The Popes and Science Part 14

Albert the Great was indeed a thoroughgoing experimentalist in the best modern sense of the term. He says in the second book of his treatise On Minerals (De Mineralibus): "The aim of natural science is not simply to accept the statements of others, that is, what is narrated by people, but to investigate the causes that are at work in nature for themselves." When we take this expression in connection with the other, that "we must endeavor to find out what nature can naturally bring to pa.s.s," the complete foundation of experimentalism is laid. Albert held this principle not only in theory, but applied it in practice.

It is often said that the scholastic philosophers, and notably Albertus Magnus and Thomas Aquinas, almost idolatrously worshipped at the shrine of Aristotle, and were ready to accept anything that this great Greek philosopher had taught. We have already quoted Roger Bacon's request to the Pope to forbid the study of the Stagirite. It is interesting to find in this regard, that while Albert declared that in questions of natural science he would prefer to follow Aristotle to St. Augustine--a declaration which may seem surprising to many people {298} who have been p.r.o.ne to think that what the Fathers of the Church said medieval scholars followed slavishly--he does not hesitate to point out errors made by the Greek philosopher, nor to criticise his conclusions very freely. In his Treatise on Physics, [Footnote 34] he says, "whoever believes that Aristotle was a G.o.d must also believe that he never erred. But if one believe that Aristotle was a man, then doubtless he was liable to err just as we are." In fact, as is pointed out by the Catholic Encyclopaedia in its article on Albertus Magnus, to which we are indebted for the exact reference of the quotations that we have made, Albert devotes a lengthy chapter in his Summa Theologiae [Footnote 35] to what he calls the errors of Aristotle. His appreciation of Aristotle is always critical. He deserves great credit not only for bringing the scientific teaching of the Stagirite to the attention of medieval scholars, but also for indicating the method and the spirit in which that teaching was to be received.

[Footnote 34: Physica, lib. VIII., tr. i., xiv.]

[Footnote 35: Summa Theologiae, Pars II., tr. i., Quaest iv.]

With regard to Albert's devotion to the experimental method and to observation as the source of knowledge in what concerns natural phenomena, Julius Pagel, in his History of Medicine in the Middle Ages, which forms one of the parts of Puschmann's Handbook of the History of Medicine, has some very interesting remarks that are worth while quoting here: "Albert," he says, "shared with the naturalists of the scholastic period the quality of entering deeply and thoroughly into the objects of nature, and was not content with bare superficial details concerning them, which many of the writers of the period penetrated no further than to provide a nomenclature. While Albert was a churchman and an {299} 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 as 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."

"Albert's efforts" Pagel says, "to set down the limits of natural science shows already the seeds of a more scientific treatment of natural phenomena, and a recognition of the necessity to know things in their causes--_rerum cognoscere causas_--and not to consider that everything must simply be attributed to the action of Providence. He must be considered as one of the more rational thinkers of his time, though the fetters of scholasticism still bound him quite enough, and his mastery of dialectics, which he had learned from the strenuous Dominican standpoint, still made him subordinate the laws of nature to the Church's teaching in ways that suggested the possibility of his being less free than might otherwise have been the case. His thoroughgoing piety, his profound scholarship, his boundless industry; the almost uncontrollable impulse of his mind after universality of knowledge; his many-sidedness in literary productivity; and finally the 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."

Perhaps in no department of the history of science {300} has more nonsense been talked, than with regard to the neglect of experiment and observation in the Middle Ages. The men who made the series of experiments necessary to enable them to raise the magnificent Gothic cathedrals; who built the fine old munic.i.p.al buildings and abbeys and castles; who spanned wide rivers with bridges, and yet had the intelligence and the skill to decorate all of these buildings as effectively as they did,--cannot be considered either as impractical or lacking in powers of observation. As I show in the chapter The Medieval University Man and Science, Dante, the poet and literary man of the thirteenth century, had his mind stored with quite as much material information with regard to physical science and nature study, as any modern educated man. It is true that the men of the Middle Ages did not make observations on exactly the same things that we do, but to say either that they lacked powers of observation, or did not use their powers or failed to appreciate the value of such powers, is simply a display of ignorance of what they actually did.

On the other hand, when it comes to the question of the principles of experimental science and the value they placed on them, these men of the medieval universities, when sympathetically studied, prove to have been quite as sensible as the scientists of our own time. The idea that Francis Bacon in any way laid the foundation of the experimental sciences, or indeed did anything more than give a literary statement of the philosophy of the experimental science, though he himself proved utterly unable to apply the principles that he discussed to the scientific discoveries of his own time, is one of the inexplicable absurdities of history that somehow get in and {301} cannot be got out. The great thinkers of the medieval period had not only reached the same conclusions as he did, but actually applied them three centuries before; and the great medieval universities were occupied with problems, even in physical science, not very different from those which have given food for thought for subsequent generations. We shall see in the next chapter how successfully they applied these great principles of the experimental method, and how much they antic.i.p.ated many phases of science that we are apt to think of as distinctly modern.

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CHURCHMEN AND PHYSICAL SCIENCE AT THE MEDIEVAL UNIVERSITIES.

There can be no doubt at all in the minds of those who know anything about the early history of the universities, but that the Popes were entirely favorable to the great educational movement represented by these inst.i.tutions. It is ordinarily supposed, however, that the medieval universities limited their attention to philosophy and theology, and that even these subjects were studied from such narrow religious standpoints, as to make them of very little value for the development of human knowledge or the evolution of the human mind. Any such supposition is the result of ignorance on the part of those who entertain it, as to the actual curriculum of studies at the early universities, though it is not surprising that it should be very common, because, unfortunately, it has been fostered by many writers on educational subjects, especially in English. Scholasticism is often said to have been the very acme of absurdity in teaching, and its real import is entirely missed. Students and professors are supposed to have been limited in their interests to dialectics and metaphysics in the narrowest sense of these terms, and much time was, according to even presumably good authorities, frittered away in idle speculations with regard to things that are absolutely unknowable. [Footnote 36]

[Footnote 36: Much of the remainder of this chapter is taken from the chapter on What and How They Studied at the Universities, in my book The Thirteenth Greatest of Centuries. (Catholic Summer School Press, N. Y.) Some of the sources from which the material is obtained will be found more fully referred to there, and further information with regard to scientific studies at these universities will be found in the chapter on Post-graduate Work in the same book, from which a certain amount of material is used again here.]

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Anyone who studies the works of the professors at these medieval universities can scarcely fail to become entirely sympathetic toward these scholars, who devoted themselves with so much ardor to every form of learning that interested them, and who did not fail to accomplish at least as much for future generations, as any other generation of university men in history. Professor George Saintsbury in his book On the Rise of Romance and the Flourishing of Allegory, which is really the story of thirteenth century literature in Europe, in the series of Periods of European Literature, [Footnote 37] in summing up the contributions of these medieval professors to human knowledge, said:

[Footnote 37: Scribners, 1896.]

"Yet, there has always, in generous souls who have some tincture of philosophy, subsisted a curious kind of sympathy and yearning over the work of these generations of mainly disinterested scholars, who, whatever they were, were thorough, and whatever they could not do, could think. And there have been in these latter days some graceless ones who have asked whether the science of the nineteenth century, after an equal interval, will be of any more positive value--whether it will not have even less comparative interest than that which appertains to the Scholasticism of the thirteenth."

Nothing could well be less true than the impression that philosophy and theology were the exclusive subjects of the medieval university curriculum. If because our modern universities devote a great amount of time to physical science in its various forms, and more of their publications concern this department of educational work than any other, it were to be said by some future generation that our universities occupied themselves {304} with nothing but physical science, it would be much more true than the expressions which stamp medieval university teaching as limited to dialectics and metaphysics.

Besides science in the modern universities, philosophy in all its branches is the subject of ardent devotion, and the cla.s.sics and languages are not neglected, and medicine and law are important post-graduate departments, and even theology comes in for a goodly share of attention and occupies the minds of many deep students. In the medieval universities, medicine particularly occupied a very large share of attention; but all the physical sciences were the subject not only of distant curiosity, but of careful investigation, many of them along lines that are supposed to be distinctly modern, yet which are really as old as the university movement.

Turner in his History of Philosophy [Footnote 38] summed up the books most commonly used, the method of examination and of conferring degrees, in a way that shows the character of university teaching during the thirteenth century, and brings out not only its thoroughness, but also the fact that a good deal of time was devoted to what we now call physical or natural science, since the treatises on animals, on the earth and on meteors, under which all the phenomena of the Heavens were included, represent almost exactly those questions in physical science that most men who do not intend to devote themselves particularly to science care to know something about at the present time. He says:

[Footnote 38: Ginn & Co., Boston and New York, 1903.]

"By statutes issued at various times during the thirteenth century, it was provided that the professor should read, that is, expound, the text of certain standard {305} authors in philosophy and theology. In a doc.u.ment published by Denifle (the distinguished authority on medieval universities), and by him referred to the year 1252, we find the following works among those prescribed for the Faculty of Arts: Logica Vetus (the old Boethian text of a portion of the Organon, probably accompanied by Porphyry's Isagoge); Logica Nova (the new translation of the Organon); Gilbert's Liber s.e.x Principiorum; and Donatus's Barbarismus. A few years later (1255), the following works are prescribed: Aristotle's Physics, Metaphysics, De Anima, De Animalibus, De Caelo et Mundo, Meteorica, the minor psychological treatises and some Arabian or Jewish works, such as the Liber de Causis and De Differentia Spiritus et Animae."

As time went on in the thirteenth and fourteenth centuries, the attention to physical sciences was increased rather than diminished.

Much of Albertus Magnus's work, and practically all of that of Aquinas and Roger Bacon, was done after the date here given (1255).

The medieval workers at the universities were under the obligation of having to lay the foundations for modern thought, instead of being able to build up the magnificent superstructure which has risen in the seven centuries since the universities were founded. Without the foundation, however, the building would indeed not be worthy of admiration. Their work is concealed beneath the surfaces of things, but is not the less important for that, and is in most ways more significant than many portions of the structure that have risen above it. Unless one digs down to see how broad and deep and firm they laid the foundations, the modern critic will not be able to appreciate their work at its true value. Very few men are able to do this; still fewer have the time or the inclination. The consequence is a sad lack of sympathy with these old-time workers, who nevertheless did their work so well, and whose accomplishment meant so much for the modern time. It is not hard to {306} show that their minds were occupied with just the same problems that interest us, and the wonderful thing is that they antic.i.p.ated so many of our conclusions, though these antic.i.p.ations are wrapped up not infrequently in a terminology that obscures their meaning for any but the patient, sympathetic student.

In his Harveian Lecture, Science and Medieval Thought, Professor Clifford Allb.u.t.t, of the University of Cambridge, England, said:--

"Each period of human achievement has its phases of spring, culmination, and decline; and it is in its decline that the leafless tree comes to judgment. In the unloveliness of decay, the Middle Ages are as other ages have been; as our own will be; but in those ages there was more than one outburst of life; more than once the enthusiasm of the youth of the West went out to explore the ways of the realm of ideas; and if we believe ourselves at last to have found the only thoroughfare, we owe this knowledge to those who before us traveled the uncharted seas. If we have inherited a great commerce and dominion of science, it is because their argosies had been on the ocean and their camels on the desert. _Discipulus est prioris posterior dies;_ man cannot know all at once; knowledge must be built up by laborious generations. In all times, as in our own, the advance of knowledge is very largely by elimination and negation; we ascertain what is not true, and we weed it out. To perceive and respect the limits of the knowable, we must have sought to transgress them. We can build our bridge over the chasm of ignorance with stored material in which the thirteenth century was poor indeed; we can fix our bearings where then was no foundation; yet man may be well engaged when he knows not the ends of his work; and the schoolmen in digging for treasure cultivated the field of knowledge, even for Galileo and Harvey, for Newton and Darwin. Their many errors came not of indolence, for they were pa.s.sionate workers; not of hatred of light, for they were eager for the light; not of fickleness, for they wrought with unparalleled devotion; nor indeed of ignorance of particular things, {307} for they knew many things.

They erred because they did not know, and they could not know the conditions of the problems which, as they emerged from the cauldron of war and from the wreck of letters and science, they were nevertheless bound to attack, if civil societies worthy of the name were to be constructed."

We are very p.r.o.ne to think that the interests of the men of the Middle Ages were very different to our own, and that they had not the slightest inkling of what were to be the interests of the future centuries. Ordinarily students of science, for instance, would be sure to think that electricity and magnetism, interest in which is supposed to be a thing of comparatively recent years, or at most of the last two centuries, would not be mentioned at all in the thirteenth century. Such an idea is not only absolutely false to the history of science as we know it, but is utterly unjust to the powers of observation of men who have always noted, and almost necessarily tried to investigate, the phenomena which are now grouped under these sciences. Perhaps no better idea of the intense interest of this first century of university life in natural phenomena can be obtained, than will be gleaned at once from the following short paragraph, in which Brother Potamian, of Manhattan College, in his brief, striking introduction to the letter of Petrus Peregrinus describing the first conception of a dynamo, condenses the references to magnetic manifestions that are found in the literature of the time. [Footnote 39]

[Footnote 39: The Letter of Petrus Peregrinus, N. Y., 1904.]

Most of the writers he mentions were not scientists in the ordinary sense of the word, but were literary men; and the fact that these references occur, shows very clearly that there must have been widespread interest in such scientific phenomena, since they had attracted the {308} attention of literary writers, who would not have spoken of them doubtless, but that they knew that in this they would be satisfying as well as exciting public interest.

"Abbot Neckam, the Augustinian (1157-1217), distinguished between the properties of the two ends of the lodestone, and gives in his De Utensilibus what is perhaps the earliest reference to the mariner's compa.s.s that we have. Albertus Magnus, the Dominican (1193-1230), in his treatise De Mineralibus, enumerates different kinds of natural magnets and states some of the properties commonly attributed to them; the minstrel, Guyot de Provins, in a famous satirical poem written about 1208, refers to the directive quality of the lodestone and its use in navigation, as do also Cardinal de Vitry in his Historia Orientalis (1215-1220); Brunetto Latini, poet, orator and philosopher (the teacher of Dante), in his Tresor des Sciences, a veritable library, written in Paris in 1260; Raymond Lully, the enlightened Doctor, in his treatise, De Contemplatione, begun in 1272; and Guido Guinicelli, the poet-priest of Bologna, who died in 1276."

All of these writers, it may be said, with a single exception, were clergymen, and some of them were very prominent ecclesiastics in their time.

The present generation has not as yet quite got over the bad habit of making fun of these medieval thinkers for having accepted the idea of the trans.m.u.tation of metals and searched so a.s.siduously for the philosopher's stone. This supposed absurdity has for most scientific minds during the nineteenth century been quite enough of itself, without more ado, to stamp the generations of the Middle Ages who accepted it, as utterly lacking, if not in common sense, at least in serious reasoning power. At the present moment, however, we are in the full tide of a set of opinions that tend to make us believe not {309} only in the possibility, but in the actual occurrence of the trans.m.u.tation of metals. Observations made with regard to radium have revolutionized all the scientific thinking in this matter. Radium has apparently been demonstrated changing into helium, and so there is a trans.m.u.tation of metals. On the strength of this and certain other recently investigated physical phenomena, there is a definite tendency in the minds of many serious students of physics and chemistry to consider that other metals possibly change into one another, and that all that is needed is careful observation to discover it, for this change is supposed to be going on around us all the time. Not very long since, a professor of physical science at an important American university suggested that it would be extremely interesting to take a large specimen of lead ore, say several tons, and having removed from it carefully all traces of silver that might be contained in it, put it away for twenty years, and then see whether any further traces of silver could be found. The idea that possibly lead occasionally changes into silver by some slow chemical process is evidently deep-seated in his mind. It would remind one of Newton's expression some two centuries ago, that he had seen copper and gold ores occurring together in specimens, and that he looked upon this as evidence that copper in the course of time changes into gold. Certain it is that lead ores constantly occur in connection with silver, or at least that silver is found wherever lead is; that a corresponding relationship between gold and copper has also been noted; and that Newton's idea was not near so absurd, in the light of what we now know, or still more, what we surmise on good scientific grounds, as the nineteenth century scientists would have had us believe.

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As I go over this ma.n.u.script for the last time just before going to press, there comes the announcement that Sir William Ramsay has probably solved the problem of the trans.m.u.tation of metals. He has shown apparently that lithium, when acted upon by radium emanations, changes to some extent to copper. It is true that the change is only in small quant.i.ties, and that there is no question as yet of any commercial value to the process; but we all know that it is by such small scientific announcements as this that the entering wedges of large industrial processes are introduced. The fact that this announcement should have been made before the British a.s.sociation for the Advancement of Science and by a thoroughly conservative English chemist, probably settles forever the question of the trans.m.u.tation of metals, in the way that the people of the Middle Ages looked at the problem rather than as the intervening centuries did.

The old medieval thinkers, then, were only ridiculous to a few generations of nineteenth century scientists who, because they knew a little more about certain details in science than preceding generations had done, thought that they knew all that there was to be known about this immense subject, and made fun of thinkers quite as great as themselves in preceding centuries. At the beginning of the twentieth century, instead of making ourselves ludicrous by raising a laugh at the expense of these fellow students in science of the olden time, we should rather feel like congratulating them upon the perspicacity which enabled them to antic.i.p.ate a great truth with regard to the relationships of chemical elements, especially the metals, to each other. The present-day idea of thinking physicists and chemists is {311} that the seventy odd elements described in our textbooks on chemistry, are not so many essentially independent forms of matter, but are rather examples of one kind of material exhibiting special dynamic energies which it possesses under varying conditions, as yet not well understood. This was exactly the idea that the old scholastic philosophers had of the const.i.tution of matter. They said that matter was composed of two principles, prime matter and form.

When this doctrine of theirs is properly elucidated, it proves to be an antic.i.p.ation of what is most modern in the thoughts of twentieth century physicists. A re-statement of the old-time views would read not unlike many a contribution to a discussion of this subject at an annual meeting of the British or American a.s.sociations for the Advancement of Science.

This doctrine of prime matter and form, which the scholastics adopted and adapted from the Greeks, and especially from Aristotle, cannot fail to be of interest even to modern scientists. According to it, prime matter was an indeterminate something which made up the underlying substratum of all material things. Form was the dynamic element which entered into the composition of matter and made it exhibit its specific qualities. We have heard much of ionization in recent times, and in many ways this would remind one even only slightly familiar with the old scholastics, of their theories of form entering into matter. Prime matter was supposed to be absolutely without distinguishing characteristics of its own. It was indifferent, and had no influence on other material unless when a.s.sociated with form. Form was the dynamic and energizing element.

This, of course, still remains in the realm of theory; {312} but it is interesting to realize that in the olden time they theorized about the const.i.tution of matter at the universities of the thirteenth and fourteenth centuries just as we do now, and most surprisingly came to conclusions quite like ours. Their thoughts not only concerned the same subject, but were worked out in the same way. It is idle to say that they knew nothing about it and hit on their theory by chance. As a matter of fact, they knew very little, if any less about it than we do, for our ignorance on this subject is monumental, and they antic.i.p.ated our latest thinking by seven centuries. Many have been the divagations of thought since that time, but now we return to their conclusions. It is chastening to the modern mind, so confident of the advances that have been made by these latter generations, "the heirs of all the ages in the foremost files of time," to find that we are so little farther on in an important problem than these men of the thirteenth century.

Other basic problems with regard to matter and force filled the minds of the medieval schoolmen quite as they do those of the modern generations. For instance, they occupied themselves with the question of the indestructibility of matter, and also, strange as it may seem, with the conservation of energy. We have presumably learned so much by experimental demonstration and original observation in the physical sciences in the modern times, and especially during the precious nineteenth century, that any thinking of the medieval mind along these lines might, in the opinion of those who know nothing of what they speak, be at once set aside without further question as preposterous, or at best nugatory. The opinions of medieval scholars in these matters would be presumed, without more ado, to have been so entirely {313} speculative as to deserve no further attention. Nothing could well be farther from the truth than this. Nowhere will more marvelous antic.i.p.ations of what is most modern in science be found than in some of these considerations of basic principles in the physical sciences.

For instance, Thomas Aquinas, usually known as St. Thomas, in a series of lectures given at the University of Paris toward the end of the third quarter of the thirteenth century, stated as the most important conclusion with regard to matter that _"Nihil omnino in nihilum redigetur._--Nothing at all will ever be reduced to nothingness." By this, as is very evident from the context, he meant to say that matter would never be annihilated and could never be destroyed. It might be changed in various ways, but it could never go back into the nothingness from which it had been taken by the creative act.

Annihilation was p.r.o.nounced as not being a part of the scheme of things as far as the human mind could hope to fathom its meaning.

In this sentence, then, Thomas of Aquin was proclaiming the doctrine of the indestructibility of matter. It was not until well on in the nineteenth century that the chemists and physicists of modern times realized the truth of this great principle. The chemists had seen matter change its form in many ways, had seen it disappear apparently in the smoke of fire or evaporate under the influence of heat, but investigation proved that if care were taken in the collection of the gases that came off under these circ.u.mstances, of the ashes of combustion and of the residue of evaporation, all the original material that had been contained in the supposedly disappearing substance could be recovered, or at least {314} completely accounted for. The physicists on their part had realized this same truth, and finally there came the definite enunciation of the absolute indestructibility of matter. St. Thomas's conclusion, "Nothing at all will ever be reduced to nothingness," had antic.i.p.ated this doctrine by nearly seven centuries. What happened in the nineteenth century was that there came an experimental demonstration of the truth of the principle. The principle itself, however, had been reached long before by the human mind, by speculative processes quite as inerrable in their way as the more modern method of investigation.

When St. Thomas used the aphorism, "Nothing at all will ever be reduced to nothingness," there was another signification that he attached to the words quite as clearly as that by which they expressed the indestructibility of matter. For him _nihil_ or nothing meant neither matter nor form, that is, neither the material substance nor the energy which is contained in it. He meant, then, that no energy would ever be destroyed as well as no matter would ever be annihilated. He was teaching the conservation of energy as well as the indestructibility of matter. Here once more the experimental demonstration of the doctrine was delayed for over six centuries and a half. The truth itself, however, had been reached by this medieval master-mind, and was the subject of his teaching to the university students in Paris in the thirteenth century. These examples should, I think, serve to ill.u.s.trate that the minds of medieval students were occupied with practically the same questions as those which are now taught to the university students of our day, and that the content of the teaching was identical with ours.

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The scholars of the Middle Ages are usually said to have been profoundly ignorant as regards the shape of the earth, its size, and the number of its inhabitants, and to have cherished the queerest notions, when they really permitted themselves any ideas at all, as to the antipodes. This is very true if the ideas of the ignorant ma.s.ses of the people and the second-rate authors and thinkers be taken as the standard of medieval thought. Unfortunately, such sources as these have only too often served as authorities for modern historians of education and modern essayists on the history of science. This state of affairs would painfully suggest the curiously inverted notion of the supposed ideas entertained with regard to science in our day, that would be obtained by some thirtieth century student, were he to judge our scientific opinions from some of the queer books written by pretentiously ignorant writers, who have pet scientific hobbies of their own and exploit them at the expense of a long-suffering world, if by some accident of fortune these books should be preserved and the really great contributions to science be either actually lost or lost to sight. It is from Albert the Great and such men, and not from their petty contemporaries, that the true spirit of the science of the age must be deduced. Albert's biographer said:

"He treats as fabulous the commonly-received idea, in which Venerable Bede had acquiesced, that the region of the earth south of the equator was uninhabitable, and considers, that from the equator to the South Pole, the earth was not only habitable, but in all probability actually inhabited, except directly at the poles, where he imagines the cold to be excessive. If there be any animals there, he says, they must have very thick skins to defend them from the rigor of the climate, and they are probably of a white color. The intensity of cold is, {316} however, tempered by the action of the sea. He describes the antipodes and the countries they comprise, and divides the climate of the earth into seven zones. He smiles with a scholar's freedom at the simplicity of those who suppose that persons living at the opposite region of the earth must fall off, an opinion that can only rise out of the grossest ignorance, _'for when we speak of the lower hemisphere, this must be understood merely as relatively to ourselves.'_

"It is as a geographer that Albert's superiority to the writers of his own time chiefly appears. Bearing in mind the astonishing ignorance which then prevailed on this subject, it is truly admirable to find him correctly tracing the chief mountain chains of Europe, with the rivers which take their source in each; remarking on portions of coast which have in later times been submerged by the ocean, and islands which have been raised by volcanic action above the level of the sea; noticing the modification of climate caused by mountains, seas and forests, and the division of the human race, whose differences he ascribes to the effect upon them of the countries they inhabit. In speaking of the British Isles, he alludes to the commonly-received idea that another distant island called Thile, or Thule, existed far in the Western Ocean, uninhabitable by reason of its frightful climate, but which, he says, has perhaps not yet been visited by man."

In only needs to be said in addition to this, that Albert had more than a vague hint of the possible existence of land on the other side of the globe. He gives an elaborate demonstration of the sphericity of the earth, and it has been suggested by more than one scholar that his views on this subject led eventually to the discovery of America.

Humboldt, the distinguished German natural philosopher of the beginning of the nineteenth century, who was undoubtedly the most important figure in scientific thought in his own time, and whose own work was great enough to have an enduring influence even down to our {317} day, in spite of the immense progress made during the nineteenth century, has praised Albert's work very highly. Almost needless to say, Humboldt was possessed of a thorough critical faculty and had a very wide range of knowledge, so that he was in an eminently proper position to judge of Albert's work. He has summed up his appreciation briefly as follows:

"Albertus Magnus was 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 incidence of the sun's rays in heating the ground, _which have excited my surprise._"

I have thought that perhaps the best way to bring out properly Albert's knowledge in the physical sciences would be to take up Humboldt's headings in their order and ill.u.s.trate them by quotations from the great scholar's writings--the only scholar to whom the epithet has been applied in all history--and from condensed accounts as they appear in his life written by Sighart. [Footnote 40] These will serve to show at once the extent of Albert's knowledge and the presumptuous ignorance of those who make little of the science of the medieval period.