The same freedom, which every one was to have as to the general standpoint, was intended also for all with regard to the arrangement and limitation of the topic. All the sectional addresses were supposed to deal either with relations or with fundamental problems of to-day. It would have been absurd to demand that in every case the totality of relations or of problems should be covered or even touched. The result would have become perfunctory and insignificant. No one intended to produce a cyclopedia. It was essential everywhere to select that which was most characteristic of the tendencies of the age and most promising for the science of the twentieth century. Those problems were to be emphasized whose solution is most demanded for the immediate progress of knowledge, and those relations had to be selected through which new connections, new synthetic thoughts prepare themselves to-day. That this selection had to be left to the speaker was a matter of course.

Yet it may be said that in all these directions, with reference to the general standpoint and with reference to problems and relations, the Organizing Committee had somewhat prepared the choice through the selection of the speakers themselves. As the standpoints of the leading speakers were well known, it was not difficult to invite as far as possible for every place a scholar whose general views would be least out of harmony with the principles of the plan. For instance, when we had the task before us of selecting the divisional speakers for the Normative and for the Mental Sciences, it was only natural to invite for the first a philosopher of idealistic type and for the latter a philosopher of positivistic stamp, inasmuch as the whole scheme gave to the mental sciences the same place which they would have had in a positivistic scheme, while the normative sciences would have lost the meaning which they had in our plan if a positivist had simply psychologized them. In the same way we gave preference as far as possible, for the addresses on relations, to those scholars whose previous work was concerned with new synthetic movements, and as speakers on problems those were invited who were in any case engaged in the solution of those problems which seemed central in the present state of science. Thus it was that on the whole the expectation was justified that the most characteristic relations and the most characteristic problems would be selected if every invited speaker spoke essentially on those relations and on those problems with which his own special work was engaged.

Yet there is no doubt that this expectation was sometimes fulfilled beyond our antic.i.p.ation, in an amount of specialization which was no longer entirely in harmony with the general character of the undertaking. The general problem has become sometimes only the starting-point or almost the pretext for speaking on some relation or problem so detailed that it can hardly stand as a representative symbol of the whole movement in that sectional field. Especially in the practical sciences more room was sometimes taken for particular hobbies and chance aspects than in the eyes of the originators the occasion may have called for. Yet on the whole this was the exception. The overwhelming majority of the addresses fulfilled n.o.bly the high hopes of the Boards, and even in those exceptional cases where the speaker went his own way, it was usually such an original and stimulating expression of a strong personality that no one would care to miss this tone in the symphony of science.

Even now of course, though the Congress days have pa.s.sed, and only typewritten ma.n.u.scripts are left from all those September meetings, it would be easy to provide, by editorial efforts, for a greater uniformity and a smoother harmonization. Most of the authors would have been quite willing to retouch their addresses in the interest of greater objective uniformity and to accept the hint of an editorial committee in elaborating more fully some points and in condensing or eliminating others. Much was written in the desire to bring a certain thought for discussion before such an eminent audience, while the speaker would be ready to subst.i.tute other features of the subject for the permanent form of the printed volume. Yet such editorial supervision and transformation would be not only immodest but dangerous. We might risk gaining some external uniformity, but only to lose much of the freshness and immediacy and brilliancy of the first presentation. And who would dare to play the critical judge when the international contributors are the leaders of thought? There was therefore not the slightest effort made to suggest revision of the ma.n.u.scripts, for which the whole responsibility must thus fall to the particular author. The reduction to a uniform language seemed, on the other hand, most natural, and those who had delivered their addresses in French, German, or Italian themselves welcomed the idea that their papers should be translated into English by competent specialists. The short bibliographies, selected mostly through the chairman of the departments, and the very full index with references may add to the general usefulness of the eight volumes in which the work is to be presented.

But the significance of the Congress of Arts and Science ought not to be measured and valued only by reference to this printed result. Its less visible side-effects seem in no way less important for scholarship, and they are fourfold. There was, first, the personal contact between the scholarly public and the leaders of thought; there was, secondly, the first academic alliance between the United States and Europe; there was, thirdly, the first demonstration of a world congress crystallized about one problem; there was, fourthly, the unique accentuation of the thought of unity in all human science; and each of these four movements will be continued and reinforced by the publication of these proceedings.

The first of these four features, the contact of the scholarly public with the best thinkers of our time, had, to be sure, its limitations. It was not sought to create a really popular congress. Neither the level of the addresses, nor the size of the halls, nor the number of invitations sent out, nor the general conditions of a world"s fair at which the expense of living is high and the distractions thousandfold, favored the attendance of crowds. It was planned from the first that on the whole scholars and specialists should attend and that the army should be made up essentially of officers. If in an astronomical section perhaps thirty men were present, among whom practically every one was among the best known directors of observatories or professors of mathematics, astronomy, or physics, from all countries of the globe, much more was gained than if three thousand had been in the audience, brought together by an interest of curiosity in moon and stars. For the most part there must have been between a hundred and two hundred in each of the 128 sectional meetings, and that was more than the organizers expected. This direct influence on the interested public is now to be expanded a thousandfold by the mission work of these volumes. The concentration of these hundreds of addresses into a few days made it in any case impossible to listen to more than to a small fraction; these volumes will bring at last all speakers to coordinated effectiveness; and while one hall suffered from bad acoustics, another from bad ventilation, and a third from the pa.s.sing of the intermural trains, here at least is an audience in which nothing will disturb the sensitive nerves of the willing follower.

But much more emphasis is due to the second feature. The Congress was an epoch-making event for the international world of scholarship from the fact that it was the first great undertaking in which the Old and the New Worlds stood on equal levels and in which Europe really became acquainted with the scientific life of these United States. The contact of scholarship between America and Europe has, indeed, grown in importance through many decades. Many American students had studied in European and especially in German universities and had come back to fill the professorial chairs of the leading academic inst.i.tutions. The spirit of the Graduate School and the work towards the Doctor"s degree, yes, the whole productive scholarship of recent decades had been influenced by European ideals, and the results were no longer ignored at the seats of learning throughout the whole world. European scholars had here and there come as visiting lecturers or as a.s.similated instructors, and a few American scholars belonged to the leading European Academies. Yet, whoever knew the real development of American post-graduate university life, the rapid advance of genuine American scholarship, the incomparable progress of the scientific inst.i.tutions of the New World, of their libraries and laboratories, museums and a.s.sociations, was well aware that Europe had hardly noticed and certainly not fully understood the gigantic strides of the country which seemed a rival only on commercial and industrial ground. Europe was satisfied with the traditional ideas of America"s scientific standing which reflected the situation of thirty years ago, and did not understand that the changes of a few l.u.s.tres mean in the New World more than under the firmer traditions of Europe. American scientific literature was still neglected; American universities treated in a condescending and patronizing spirit and with hardly any awareness of the fundamental differences in the inst.i.tutions of the two sides. Those European scholars who crossed the ocean did it with missionary, or perhaps with less unselfish, intentions, and the Americans who attended European congresses were mostly treated with the friendliness which the self-satisfied teacher shows to a promising pupil. The time had really come when the contrast between the real situation and the traditional construction became a danger for the scientific life of the time. Both sides had to suffer from it. The Americans felt that their serious and important achievements did not come to their fullest effectiveness through the insistent neglect of those who by the tradition of centuries had become the habitual guardians of scientific thought. A kind of feeling of dependency as it usually develops in weak colonies too often depressed the conscientious scholarship on American soil as the result of this undue condescension. Yet the greater harm was to the other side.

Once before Europe had had the experience of surprise when American successes presented themselves where nothing of that kind was antic.i.p.ated in the Old World. It was in the field of economic life that Europe looked down patronizingly on America"s industrial efforts, and yet before she was fully aware how the change resulted, suddenly the warning signal of the "American danger" was heard everywhere. The surprise in the intellectual field will not be less. The unpreparedness was certainly the same. Of course, there cannot be any danger of rivalry in the scientific field, inasmuch as science knows no compet.i.tion but only cooperation. And yet it cannot be without danger for European science if it willfully neglects and recklessly ignores this eager working of the modern America. For both sides a change in the situation was thus not only desirable, but necessary; and to prepare this change, to subst.i.tute knowledge for ignorance, nothing could have been more effective than this Congress of Arts and Science.

Even if we abstract from the not inconsiderable number of those European scholars who followed naturally in the path of the invited guests, and if we consider merely the function of these invited partic.i.p.ants, the importance of the procedure is evident. More than a hundred leading scholars from all European countries came under conditions where academic fellowship on an equal footing was a necessary part of the work. There was not the slightest premium held out which might have attracted them had not real inter-academic interest brought them over the ocean, and no missionary spirit was appealed to, as everything was equally divided between American and foreign contributors. It was a real feast of international scholarship, in which the importance and the number of foreigners stamped it as the first significant alliance of the spirit of learning in the New and the Old Worlds. And it was essentially for this purpose that the week of personal intermingling in St. Louis itself was preceded and followed by happy weeks of visits to leading universities. Almost every one of those one hundred European scholars visited Harvard and Yale, Chicago and Johns Hopkins, Columbia and Pennsylvania, saw the treasures of Washington and examined the exhibitions of American scholarship in the World"s Fair itself. The change of opinion, the disappearance of prejudice, the growth of confidence, the personal intercollegiate ties which resulted from all that, have been evident since those days all over Europe. And it is not surprising that it is just the most famous and most important of the visitors, famous and important through their width and depth of view, whose expression of appreciation and admiration for the new achievements has been loudest.

We insisted that the effectiveness of the Congress showed itself in two other directions still: on the one side, there was at last a congress with a unified programme, a congress which stood for a definite thought, and which brought all its efforts to bear on the solution of one problem. There seemed a far-reaching agreement of opinion that this new principle of congress administration had successfully withstood the test of practical realization. Mere conglomerations of unconnected meetings with casual programmes and unrelated papers cannot claim any longer to represent the only possible form of international gatherings of scholars. More than that, their superfluous and disheartening character will be felt in future more strongly than before. No congress will appear fully justified whose printed proceedings do not show a real plan in its programme. And the consciousness of this mission of the Congress will certainly be again reinforced by the publication of these volumes, inasmuch as it is evident that they represent a substantial contribution to the knowledge of our time which would not have been made without the special stimulating occasion of the Congress.

And, finally, whether such a congress is held again or not, the impulse of this one cannot be lost on account of the special end to which all its efforts have been directed: the unity of scientific knowledge. We had emphasized from the first that here was the centre of our purposes in a time whose scientific specialization necessarily involves a scattering of scholarly work and which yet in its deepest meaning strives for a new synthesis, for a new unity, which is to give to all this scattered labor a real dignity and significance; truly nothing was more needed than an intense accentuation of the internal harmony of all human knowledge. But for that it is not enough that the ma.s.ses feel instinctively the deep need of such unifying movements, nor is it enough that the philosophers point with logical arguments towards the new synthesis. The philosopher can only stand by and point the way; the specialists themselves must go the way. And here at last they have done so. Leaders of thought have interrupted their specialistic work and have left their detailed inquiries to seek the fundamental conceptions and methods and principles which bind all knowledge together, and thus to work towards that unity from which all special work derives its meaning.

Whether or not their cooperation has produced anything which is final is a question almost insignificant compared with the fundamental fact that they cooperated at all for this ideal synthetic purpose. This fact can never lose its influence on the scholarly effort of our age, and will certainly find its strongest reinforcement in this unified publication.

It has fulfilled its n.o.blest purpose if it adds strength to the deepest movement of our time, the movement towards unity of meaning in the scattered manifoldness of scientific endeavor with which the twentieth century has opened.

[Ill.u.s.tration: _Simon Newcomb, Ph.D., LL.D._

Dr. Newcomb, the famous Astronomer, is conceded to be the Dean of American scientists. His eminent services to the Government of the United States, and his recognized position in foreign and domestic scientific circles, made him peculiarly fitted to deliver the introductory address, and to officiate as President of an International Congress of the leading scientists of the world.

He has been the recipient of honorary degrees from six American and ten European Universities, and he is a member of almost every important Academy of Science in Europe and America. He is an officer of the Legion of Honour, and is the only native American besides Benjamin Franklin who has been elected an a.s.sociate of the Inst.i.tute de France. From 1861 to 1897 he was Professor of Mathematics in the United States Navy. He also lectured on Mathematics and Astronomy at Johns Hopkins, and is now a Professor Emeritus in the Faculty of Arts of that university. Dr.

Newcomb is the author of numerous works on Astronomy and other scientific subjects.]

PROCEEDINGS OF THE CONGRESS

INTRODUCTORY ADDRESS

DELIVERED AT THE OPENING EXERCISES AT FESTIVAL HALL BY PROFESSOR SIMON NEWCOMB, PRESIDENT OF THE CONGRESS

THE EVOLUTION OF THE SCIENTIFIC INVESTIGATOR

As we look at the a.s.semblage gathered in this hall, comprising so many names of widest renown in every branch of learning,--we might almost say in every field of human endeavor,--the first inquiry suggested must be after the object of our meeting. The answer is, that our purpose corresponds to the eminence of the a.s.semblage. We aim at nothing less than a survey of the realm of knowledge, as comprehensive as is permitted by the limitations of time and s.p.a.ce. The organizers of our Congress have honored me with the charge of presenting such preliminary view of its field as may make clear the spirit of our undertaking.

Certain tendencies characteristic of the science of our day clearly suggest the direction of our thoughts most appropriate to the occasion.

Among the strongest of these is one toward laying greater stress on questions of the beginning of things, and regarding a knowledge of the laws of development of any object of study as necessary to the understanding of its present form. It may be conceded that the principle here involved is as applicable in the broad field before us as in a special research into the properties of the minutest organism. It therefore seems meet that we should begin by inquiring what agency has brought about the remarkable development of science to which the world of to-day bears witness. This view is recognized in the plan of our proceedings, by providing for each great department of knowledge a review of its progress during the century that has elapsed since the great event commemorated by the scenes outside this hall. But such reviews do not make up that general survey of science at large which is necessary to the development of our theme, and which must include the action of causes that had their origin long before our time. The movement which culminated in making the nineteenth century ever memorable in history is the outcome of a long series of causes, acting through many centuries, which are worthy of especial attention on such an occasion as this. In setting them forth we should avoid laying stress on those visible manifestations which, striking the eye of every beholder, are in no danger of being overlooked, and search rather for those agencies whose activities underlie the whole visible scene, but which are liable to be blotted out of sight by the very brilliancy of the results to which they have given rise. It is easy to draw attention to the wonderful qualities of the oak; but from that very fact, it may be needful to point out that the real wonder lies concealed in the acorn from which it grew.

Our inquiry into the logical order of the causes which have made our civilization what it is to-day will be facilitated by bringing to mind certain elementary considerations--ideas so familiar that setting them forth may seem like citing a body of truisms--and yet so frequently overlooked, not only individually, but in their relation to each other, that the conclusion to which they lead may be lost to sight. One of these propositions is that psychical rather than material causes are those which we should regard as fundamental in directing the development of the social organism. The human intellect is the really active agent in every branch of endeavor,--the _primum mobile_ of civilization,--and all those material manifestations to which our attention is so often directed are to be regarded as secondary to this first agency. If it be true that "in the world is nothing great but man; in man is nothing great but mind," then should the keynote of our discourse be the recognition of this first and greatest of powers.

Another well-known fact is that those applications of the forces of nature to the promotion of human welfare which have made our age what it is, are of such comparatively recent origin that we need go back only a single century to antedate their most important features, and scarcely more than four centuries to find their beginning. It follows that the subject of our inquiry should be the commencement, not many centuries ago, of a certain new form of intellectual activity.

Having gained this point of view, our next inquiry will be into the nature of that activity, and its relation to the stages of progress which preceded and followed its beginning. The superficial observer, who sees the oak but forgets the acorn, might tell us that the special qualities which have brought out such great results are expert scientific knowledge and rare ingenuity, directed to the application of the powers of steam and electricity. From this point of view the great inventors and the great captains of industry were the first agents in bringing about the modern era. But the more careful inquirer will see that the work of these men was possible only through a knowledge of the laws of nature, which had been gained by men whose work took precedence of theirs in logical order, and that success in invention has been measured by completeness in such knowledge. While giving all due honor to the great inventors, let us remember that the first place is that of the great investigators, whose forceful intellects opened the way to secrets previously hidden from men. Let it be an honor and not a reproach to these men, that they were not actuated by the love of gain, and did not keep utilitarian ends in view in the pursuit of their researches. If it seems that in neglecting such ends they were leaving undone the most important part of their work, let us remember that nature turns a forbidding face to those who pay her court with the hope of gain, and is responsive only to those suitors whose love for her is pure and undefiled. Not only is the special genius required in the investigator not that generally best adapted to applying the discoveries which he makes, but the result of his having sordid ends in view would be to narrow the field of his efforts, and exercise a depressing effect upon his activities. The true man of science has no such expression in his vocabulary as "useful knowledge." His domain is as wide as nature itself, and he best fulfills his mission when he leaves to others the task of applying the knowledge he gives to the world.

We have here the explanation of the well-known fact that the functions of the investigator of the laws of nature, and of the inventor who applies these laws to utilitarian purposes, are rarely united in the same person. If the one conspicuous exception which the past century presents to this rule is not unique, we should probably have to go back to Watt to find another.

From this viewpoint it is clear that the primary agent in the movement which has elevated man to the masterful position he now occupies, is the scientific investigator. He it is whose work has deprived plague and pestilence of their terrors, alleviated human suffering, girdled the earth with the electric wire, bound the continent with the iron way, and made neighbors of the most distant nations. As the first agent which has made possible this meeting of his representatives, let his evolution be this day our worthy theme. As we follow the evolution of an organism by studying the stages of its growth, so we have to show how the work of the scientific investigator is related to the ineffectual efforts of his predecessors.

In our time we think of the process of development in nature as one going continuously forward through the combination of the opposite processes of evolution and dissolution. The tendency of our thought has been in the direction of banishing cataclysms to the theological limbo, and viewing nature as a sleepless plodder, endowed with infinite patience, waiting through long ages for results. I do not contest the truth of the principle of continuity on which this view is based. But it fails to make known to us the whole truth. The building of a ship from the time that her keel is laid until she is making her way across the ocean is a slow and gradual process; yet there is a cataclysmic epoch opening up a new era in her history. It is the moment when, after lying for months or years a dead, inert, immovable ma.s.s, she is suddenly endowed with the power of motion, and, as if imbued with life, glides into the stream, eager to begin the career for which she was designed.

I think it is thus in the development of humanity. Long ages may pa.s.s during which a race, to all external observation, appears to be making no real progress. Additions may be made to learning, and the records of history may constantly grow, but there is nothing in its sphere of thought, or in the features of its life, that can be called essentially new. Yet, nature may have been all along slowly working in a way which evades our scrutiny until the result of her operations suddenly appears in a new and revolutionary movement, carrying the race to a higher plane of civilization.

It is not difficult to point out such epochs in human progress. The greatest of all, because it was the first, is one of which we find no record either in written or geological history. It was the epoch when our progenitors first took conscious thought of the morrow, first used the crude weapons which nature had placed within their reach to kill their prey, first built a fire to warm their bodies and cook their food.

I love to fancy that there was some one first man, the Adam of evolution, who did all this, and who used the power thus acquired to show his fellows how they might profit by his example. When the members of the tribe or community which he gathered around him began to conceive of life as a whole,--to include yesterday, to-day, and to-morrow in the same mental grasp--to think how they might apply the gifts of nature to their own uses,--a movement was begun which should ultimately lead to civilization.

Long indeed must have been the ages required for the development of this rudest primitive community into the civilization revealed to us by the most ancient tablets of Egypt and a.s.syria. After spoken language was developed, and after the rude representation of ideas by visible marks drawn to resemble them had long been practiced, some Cadmus must have invented an alphabet. When the use of written language was thus introduced, the word of command ceased to be confined to the range of the human voice, and it became possible for master minds to extend their influence as far as a written message could be carried. Then were communities gathered into provinces; provinces into kingdoms; kingdoms into the great empires of antiquity. Then arose a stage of civilization which we find pictured in the most ancient records,--a stage in which men were governed by laws that were perhaps as wisely adapted to their conditions as our laws are to ours,--in which the phenomena of nature were rudely observed, and striking occurrences in the earth or in the heavens recorded in the annals of the nation.

Vast was the progress of knowledge during the interval between these empires and the century in which modern science began. Yet, if I am right in making a distinction between the slow and regular steps of progress, each growing naturally out of that which preceded it, and the entrance of the mind at some fairly definite epoch into an entirely new sphere of activity, it would appear that there was only one such epoch during the entire interval. This was when abstract geometrical reasoning commenced, and astronomical observations aiming at precision were recorded, compared, and discussed. Closely a.s.sociated with it must have been the construction of the forms of logic. The radical difference between the demonstration of a theorem of geometry and the reasoning of every-day life which the ma.s.ses of men must have practiced from the beginning, and which few even to-day ever get beyond, is so evident at a glance that I need not dwell upon it. The princ.i.p.al feature of this advance is that, by one of those antinomies of the human intellect of which examples are not wanting even in our own time, the development of abstract ideas preceded the concrete knowledge of natural phenomena.

When we reflect that in the geometry of Euclid the science of s.p.a.ce was brought to such logical perfection that even to-day its teachers are not agreed as to the practicability of any great improvement upon it, we cannot avoid the feeling that a very slight change in the direction of the intellectual activity of the Greeks would have led to the beginning of natural science. But it would seem that the very purity and perfection which was aimed at in their system of geometry stood in the way of any extension or application of its methods and spirit to the field of nature. One example of this is worthy of attention. In modern teaching the idea of magnitude as generated by motion is freely introduced. A line is described by a moving point; a plane by a moving line; a solid by a moving plane. It may, at first sight, seem singular that this conception finds no place in the Euclidian system. But we may regard the omission as a mark of logical purity and rigor. Had the real or supposed advantages of introducing motion into geometrical conceptions been suggested to Euclid, we may suppose him to have replied that the theorems of s.p.a.ce are independent of time; that the idea of motion necessarily implies time, and that, in consequence, to avail ourselves of it would be to introduce an extraneous element into geometry.

It is quite possible that the contempt of the ancient philosophers for the practical application of their science, which has continued in some form to our own time, and which is not altogether unwholesome, was a powerful factor in the same direction. The result was that, in keeping geometry pure from ideas which did not belong to it, it failed to form what might otherwise have been the basis of physical science. Its founders missed the discovery that methods similar to those of geometric demonstration could be extended into other and wider fields than that of s.p.a.ce. Thus not only the development of applied geometry, but the reduction of other conceptions to a rigorous mathematical form was indefinitely postponed.

Astronomy is necessarily a science of observation pure and simple, in which experiment can have no place except as an auxiliary. The vague accounts of striking celestial phenomena handed down by the priests and astrologers of antiquity were followed in the time of the Greeks by observations having, in form at least, a rude approach to precision, though nothing like the degree of precision that the astronomer of to-day would reach with the naked eye, aided by such instruments as he could fashion from the tools at the command of the ancients.

The rude observations commenced by the Babylonians were continued with gradually improving instruments,--first by the Greeks and afterward by the Arabs,--but the results failed to afford any insight into the true relation of the earth to the heavens. What was most remarkable in this failure is that, to take a first step forward which would have led on to success, no more was necessary than a course of abstract thinking vastly easier than that required for working out the problems of geometry. That s.p.a.ce is infinite is an unexpressed axiom, tacitly a.s.sumed by Euclid and his successors. Combining this with the most elementary consideration of the properties of the triangle, it would be seen that a body of any given size could be placed at such a distance in s.p.a.ce as to appear to us like a point. Hence a body as large as our earth, which was known to be a globe from the time that the ancient Phnicians navigated the Mediterranean, if placed in the heavens at a sufficient distance, would look like a star. The obvious conclusion that the stars might be bodies like our globe, shining either by their own light or by that of the sun, would have been a first step to the understanding of the true system of the world.

There is historic evidence that this deduction did not wholly escape the Greek thinkers. It is true that the critical student will a.s.sign little weight to the current belief that the vague theory of Pythagoras--that fire was at the centre of all things--implies a conception of the heliocentric theory of the solar system. But the testimony of Archimedes, confused though it is in form, leaves no serious doubt that Aristarchus of Samos not only propounded the view that the earth revolves both on its own axis and around the sun, but that he correctly removed the great stumbling-block in the way of this theory by adding that the distance of the fixed stars was infinitely greater than the dimensions of the earth"s...o...b..t. Even the world of philosophy was not yet ready for this conception, and, so far from seeing the reasonableness of the explanation, we find Ptolemy arguing against the rotation of the earth on grounds which careful observations of the phenomena around him would have shown to be ill-founded.

Physical science, if we can apply that term to an uncoordinated body of facts, was successfully cultivated from the earliest times. Something must have been known of the properties of metals, and the art of extracting them from their ores must have been practiced, from the time that coins and medals were first stamped. The properties of the most common compounds were discovered by alchemists in their vain search for the philosopher"s stone, but no actual progress worthy of the name rewarded the pract.i.tioners of the black art.

Perhaps the first approach to a correct method was that of Archimedes, who by much thinking worked out the law of the lever, reached the conception of the centre of gravity, and demonstrated the first principles of hydrostatics. It is remarkable that he did not extend his researches into the phenomena of motion, whether spontaneous or produced by force. The stationary condition of the human intellect is most strikingly ill.u.s.trated by the fact that not until the time of Leonardo was any substantial advance made on his discovery. To sum up in one sentence the most characteristic feature of ancient and medieval science, we see a notable contrast between the precision of thought implied in the construction and demonstration of geometrical theorems and the vague indefinite character of the ideas of natural phenomena generally, a contrast which did not disappear until the foundations of modern science began to be laid.

We should miss the most essential point of the difference between medieval and modern learning if we looked upon it as mainly a difference either in the precision or the amount of knowledge. The development of both of these qualities would, under any circ.u.mstances, have been slow and gradual, but sure. We can hardly suppose that any one generation, or even any one century, would have seen the complete subst.i.tution of exact for inexact ideas. Slowness of growth is as inevitable in the case of knowledge as in that of a growing organism. The most essential point of difference is one of those seemingly slight ones, the importance of which we are too apt to overlook. It was like the drop of blood in the wrong place, which some one has told us makes all the difference between a philosopher and a maniac. It was all the difference between a living tree and a dead one, between an inert ma.s.s and a growing organism. The transition of knowledge from the dead to the living form must, in any complete review of the subject, be looked upon as the really great event of modern times. Before this event the intellect was bound down by a scholasticism which regarded knowledge as a rounded whole, the parts of which were written in books and carried in the minds of learned men. The student was taught from the beginning of his work to look upon authority as the foundation of his beliefs. The older the authority the greater the weight it carried. So effective was this teaching that it seems never to have occurred to individual men that they had all the opportunities ever enjoyed by Aristotle of discovering truth, with the added advantage of all his knowledge to begin with. Advanced as was the development of formal logic, that practical logic was wanting which could see that the last of a series of authorities, every one of which rested on those which preceded it, could never form a surer foundation for any doctrine than that supplied by its original propounder.

The result of this view of knowledge was that, although during the fifteen centuries following the death of the geometer of Syracuse great universities were founded at which generations of professors expounded all the learning of their time, neither professor nor student ever suspected what latent possibilities of good were concealed in the most familiar operations of nature. Every one felt the wind blow, saw water boil, and heard the thunder crash, but never thought of investigating the forces here at play. Up to the middle of the fifteenth century the most acute observer could scarcely have seen the dawn of a new era.

In view of this state of things, it must be regarded as one of the most remarkable facts in evolutionary history that four or five men, whose mental const.i.tution was either typical of the new order of things or who were powerful agents in bringing it about, were all born during the fifteenth century, four of them at least at so nearly the same time as to be contemporaries.

Leonardo da Vinci, whose artistic genius has charmed succeeding generations, was also the first practical engineer of his time, and the first man after Archimedes to make a substantial advance in developing the laws of motion. That the world was not prepared to make use of his scientific discoveries does not detract from the significance which must attach to the period of his birth.

Shortly after him was born the great navigator whose bold spirit was to make known a new world, thus giving to commercial enterprise that impetus which was so powerful an agent in bringing about a revolution in the thoughts of men.

The birth of Columbus was soon followed by that of Copernicus, the first after Aristarchus to demonstrate the true system of the world. In him more than in any of his contemporaries do we see the struggle between the old forms of thought and the new. It seems almost pathetic and is certainly most suggestive of the general view of knowledge taken at that time that, instead of claiming credit for bringing to light great truths before unknown, he made a labored attempt to show that, after all, there was nothing really new in his system, which he claimed to date from Pythagoras and Philolaus. In this connection it is curious that he makes no mention of Aristarchus, who I think will be regarded by conservative historians as his only demonstrated predecessor. To the hold of the older ideas upon his mind we must attribute the fact that in constructing his system he took great pains to make as little change as possible in ancient conceptions.