AD SANCTISSIMUM DOMINUM PAULUM III. PONTIFICEM MAXIMUM, Nicolai Copernici Praefatio in libros Revolutionum. To the most holy lord Paul III, Supreme Pontiff: Nicolaus Copernicus's preface to the books on the revolutions.
Satis equidem, Sanctissime Pater, aestimare possum, futurum esse, ut simul atque quidam acceperint, me hisce meis libris, quos de Revolutionibus sphaerarum mundi scripsi, terrae globo tribuere quosdam motus, statim me explodendum cum tali opinione clamitent. Neque enim ita mihi mea placent, ut non perpendam, quid alii de illis iudicaturi sint. I can well judge, most holy Father, that as soon as certain people learn that in these books of mine, which I have written on the revolutions of the spheres of the world, I attribute certain motions to the earthly globe, they will immediately cry out that I should be rejected together with such an opinion. I am not so pleased with my own thoughts that I do not weigh what others will judge of them.
Et quamvis sciam, hominis philosophi cogitationes esse remotas a iudicio vulgi, propterea quod illius studium sit veritatem omnibus in rebus, quatenus id a Deo rationi humanae permissum est, inquirere, tamen alienas prorsus a rectitudine opiniones fugiendas censeo. And although I know that the thoughts of a philosopher are far removed from the judgment of the crowd, because his study is to seek truth in all things so far as God has permitted it to human reason, nevertheless I think that opinions wholly foreign to correctness must be avoided.
Itaque cum mecum ipse cogitarem, quam absurdum ἀκρόαμα existimaturi essent illi, qui multorum seculorum iudiciis hanc opinionem confirmatam norunt, quod terra immobilis in medio caeli, tanquam centrum illius posita sit, si ego contra assererem terram moveri, diu mecum haesi, an meos commentarios in eius motus demonstrationem conscriptos in lucem darem, an vero satius esset, Pythagoreorum et quorundam aliorum sequi exemplum, qui non per literas, sed per manus tradere soliti sunt mysteria philosophiae propinquis et amicis duntaxat. Therefore, when I considered with myself how absurd a thing those would judge it to be, who know this opinion confirmed by the judgments of many centuries, that the earth is immobile in the middle of the heavens as its center, if I should assert against this that the earth moves, I hesitated for a long time whether to bring to light my commentaries written to demonstrate its motion, or whether it would be better to follow the example of the Pythagoreans and certain others, who were accustomed to hand down the mysteries of philosophy not by writing but by hand, only to relatives and friends.
Sicut Lysidis ad Hipparchum epistola testatur. Ac mihi quidem videntur id fecisse: non ut quidam arbitrantur ex quadam invidentia communicandarum doctrinarum, sed ne res pulcherrimae, et multo studio magnorum virorum investigatae, ab illis contemnerentur, quos aut piget ullis literis bonam operam impendere, nisi quaestuosis, aut si exhortationibus et exemplo aliorum ad liberale studium philosophiae excitentur, tamen propter stupiditatem ingenii inter philosophos, tanquam fuci inter apes versantur. As the letter of Lysis to Hipparchus testifies. And indeed they seem to me to have done this not, as some suppose, from envy about communicating doctrines, but lest most beautiful things, investigated by the great labor of great men, be despised by those who are too lazy to spend honest effort on any letters unless they are profitable, or who, even if stirred by exhortations and by the example of others toward the liberal study of philosophy, still move among philosophers, because of the dullness of their mind, like drones among bees.
Cum igitur haec mecum perpenderem, contemptus, qui mihi propter novitatem et absurditatem opinionis metuendus erat, propemodum impulerat me, ut institutum opus prorsus intermitterem. When, therefore, I weighed these things with myself, the contempt that I had to fear because of the novelty and absurdity of the opinion almost drove me to abandon the work I had undertaken altogether.
Verum amici me diu cunctantem atque etiam reluctantem retraxerunt, inter quos primus fuit Nicolaus Schonbergius Cardinalis Capuanus, in omni genere doctrinarum celebris. Proximus illi vir mei amantissimus Tidemannus Gisius, episcopus Culmensis, sacrarum ut est, et omnium bonarum literarum studiosissimus. But friends drew me back while I delayed for a long time and even resisted. First among them was Nicolaus Schonberg, Cardinal of Capua, celebrated in every kind of learning. Next to him was Tiedemann Giese, bishop of Culm, a man most devoted to me and, as he was, most zealous for sacred and all good letters.
Is etenim saepenumerò me adhortatus est, et convitiis interdum additis efflagitavit, ut librum hunc ederem, et in lucem tandem prodire sinerem, qui apud me pressus non in nonum annum solum, sed iam in quartum novennium, latitasset. Idem apud me egerunt alii non pauci viri eminentissimi et doctissimi, adhortantes ut meam operam ad communem studiosorum Mathematices utilitatem, propter conceptum metum, conferre non recusarem diutius. For he very often urged me, and sometimes with reproaches added demanded, that I publish this book and at last allow it to come into the light, since it had lain hidden with me, suppressed not merely for nine years but already for a fourth period of nine years. Many other most eminent and learned men did the same with me, urging that I should no longer refuse, because of a fear I had conceived, to contribute my labor to the common benefit of students of mathematics.
Fore ut quanto absurdior plerisque nunc haec mea doctrina de terrae motu videretur, tanto plus admirationis atque gratiae habitura esset, postquam per editionem commentariorum meorum caliginem absurditatis sublatam viderent liquidissimis demonstrationibus. His igitur persuasoribus, eaque spe adductus, tandem amicis permisi, ut editionem operis, quam diu a me petissent, facerent. They said that the more absurd this doctrine of mine concerning the motion of the earth now seemed to most people, the more admiration and favor it would have once, through the publication of my commentaries, they saw the fog of absurdity removed by the clearest demonstrations. Persuaded by these men, and led by that hope, I finally allowed my friends to make the edition of the work that they had long sought from me.
At non tam mirabitur fortasse Sanctitas tua, quod has meas lucubrationes edere in lucem ausus sim, posteaquam tantum operae in illis elaborandis, mihi sumpsi, ut meas cogitationes de terrae motu etiam literis committere non dubitaverim, sed quod magis ex me audire expectat, qui mihi in mentem venerit, ut contra receptam opinionem Mathematicorum, ac propemodum contra communem sensum, ausus fuerim imaginari aliquem motum terrae. But perhaps Your Holiness will not so much wonder that I dared to publish these night-labors of mine, after I had taken so much pains in working them out that I did not hesitate to entrust my thoughts on the motion of the earth even to letters; rather, what you expect more to hear from me is how it came into my mind that, against the accepted opinion of mathematicians and almost against common sense, I dared to imagine some motion of the earth.
Itaque nolo Sanctitatem tuam latere, me nihil aliud movisse, ad cogitandum de alia ratione subducendorum motuum sphaerarum mundi, quam quod intellexi, Mathematicos sibi ipsis non constare in illis perquirendis. Primum enim usque adeo incerti sunt de motu Solis et Lunae, ut nec vertentis anni perpetuam magnitudinem demonstrare et observare possint. Therefore I do not wish Your Holiness to be unaware that nothing else moved me to think about another method of calculating the motions of the spheres of the world than that I understood mathematicians not to be consistent with themselves in investigating them. First, they are so uncertain about the motion of the sun and moon that they cannot demonstrate and observe the constant length of the turning year.
Deinde in constituendis motibus, cum illarum, tum aliarum quinque errantium stellarum, neque iisdem principiis et assumptionibus, ac apparentium revolutionum motuumque demonstrationibus, utuntur. Alii namque circulis homocentris solum, alii eccentricis et epicyclis, quibus tamen quaesita ad plenum non assequuntur. Nam qui homocentris confisi sunt, etsi motus aliquos diversos ex eis componi posse demonstraverint, nihil tamen certi, quod nimirum phaenomenis responderet, inde statuere potuerunt. Next, in establishing the motions both of those bodies and of the other five wandering stars, they do not use the same principles and assumptions, nor the same demonstrations of apparent revolutions and motions. Some use only homocentric circles, others eccentrics and epicycles, by which nevertheless they do not fully attain what is sought. For those who relied on homocentrics, although they demonstrated that some different motions could be composed from them, still could establish nothing certain from them that would answer to the phenomena.
Qui vero excogitaverunt eccentrica, etsi magna ex parte apparentes motus congruentibus per ea numeris absoluisse videantur: pleraque tamen interim admiserunt, quae primis principiis, de motus aequalitate, videntur contravenire. Rem quoque praecipuam, hoc est mundi formam, ac partium eius certam symmetriam non potuerunt invenire, vel ex illis colligere. Those, however, who devised eccentrics, although they seem for the most part to have accounted for the apparent motions by suitable numbers through them, nevertheless admitted many things meanwhile that appear to violate the first principles concerning the equality of motion. Nor were they able to find, or gather from these, the chief matter: the form of the world and the definite symmetry of its parts.
Sed accidit eis perinde, ac si quis a diversis locis, manus, pedes, caput, aliaque membra, optime quidem, sed non unius corporis comparatione, depicta sumeret, nullatenus invicem sibi respondentibus, ut monstrum potius quam homo ex illis componeretur. Itaque in processu demonstrationis, quam μέθοδον vocant, vel praeteriisse aliquid necessariorum vel alienum quid, et ad rem minime pertinens, admisisse inveniuntur. Id quod illis minime accidisset, si certa principia sequuti essent. But it happens to them as if someone took, from different places, hands, feet, head, and other members, drawn very well indeed but not in relation to one body and in no way corresponding to one another, so that from them a monster rather than a human being would be composed. Thus in the process of demonstration, which they call method, they are found either to have passed over something necessary or to have admitted something foreign and least pertinent to the matter. This would by no means have happened to them if they had followed fixed principles.
Nam si assumptae illorum hypotheses non essent fallaces, omnia quae ex illis sequuntur, verificarentur procul dubio. Obscura autem licet haec sint, quae nunc dico, tamen suo loco fient apertiora. For if their assumed hypotheses were not deceptive, everything that follows from them would without doubt be verified. Although the things I now say are obscure, they will nevertheless become clearer in their proper place.
Hanc igitur incertitudinem Mathematicarum traditionum, de colligendis motibus sphaerarum orbis, cum diu mecum revolverem, coepit me taedere, quod nulla certior ratio motuum machinae mundi, qui propter nos, ab optimo et regularissimo omnium opifice, conditus esset, philosophis constaret, qui alioqui rerum minutissimarum, respectu eius orbis, tam exquisite scrutarentur. Therefore, when I had long turned over with myself this uncertainty of the mathematical traditions about collecting the motions of the spheres of the world, it began to weary me that no more certain account of the motions of the machine of the world, which had been made for our sake by the best and most regular craftsman of all, was established among philosophers, who otherwise examine so exquisitely things most minute in comparison with that world.
Quare hanc mihi operam sumpsi, ut omnium philosophorum, quos habere possem, libros relegerem, indagaturus, an ne ullus unquam opinatus esset, alios esse motus sphaerarum mundi, quam illi ponerent, qui in scholis Mathemata profiterentur. Ac reperi quidem apud Ciceronem primum, Nicetum sensisse terram moveri. For this reason I took upon myself the labor of rereading the books of all the philosophers I could obtain, to investigate whether anyone had ever thought that there were other motions of the spheres of the world than those set down by those who profess mathematics in the schools. And I found first in Cicero that Nicetas had thought the earth moves.
Postea et apud Plutarchum inveni quosdam alios in ea fuisse opinione, cuius verba, ut sint omnibus obvia, placuit hic adscribere: οἱ μὲν ἄλλοι μένειν τὴν γῆν, φιλόλαος δὲ Πυθαγόρειος κύκλῳ περιφέρεσθαι περὶ τὸ πῦρ κατακυκλοῦ λοξοῦ ὁμοιοτροπῶς ἡλίῳ καὶ σελήνη. Ἡρακλείδης ὁ ποντικὸς καὶ ἔκφαντος ὁ Πυθαγόρειος κινοῦσι μὲν τὴν γῆν οὐ μήν γε μεταβατικῶς, τροχοῦ δίκην ἐνζωνισμένην ἀπὸ δυσμῶν ἐπὶ ἀνατολὰς, περὶ τὸ ἴδιον αὐτῆς κέντρον. Afterward I also found in Plutarch that certain others had been of this opinion. I have chosen to write his words here, so that they may be available to everyone: the others say the earth remains at rest, but Philolaus the Pythagorean says it is carried in a circle around the fire, in an oblique circle, in the same manner as the sun and moon. Heraclides of Pontus and Ecphantus the Pythagorean make the earth move, not by changing place, but like a wheel turning from west to east around its own center.
Inde igitur occasionem nactus, coepi et ego de terrae mobilitate cogitare. Et quamvis absurda opinio videbatur, tamen quia sciebam aliis ante me hanc concessam libertatem, ut quoslibet fingerent circulos ad demonstrandum phaenomena astrorum. Existimavi mihi quoque facile permitti, ut experirer, an posito terrae aliquo motu firmiores demonstrationes, quam illorum essent, inveniri in revolutione orbium caelestium possent. Having taken occasion from this, I also began to think about the mobility of the earth. And although the opinion seemed absurd, nevertheless, because I knew that others before me had been granted this freedom, to invent whatever circles they wished for demonstrating the phenomena of the stars, I judged that it would easily be permitted to me as well to try whether, once some motion of the earth was posited, firmer demonstrations than theirs could be found in the revolution of the heavenly orbs.
Atque ita ego positis motibus, quos terrae infra in opere tribuo, multa et longa observatione tandem reperi, quod si reliquorum siderum errantium motus, ad terrae circulationem conferantur, et supputentur pro cuiusque sideris revolutione, non modo illorum phaenomena inde sequantur, sed et siderum atque orbium omnium ordines, magnitudines, et caelum ipsum ita connectat, ut in nulla sui parte possit transponi aliquid, sine reliquarum partium, ac totius universitatis confusione. And so, having posited the motions that I attribute to the earth below in the work, by much and long observation I finally found that, if the motions of the remaining wandering stars are compared with the circulation of the earth and computed according to the revolution of each star, not only do their phenomena follow from this, but also the orders and magnitudes of all the stars and orbs, and the heaven itself, are so connected that nothing in any part of it can be transposed without confusion of the remaining parts and of the whole universe.
Proinde quoque et in progressu operis hunc sequutus sum ordinem ut in primo libro describam omnes positiones orbium, cum terrae, quos ei tribuo, motibus, ut is liber contineat communem quasi constitutionem universi. In reliquis vero libris postea confero reliquorum siderum atque omnium orbium motus, cum terrae mobilitate, ut inde colligi possit, quatenus reliquorum siderum atque orbium motus et apparentiae salvari possint, si ad terrae motus conferantur. Accordingly, in the course of the work I have followed this order: in the first book I describe all the positions of the orbs together with the motions of the earth that I attribute to it, so that this book contains something like the common constitution of the universe. In the remaining books I afterward compare the motions of the other stars and of all the orbs with the mobility of the earth, so that from this it may be gathered how far the motions and appearances of the other stars and orbs can be preserved if they are compared with the motions of the earth.
Neque dubito, quin ingeniosi atque docti Mathematici mihi astipulaturi sint, si quod haec philosophia in primis exigit, non obiter, sed penitus, ea quae ad harum rerum demonstrationem a me in hoc opere, afferuntur, cognoscere atque expendere voluerint. Nor do I doubt that ingenious and learned mathematicians will support me, if, as this philosophy especially requires, they are willing to know and weigh not superficially but thoroughly the things brought forward by me in this work for the demonstration of these matters.
Ut vero pariter docti atque indocti viderent, me nullius omnino subterfugere iudicium, malui tuae Sanctitati, quam cuiquam alteri has meas lucubrationes dedicare, propterea quod et in hoc remotissimo angulo terrae, in quo ego ago, ordinis dignitate, et literarum omnium atque Mathematices etiam amore, eminentissime habearis, ut facile tua authoritate et iudicio calumniantium morsus reprimere possis, etsi in proverbio sit, non esse remedium adversus sycophantae morsum. But so that learned and unlearned alike might see that I avoid no one's judgment at all, I preferred to dedicate these night-labors of mine to Your Holiness rather than to anyone else, because even in this most remote corner of the earth where I live you are held most eminent both for the dignity of your order and for your love of all letters and also of mathematics, so that by your authority and judgment you may easily restrain the bites of slanderers, although it is said in the proverb that there is no remedy against the bite of a sycophant.
Si fortasse erunt ματαιόλογοι, qui cum omnium Mathematum ignari sint, tamen de illis iudicium sibi sumunt, propter aliquem locum scripturae, male ad suum propositum detortum, ausi fuerint meum hoc institutum reprehendere ac insectari: illos nihil moror, adeo ut etiam illorum iudicium tanquam temerarium contemnam. Non enim obscurum est Lactantium, celebrem alioqui scriptorem, sed Mathematicum parum, admodum pueriliter de forma terrae loqui, cum deridet eos, qui terram globi formam habere prodiderunt. If perhaps there will be empty talkers who, although ignorant of all mathematics, nevertheless take judgment upon themselves concerning them and, because of some passage of Scripture badly twisted to their purpose, dare to criticize and attack this undertaking of mine, I pay them no attention, so much so that I even despise their judgment as rash. For it is not obscure that Lactantius, otherwise a celebrated writer but little of a mathematician, speaks very childishly about the form of the earth when he mocks those who have handed down that the earth has the form of a globe.
Itaque non debet mirum videri studiosis, si qui tales nos etiam ridebunt. Mathemata mathematicis scribuntur, quibus et hi nostri labores, si me non fallit opinio, videbuntur etiam Reipublicae ecclesiasticae conducere aliquid, cuius principatum tua Sanctitas nunc tenet. Therefore it ought not seem strange to students if such people also laugh at us. Mathematics is written for mathematicians, to whom these labors of ours, if my opinion does not deceive me, will also seem to contribute something to the ecclesiastical commonwealth, whose principate Your Holiness now holds.
Nam non ita multo ante sub Leone X, cum in Concilio Lateranensi vertebatur quaestio de emendando Calendario Ecclesiastico, quae tum indecisa hanc solummodo ob causam mansit, quod annorum et mensium magnitudines, atque Solis et Lunae motus nondum satis dimensi haberentur. Ex quo equidem tempore, his accuratius observandis, animum intendi, admonitus a praeclarissimo viro D. Paulo episcopo Semproniensi, qui tum isti negotio praeerat. For not very long ago, under Leo X, when the question of correcting the ecclesiastical calendar was being considered in the Lateran Council, it then remained undecided for this reason alone: that the lengths of years and months, and the motions of the sun and moon, had not yet been measured sufficiently. From that time I indeed directed my mind to observing these things more accurately, having been admonished by the most distinguished man, Lord Paul, bishop of Fossombrone, who then presided over that matter.
Quid autem praestiterim ea in re, tuae Sanctitatis praecipue, atque omnium aliorum doctorum Mathematicorum iudicio relinquo, et ne plura de utilitate operis promittere tuae Sanctitati videar, quam praestare possim, nunc ad institutum transeo. What I have accomplished in that matter I leave especially to the judgment of Your Holiness and of all other learned mathematicians; and lest I seem to promise Your Holiness more about the usefulness of the work than I can provide, I now pass to the undertaking.