the intimate habits of bird and beast and the ways of the plants, as well as all the appearances of the heavens, Dante knew very well and in a detail that is quite surprising when we recall how little nature study is supposed to have attracted the men of his time. Only that his readers appreciated it all, Dante would surely not have used his scientific erudition so constantly.
So much for the undergraduate department of the universities of the Middle Ages, and the view is absolutely fair, for these were the men to whom the students flocked by thousands. They were teaching science, not literature. They were discussing physics as well as metaphysics, psychology in its phenomena as well as philosophy, observation and experiment as well as logic, the ethical sciences, economics, practically all the scientific ideas that were needed in their generation--and that generation saw the rise of the universities, the finishing of the cathedrals, the building of magnificent town halls and castles and beautiful munic.i.p.al buildings of many kinds, including hospitals, the development of the Hansa League in commerce, and of wonderful manufacturers of all the textiles, the arts and crafts, as well as the most beautiful book-making and art and literature. We could be quite sure that the men who solved all the other problems so well could not have been absurd only in their treatment of science. Anyone who reads their books will be quite sure of that.
While most people might be ready, then, to confess that possibly Huxley was not mistaken with regard to the undergraduate department of the universities, most of them would feel sure that at least the graduate departments were sadly deficient in accomplishment. Once more this is entirely an a.s.sumption. The facts are all against any such idea.
There were three graduate departments in most of the universities--theology, law, and medicine. While physical scientists are usually not cognizant of it apparently, theology is a science, a department of knowledge developed scientifically, and most of these medieval universities did more for its scientific development than the schools of any other period. Quite as much may be said for philosophy, for there are many who hesitate to attribute any scientific quality to modern developments in the matter. As for law, this is the great period of the foundation of scientific law development; the English common law was formulated by Bracton, the deep foundations of basic French and Spanish law were laid, and canon law acquired a definite scientific character which it was always to retain. All this was accomplished almost entirely by the professors in the law departments of the universities.
It was in medicine, however, where most people would be quite sure without any more ado that nothing worth while talking about was being done, that the great triumphs of graduate teaching at the medieval universities were secured. Here more than anywhere else is there room for supreme surprise at the quite unheard-of antic.i.p.ations of our modern medicine and, stranger still, as it may seem, of our modern surgery.
The law regulating the practice of medicine in the Two Sicilies about the middle of the thirteenth century shows us the high standard of medical education. Students were required to have three years of preliminary study at the university, four years in the medical department, and then practise for a year with a physician before they were allowed to practise for themselves. If they wanted to practise surgery, an extra year in the study of anatomy was required. I published the text of this law, which was issued by the Emperor Frederick II about 1241, in the _Journal of the American Medical a.s.sociation_ three years ago. It also regulated the practice of pharmacy. Drugs were manufactured under the inspection of the government and there was a heavy penalty for subst.i.tution, or for the sale of old inert drugs, or improperly prepared pharmaceutical materials. If the government inspector violated his obligations as to the oversight of drug preparations the penalty was death. Nor was this law of the Emperor Frederick an exception. We have the charters of a number of medical schools issued by the Popes during the next century, all of which require seven years or more of university study, four of them in the medical department, before the doctor"s degree could be obtained. When new medical schools were founded they had to have professors from certain well-recognized schools on their staff at the beginning in order to a.s.sure proper standards of teaching, and all examinations were conducted under oath-bound secrecy and with the heaviest obligations on professors to be a.s.sured of the knowledge of students before allowing them to pa.s.s.
It might be easy to think, and many people are p.r.o.ne to do so, that in spite of the long years of study required there was really very little to study in medicine at that time. Those who think so should read Professor Clifford Allb.u.t.t"s address on the "Historical Relations of Medicine and Surgery" delivered at the World"s Fair at St. Louis in 1904. He has dwelt more on surgery than on medicine, but he makes it very clear that he considers that the thinking professors of medicine of the later Middle Ages were doing quite as serious work in their way as any that has been done since. They were carefully studying cases and writing case histories, they were teaching at the bedside, they were making valuable observations, and they were using the means at their command to the best advantage. Of course there are many absurdities in their therapeutics, but then we must not forget there have always been many absurdities in therapeutics and that we are not free from them in our day. Professor Richet, at the University of Paris, said not long ago: "The therapeutics of any generation is quite absurd to the second succeeding generation." We shall not blame the medieval generations for having accepted remedies that afterwards proved inert, for every generation has done that, even our own.
Their study of medicine was not without lasting accomplishment, however.
They laid down the indications and the dosage for opium. They used iron with success, they tried out many of the bitter tonics among the herbal medicines, and they used laxatives and purgatives to good advantage.
Down at Montpellier, Gilbert, the Englishman, suggested red light for smallpox because it shortened the fever, lessened the lesions, and made the disfigurement much less. Finsen was given the n.o.bel prize partly for re-discovery of this. They segregated erysipelas and so prevented its spread. They recognized the contagiousness of leprosy, and though it was probably as widespread as tuberculosis is at the present time, they succeeded not only in controlling but in eventually obliterating it throughout Europe.
It was in surgery, however, that the greatest triumphs of teaching of the medieval universities were secured. Most people are inclined to think that surgery developed only in our day. The great surgeons of the thirteenth and fourteenth centuries, however, antic.i.p.ated most of our teaching. They investigated the causes of the failure of healing by first intention, recognized the danger of wounds of the neck, differentiated the venereal diseases, described rabies, and knew much of blood poisoning, and operated very skilfully. We have their text-books of surgery and they are a never-ending source of surprise. They operated on the brain, on the thorax, on the abdominal cavity, and did not hesitate to do most of the operations that modern surgeons do. They operated for hernia by the radical cure, though Mondeville suggested that more people were operated on for hernia for the benefit of the doctor"s pocket than for the benefit of the patient. Guy de Chauliac declared that in wounds of the intestines patients would die unless the intestinal lacerations were sewed up, and he described the method of suture and invented a needle holder. We have many wonderful instruments from these early days preserved in pictures at least, that show us how much modern advance is merely re-invention.