The gradual acceptance of the Copernican theory of the universe Part 15

German writers, whether Lutherans or not, appear to have opposed the system more often in the last century than have the writers of other nationalities. Besides those already mentioned, one proposed an ingenious scheme in which the sun moves through s.p.a.ce followed by the planets as a comet is by its tail, the planets revolving in a plane perpendicular to that of the sun's path. A diagram of it would be cone-shaped. He included in this pamphlet, besides a list of his own books, (all published in Leipsic), a list of twenty-six t.i.tles from 1758 to 1883, books and pamphlets evidently opposed in whole or in part to the modern astronomy, and seventeen of these were in German or printed in Germany.[434] In this country at St. Louis was issued an _Astronomische Unterredung_ (1873) by J.C.W.L.; according to the late President White, a bitter attack on modern astronomy and a decision by the Scriptures that the earth is the princ.i.p.al body of the universe, that it stands fixed, and that the sun and the moon only serve to light it.[435]

[Footnote 434: Tischner: _Le Systeme Solaire se Mouvant_. (1894).]

[Footnote 435: White: I, 151.]

Such statements are futile in themselves nowadays, and are valuable only to ill.u.s.trate the advance of modern thought of which these are the little eddies. While modern astronomers know far more than Copernicus even dreamed of, much of his work still holds true today.

The world was slow to accept his system because of tradition, authority, so-called common sense, and its supposed incompatibility with scriptural pa.s.sages. Catholic and Protestant alike opposed it on these grounds; but because of its organization and authority, the Roman Catholic Church had far greater power and could more successfully hinder and delay its acceptance than could the Protestants. Consequently the system won favor slowly at first through the indifference of the authorities, then later in spite of their active antagonism. Scholars believed it long before the universities were permitted to teach it; and the rationalist movement of the 18th century, the revolt against a superst.i.tious religion, helped to overturn the age-old conception of the heavens and to bring Newtonian-Copernicanism into general acceptance.

The elements of this traditional conception are summarized in the fifth book of Bodin's _Universae Naturae Theatrum_, a scholar's account of astronomy at the close of the sixteenth century.[436] Man in his terrestrial habitation occupies the center of a universe created solely to serve him, G.o.d presides over all from the Empyrean above, sending forth his messengers the angels to guide and control the heavenly bodies. Such had been the thought of Christians for more than a thousand years. Then came the influence of a new science. Tycho Brahe "broke the crystal spheres of Aristotle"[437] by his study of the comet of 1572; Galileo's telescopes revealed many stars. .h.i.therto unknown, and partly solved the mysteries of the Milky Way; Kepler's laws explained the courses of the planets, and Newton's discovery of the universal application of the forces of attraction relieved the angels of their duties among the heavens. Thinkers like Bruno proposed the possibility of other systems and universes besides the solar one in which the earth belongs. And thus not only did man shrink in importance in his own eyes; but his conception of the heavens changed from that of a finite place inexplicably controlled by the mystical beings of a supernatural world, to one of vast and infinite s.p.a.ces traversed by bodies whose density and ma.s.s a man could calculate, whose movements he could foretell, and whose very substance he could a.n.a.lyze by the science of today. This dissolution of superst.i.tion, especially in regard to comets was notably rapid and complete after the comet of 1680.[438] Thus the rationalist movement with the new science opened men's minds to a universe composed of familiar substances and controlled by known or knowable laws with no tinge remaining of the supernatural. Today a man's theological beliefs are not shaken by the discovery of a new satellite or even a new planet, and the appearance of a new comet merely provides the newspaper editor with the subject of a pa.s.sing jest.

[Footnote 436: See translated sections in Appendix C.]

[Footnote 437: Robinson: 107.]

[Footnote 438: Ibid: 119.]

Yet it was fully one hundred and fifty years after the publication of the _De Revolutionibus_ before its system met with the general approval of scholars as well as of mathematicians; then nearly a generation more had to elapse before it was openly taught even at Oxford where the Roman Catholic and Lutheran Churches had no control.

During the latter part of this period, readers were often left free to decide for themselves as to the relative merits of the Tychonic and Copernican or Copernican-Cartesian schemes. But it took fully fifty years and more, besides, before these ideas had won general acceptance by the common people, so wedded were they to the traditional view through custom and a superst.i.tious reverence for the Bible. Briefly then, the _De Revolutionibus_ appeared in 1543; and quietly won some supporters, notably Bruno, Kepler and Galileo; the Congregations of the Index specifically opposed it in 1616 and 1633; however it continued to spread among scholars and others with the aid of Cartesianism for another fifty years till the appearance of Newton's _Principia_ in 1687. Then its acceptance rapidly became general even in Catholic Europe, till it was almost a commonplace in England by 1743, two hundred years after its first formal promulgation, and had become strong enough in Europe to cause the Congregations in 1757 to modify their stand. Thereafter opposition became a curiosity rather than a significant fact. Only the Roman Church officially delayed its recognition of the new astronomy till the absurdity of its obsolete position was brought home to it by Canon Settele's appeal in 1820.

Fifteen years later the last trace of official condemnation was removed, a little over two hundred years after the decrees had first been issued, and just before Bessel's discovery of stellar parallax at length answered one of the strongest and oldest arguments against the system. Since then have come many _apologias_ in explanation and extenuation of the Church's decided stand in this matter for so many generations.

Though Galileo himself was forced to his knees, unable to withstand his antagonists, his work lived on after him; he and Copernicus, together with Kepler and Newton stand out both as scientists and as leaders in the advance of intellectual enlightenment. The account of their work and that of their less well-known supporters, compared with that of their antagonists, proves the truth of the ancient Greek saying which Rheticus used as the motto for the _Narratio Prima_, the first widely known account of the Copernican system: "One who intends to philosophize must be free in mind."

APPENDIX A.

PTOLEMY: _Syntaxis Mathematica (Almagest)_

"That the earth has no movement of rotation," in _Opera Quae Exstant Omnia_, edidit Heiberg, Leipsic, 1898, Bk. I, sec.

7: (I, 21-25); compared with the translation into French by Halma, Paris, 1813.

By proofs similar to the preceding, it is shown that the earth cannot be transported obliquely nor can it be moved away from the center.

For, if that were so, all those things would take place which would happen if it occupied any other point than that of the center. It seems unnecessary to me, therefore, to seek out the cause of attraction towards the center when it is once evident from the phenomena themselves, that the earth occupies the center of the universe and that all heavy bodies are borne towards it; and this will be readily understood if it is remembered that the earth has been demonstrated to have a spherical shape, and according to what we have said, is placed at the center of the universe, for the direction of the fall of heavy bodies (I speak of their own motions) is always and everywhere perpendicular to an uncurved plane drawn tangent to the point of intersection. Obviously these bodies would all meet at the center if they were not stopped by the surface, since a straight line drawn to the center is perpendicular to a plane tangent to the sphere at that point.

Those who consider it a paradox that a ma.s.s like the earth is supported on nothing, yet not moved at all, appear to me to argue according to the preconceptions they get from what they see happening to small bodies about them, and not according to what is characteristic of the universe as a whole, and this is the cause of their mistake. For I think that such a thing would not have seemed wonderful to them any longer if they had perceived that the earth, great as it is, is merely a point in comparison to the surrounding body of the heaven. They would find that it is possible for the earth, being infinitely small relative to the universe, to be held in check and fixed by the forces exercised over it equally and following similar directions by the universe, which is infinitely great and composed of similar parts. There is neither up nor down in the universe, for that cannot be imagined in a sphere. As to the bodies which it encloses, by a consequence of their nature it happens that those that are light and subtle are as though blown by the wind to the outside and to the circ.u.mference, and seem to appear to us to go _up_, because that is how we speak of the s.p.a.ce above our heads that envelops us. It happens on the other hand that heavy bodies and those composed of dense parts are drawn towards the middle as towards a center, and appear to us to fall _down_, because that it is the word we apply to what is beneath our feet in the direction of the center of the earth. But one should believe that they are checked around this center by the r.e.t.a.r.ding effect of shock and of friction. It would be admitted then that the entire ma.s.s of the earth, which is considerable in comparison to the bodies falling on it, could receive these in their fall without acquiring the slightest motion from the shock of their weight or of their velocity. But if the earth had a movement which was common to it and to all other heavy bodies, it would soon seemingly outstrip them as a result of its weight, thus leaving the animals and the other heavy bodies without other support than the air, and would soon touch the limits of the heaven itself. All these consequences would seem most ridiculous if one were only even imagining them.

There are those who, while they admit these arguments because there is nothing to oppose them, pretend that nothing prevents the supposition, for instance, that if the sky is motionless, the earth might turn on its axis from west to east, making this revolution once a day or in a very little less time, or that, if they both turn, it is around the same axis, as we have said, and in a manner conformable to the relations between them which we have observed.

It has escaped these people that in regard to the appearances of the planets themselves, nothing perhaps prevents the earth from having the simpler motion; but they do not realize how very ridiculous their opinion is in view of what takes place around us and in the air. For if we grant them that the lightest things and those composed of the subtlest parts do not move, which would be contrary to nature, while those that are in the air move visibly more swiftly than those that are terrestrial; if we grant them that the most solid and heavy bodies have a swift, steady movement of their own, though it is true however that they obey impelling forces only with difficulty; they would be obliged to admit that the earth by its revolution has a movement more rapid than the movements taking place around it, since it would make so great a circuit in so short a time. Thus the bodies which do not rest on it would appear always to have a motion contrary to its own, and neither the clouds, nor any missile or flying bird would appear to go towards the east, for the earth would always outstrip them in this direction, and would antic.i.p.ate them by its own movement towards the east, with the result that all the rest would appear to move backwards towards the west.

If they should say that the atmosphere is carried along by the earth with the same speed as the earth's own revolution, it would be no less true that the bodies contained therein would not have the same velocity. Or if they were swept along with the air, no longer would anything seem to precede or to follow, but all would always appear stationary, and neither in flight nor in throwing would any ever advance or retreat. That is, however, what we see happening, since neither the r.e.t.a.r.dation nor the acceleration of anything is traceable to the movement of the earth.

APPENDIX B.

"TO HIS HOLINESS, PAUL III, SUPREME PONTIFF,

PREFACE BY NICHOLAS COPERNICUS TO HIS BOOKS ON REVOLUTIONS."

(A translation of the _Praefatio_ in Copernicus: _De Revolutionibus_; pp. 3-8.)

"I can certainly well believe, most holy Father, that, while mayhap a few will accept this my book which I have written concerning the revolutions of the spheres of the world, ascribing certain motions to the sphere of the earth, people will clamor that I ought to be cast out at once for such an opinion. Nor are my ideas so pleasing to me that I will not carefully weigh what others decide concerning them.

And although I know that the meditations of philosophers are remote from the opinions of the unlearned, because it is their aim to seek truth in all things so far as it is permitted by G.o.d to the human reason, nevertheless I think that opinions wholly alien to the right ought to be driven out. Thus when I considered with myself what an absurd fairy-tale people brought up in the opinion, sanctioned by many ages, that the earth is motionless in the midst of the heaven, as if it were the center of it, would think it if I were to a.s.sert on the contrary that the earth is moved; I hesitated long whether I would give to the light my commentaries composed in proof of this motion, or whether it would indeed be more satisfactory to follow the example of the Pythagoreans and various others who were wont to pa.s.s down the mysteries of philosophy not by books, but from hand to hand only to their friends and relatives, as the letter of Lysis to Hipparchus proves.[439] But verily they seemed to me not to have done this, as some think, from any dislike to spreading their teachings, but lest the most beautiful things and those investigated with much earnestness by great men, should be despised by those to whom spending good work on any book is a trouble unless they make profit by it; or if they are incited to the liberal study of philosophy by the exhortations and the example of others, yet because of the stupidity of their wits they are no more busily engaged among philosophers than drones among bees. When therefore I had pondered these matters, the scorn which was to be feared on account of the novelty and the absurdity of the opinion impelled me for that reason to set aside entirely the book already drawn up.

[Footnote 439: See Prowe: _Nic. Cop._: III, 128-137.]

"But friends, in truth, have brought me forth into the light again, though I long hesitated and am still reluctant; among these the foremost was Nicholas Schonberg, Cardinal of Capua, celebrated in all fields of scholars.h.i.+p. Next to him is that scholar, my very good friend, Tiedeman Giese, Bishop of Culm, most learned in all sacred matters, (as he is), and in all good sciences. He has repeatedly urged me and, sometimes even with censure, implored me to publish this book and to suffer it to see the light at last, as it has lain hidden by me not for nine years alone, but also into the fourth 'novenium'. Not a few other scholars of eminence also pleaded with me, exhorting me that I should no longer refuse to contribute my book to the common service of mathematicians on account of an imagined dread. They said that however absurd in many ways this my doctrine of the earth's motion might now appear, so much the greater would be the admiration and goodwill after people had seen by the publications of my commentaries the mists of absurdities rolled away by the most lucid demonstrations.

Brought to this hope, therefore, by these pleaders, I at last permitted my friends, as they had long besought me, to publish this work.

"But perhaps your Holiness will not be so shocked that I have dared to bring forth into the light these my lucubrations, having spent so much work in elaborating them, that I did not hesitate even to commit to a book my conclusions about the earth's motion, but that you will particularly wish to hear from me how it came into my mind to dare to imagine any motion of the earth, contrary to the accepted opinion of mathematicians and in like manner contrary to common sense. So I do not wish to conceal from your Holiness that nothing else moved me to consider some other explanation for the motions of the spheres of the universe than what I knew, namely that mathematicians did not agree among themselves in their examinations of these things. For in the first place, they are so completely undecided concerning the motion of the sun and of the moon that they could not observe and prove the constant length of the great year.[440] Next, in determining the motions of both these and the five other planets, they did not use the same principles and a.s.sumptions or even the same demonstrations of the appearances of revolutions and motions. For some used only h.o.m.ocentric circles; others, eccentrics and epicycles, which on being questioned about, they themselves did not fully comprehend. For those who put their trust in h.o.m.ocentrics, although they proved that other diverse motions could be derived from these, nevertheless they could by no means decide on any thing certain which in the least corresponded to the phenomena. But these who devised eccentrics, even though they seem for the most part to have represented apparent motions by a number [of eccentrics] suitable to them, yet in the meantime they have admitted quite a few which appear to contravene the first principles of equality of motion. Another notable thing, that there is a definite symmetry between the form of the universe and its parts, they could not devise or construct from these; but it is with them as if a man should take from different places, hands, feet, a head and other members, in the best way possible indeed, but in no way comparable to a single body, and in no respect corresponding to each other, so that a monster rather than a man would be constructed from them. Thus in the process of proof, which they call a system, they are found to have pa.s.sed over some essential, or to have admitted some thing both strange and scarcely relevant. This would have been least likely to have happened to them if they had followed definite principles. For if the hypotheses they a.s.sumed were not fallacious, everything which followed out of them would have been verified beyond a doubt. However obscure may be what I now say, nevertheless in its own place it will be made more clear.

[Footnote 440: _i.e._, the 15,000 solar years in which all the heavenly bodies complete their circuits and return to their original positions.]

"When therefore I had long considered this uncertainty of traditional mathematics, it began to weary me that no more definite explanation of the movement of the world machine established in our behalf by the best and most systematic builder of all, existed among the philosophers who had studied so exactly in other respects the minutest details in regard to the sphere. Wherefore I took upon myself the task of re-reading the books of all the philosophers which I could obtain, to seek out whether any one had ever conjectured that the motions of the spheres of the universe were other than they supposed who taught mathematics in the schools. And I found first that, according to Cicero, Nicetas had thought the earth was moved. Then later I discovered according to Plutarch that certain others had held the same opinion; and in order that this pa.s.sage may be available to all, I wish to write it down here:

"But while some say the earth stands still, Philolaus the Pythagorean held that it is moved about the element of fire in an oblique circle, after the same manner of motion that the sun and moon have. Heraclides of Pontus and Ecphantus the Pythagorean a.s.sign a motion to the earth, not progressive, but after the manner of a wheel being carried on its own axis. Thus the earth, they say, turns itself upon its own center from west to east."[441]

[Footnote 441: Plutarch: _Moralia: De Placitis Philosophorum_, Lib.

III, c. 13 (V. 326).]

When from this, therefore, I had conceived its possibility I myself also began to meditate upon the mobility of the earth. And although the opinion seemed absurd, yet because I knew the liberty had been accorded to others before me of imagining whatsoever circles they pleased to explain the phenomena of the stars, I thought I also might readily be allowed to experiment whether, by supposing the earth to have some motion, stronger demonstrations than those of the others could be found as to the revolution of the celestial sphere.

Thus, supposing these motions which I attribute to the earth later on in this book, I found at length by much and long observation, that if the motions of the other planets were added to the rotation of the earth and calculated as for the revolution of that planet, not only the phenomena of the others followed from this, but also it so bound together both the order and magnitude of all the planets and the spheres and the heaven itself, that in no single part could one thing be altered without confusion among the other parts and in all the universe. Hence, for this reason, in the course of this work I have followed this system, so that in the first book I describe all the positions of the spheres together with the motions I attribute to the earth; thus this book contains a kind of general disposition of the universe. Then in the remaining books, I bring together the motions of the other planets and all the spheres with the mobility of the earth, so that it can thence be inferred to what extent the motions and appearances of the other planets and spheres can be solved by attributing motion to the earth. Nor do I doubt that skilled and scholarly mathematicians will agree with me if, what philosophy requires from the beginning, they will examine and judge, not casually but deeply, what I have gathered together in this book to prove these things. In order that learned and unlearned may alike see that in no way whatsoever I evade judgment, I prefer to dedicate these my lucubrations to your Holiness rather than to any one else; especially because even in this very remote corner of the earth in which I live, you are held so very eminent by reason of the dignity of your position and also for your love of all letters and of mathematics that, by your authority and your decision, you can easily suppress the malicious attacks of calumniators, even though proverbially there is no remedy against the attacks of sycophants.

[Ill.u.s.tration: A photographic facsimile (reduced) of a page from Mulier's edition (1617) as "corrected" according to the _Monitum_ of the Congregations in 1620. The first writer merely underlined the pa.s.sage with marginal comment that this was to be deleted by ecclesiastical order. The second writer scratched out the pa.s.sage and referred to the second volume of Riccioli's _Almagestum Novum_ for the text of the order. The earlier writer was probably the librarian of the Florentine convent from which this book came, and wrote this soon after 1620. The later writer did his work after 1651, when Riccioli's book was published. This copy of the _De Revolutionibus_ is now in the Dartmouth College Library.]

If perchance there should be foolish speakers who, together with those ignorant of all mathematics, will take it upon themselves to decide concerning these things, and because of some place in the Scriptures wickedly distorted to their purpose, should dare to a.s.sail this my work, they are of no importance to me, to such an extent do I despise their judgment as rash. For it is not unknown that Lactantius, the writer celebrated in other ways but very little in mathematics, spoke somewhat childishly of the shape of the earth when he derided those who declared the earth had the shape of a ball.[442] So it ought not to surprise students if such should laugh at us also. Mathematics is written for mathematicians to whom these our labors, if I am not mistaken, will appear to contribute something even to the ecclesiastical state the heads.h.i.+p of which your Holiness now occupies.

For it is not so long ago under Leo X when the question arose in the Lateran Council about correcting the Ecclesiastical Calendar. It was left unsettled then for this reason alone, that the length of the year and of the months and the movements of the sun and moon had not been satisfactorily determined. From that time on, I have turned my attention to the more accurate observation of these, at the suggestion of that most celebrated scholar, Father Paul, a bishop from Rome, who was the leader then in that matter. What, however, I may have achieved in this, I leave to the decision of your Holiness especially, and to all other learned mathematicians. And lest I seem to your Holiness to promise more about the value of this work than I can perform, I now pa.s.s on to the undertaking.

[Footnote 442: These two sentences the Congregations in 1620 ordered struck out, as part of their "corrections."]

APPENDIX C.

THE DRAMA OF UNIVERSAL NATURE: in which are considered the efficient causes and the ends of all things, discussed in a connected series of five books, by JEAN BODIN, (Frankfort, 1597).

_Book V_: On the Celestial Bodies: their number, movement, size, harmony and distances compared with themselves and with the earth. Sections 1 and 10 (in part) and 12 (entire).

BODIN, JEAN: _Universae Naturae Theatrum in quo rerum omnium effectrices causa et fines contemplantur, et continuae series quinque libris discutiuntur_. Frankfort, 1597. Book V translated into English by the writer and compared with the French translation by Francois de Fougerolles, (Lyons, 1597).

_Section 1_: On the definition and the number of the spheres.