Copernicus had the good sense to delay publication of his work until after his death - he also had the services of Osiander to write an apologetic preface stressing that his theories were not to be taken as theologically controversial ( in spite of the fact that they quite obviously were ).
Nicholas Copemicus
(1473-1543)
That Nicholas Copernicus delayed until near death to publish De revolutionibus has been taken as a sign
that he was well aware of the possible furor his work might incite; certainly his preface to Pope Paul III
anticipates many of the objections it raised. But he could hardly have anticipated that he would
eventually become one of the most famous people of all time on the basis of a book that comparatively
few have actually read (and fewer still understood) in the 450 years since it was first printed.
Copernicus was bom into a well-to-do mercantile family in 1473, at Torun, Poland. After the death of his
father, he was sponsored by his uncle, Bishop Watzenrode, who sent him first to the University of
Krakow, and then to study in Italy at the universities of Bologna, Padua and Ferrara. His concentrations
there were law and medicine, but his lectures on the subject at the University of Rome in 1501 already
evidenced his interest in astronomy. Returning to Poland, he spent the rest of his life as a church canon
under his uncle, though he also found time to practice medicine and to write on monetary reform, not to
mention his work as an astronomer.
In 1514, Copernicus privately circulated an outline of his thesis on planetary motion, but actual
publication of De revolutionibus orbium coelestium (On the Revolutions of the Heavenly Spheres)
containing his mathematical proofs did not occur until 1543, after a supporter named Rheticus had
impatiently taken it upon himself to publish a brief description of the Copernican system (Narratio
prima) in 1541. Most of De revolutionibus requires a great deal of the modem reader, since sixteenth
century methods of mathematical proofs are quite foreign to us; this is evident in the section of Book VI
that is included. However, Book I and Copernicus' preface are more readily accessible. It must be noted
that the foreword by Andreas Osiander was not authorized Copernicus, and that Osiander, who oversaw
the book's printing, included it without the author's knowledge and without identifying Osiander as its
author.
NICHOLAS COPERNICUS
OF TORUÑ
SIX BOOKS ON
THE REVOLUTIONS OF THE HEAVENLY
SPHERES
Diligent reader, in this work, which has just been
created and published, you have the motions of the
fixed stars and planets, as these motions have been
reconstituted on the basis of ancient as well as recent
observations, and have moreover been embellished by
new and marvelous hypotheses. You also have most
convenient tables, from which you will be able to
compute those motions with the utmost case for any
time whatever. Therefore buy, read, and enjoy [this
work].
Let no one untrained in geometry enter here.
NUREMBERG
JOHANNES PETREIUS
1543
XIX
[FOREWORD BY ANDREAS OSIANDER
To the Reader
Concerning the Hypotheses of this Work
There have already been widespread reports about the novel hypotheses of this
work, which declares that the earth moves whereas the sun is at rest in the center
of the universeHence certain scholars, I have no doubt, are deeply offended and
believe that the liberal arts, which were established long ago on a sound basis,
should not be thrown into confusion. But if these men are willing to examine the
matter closely, they will find that the author of this work has done nothing blameworthy. For it is the duty of an astronomer to compose the history of the
celestial motions through careful and expert study. Then he must conceive and
devise the causes of these motions or hypotheses about them. Since he cannot in
any way attain to the true causes, he will adopt whatever suppositions enable the
motions to be computed correctly from the principles of geometry for the future as
well as for the past. The present author has performed both these duties
excellently. For these hypotheses need not be true nor even probable. On the
contrary, if they provide a calculus consistent with the observations, that alone is
enough. Perhaps there is someone who is so ignorant of geometry and optics that
he regards the epicyclc of Venus as probable, or thinks that it is the reason why
Venus sometimes precedes and sometimes follows the sun by forty degrees and
even more. Is there anyone who is not aware that from this assumption it
necessarily follows that the diameter of the planet at perigee should appear more
than four times, and the body of the planet more than sixteen times, as great as at
apogee? Yet this variation is refuted by the experience of every age. In this science
there are some other no less important absurdities, which need not be set forth at
the moment. For this art, it is quite clear, is completely and absolutely ignorant of
the causes of the apparent nonuniform motions. And if any causes are devised by
the imagination, as indeed very many are, they are not put forward to convince
anyone that are true, but merely to provide a reliable basis for computation.
However, since different hypotheses are sometimes offered for one and the same
motion (for example, eccentricity and an epicycle for the sun's motion), the
astronomer will take as his first choice that hypothesis which is the easiest to
grasp. The philosopher will perhaps rather seek the semblance of the truth. But
neither of them will understand or state anything certain, unless it has been
divinely revealed to him.
Therefore alongside the ancient hypotheses, which are no more probable, let us
permit these new hypotheses also to become known, especially since they are
admirable as well as simple and bring with them a huge treasure of very skillful
observations. So far as hypotheses are concerned, let no one expect anything
certain from astronomy, which cannot furnish it, lest he accept as the truth ideas
conceived for another purpose, and depart from this study a greater fool than when
he entered it. Farewell.
XX
LETTER OF NICHOLAS SCHÖNBERG
Nicholas Schönberg, Cardinal of Capua,
to Nicholas Copernicus, Greetings.
Some years ago word reached me concerning your proficiency, of which everybody constantly spoke. At that time I began to have a very high regard for
you, and also to congratulate our contemporaries among whom you enjoyed such
great prestige. For I had learned that you had not merely mastered the discoveries
of the ancient astronomers uncommonly well but had also formulated a new
cosmology. In it you maintain that the earth moves; that the sun occupies the
lowest, and thus the central, place in the universe; that the eighth heaven remain
perpetually motionless and fixed; and that, together with the elements included in
its sphere, the moon, situated between the heavens of Mars and Venus, revolves
around the sun in the period of a year. I have also learned that you have written an
exposition of this whole system of astronomy, and have computed the planetary
motions and set them down in tables, to the greatest admiration of all. Therefore
with the utmost earnestness I entreat you, most learned sir, unless I inconvenience
you, to communicate this discovery of yours to scholars, and at the earliest
possible moment to send me your writings on the sphere of the universe together
with the tables and whatever else you have that is relevant to this subject.
Moreover, I have instructed Theodoric of Reden to have everything copied in your
quarters at my expense and dispatched to me. If you gratify my desire in this
matter, you will see that you are dealing with a man who is zealous for your
reputation and eager to do justice to so fine a talent. Farewell.
Rome, 1 November 1536
XXI
TO HIS HOLINESS, POPE PAUL III,
NICHOLAS COPERNICUS' PREFACE
TO HIS BOOKS ON THE REVOLUTIONS
I can readily imagine, Holy Father, that as soon as some people hear that in this
volume, which I have written about the revolutions of the spheres of the universe, I
ascribe certain motions to the terrestrial globe, they will shout that I must be
immediately repudiated together with this belief For I am not so enamored of my
own opinions that I disregard what others may think of them. I am aware that a
philosopher's ideas are not subject to the judgement of ordinary persons, because it
is his endeavor to seek the truth in all things, to the extent permitted to human
reason by God. Yet I hold that completely erroneous views should be shunned.
Those who know that the consensus of many centuries has sanctioned the
conception that the earth remains at rest in the middle of the heaven as its center
would, I reflected, regard it as an insane pronouncement if I made the opposite
assertion that the earth moves. Therefore I debated with myself for a long time
whether to publish the volume which I wrote to prove the earth's motion or rather
to follow the example of the Pythagoreans and certain others, who used to transmit
philosophy's secrets only to kinsmen and friends, not in writing but by word of
mouth, as is shown by Lysis' letter to Hipparchus. And they did so, it seems to me,
not, as some suppose, because they were in some way jealous about their
teachings, which would be spread around; on the contrary, they wanted the very
beautiful thoughts attained by great men of deep devotion not to be ridiculed by
those who are reluctant to exert themselves vigorously in any literary pursuit
unless it is lucrative; or if they are stimulated to the nonacquisitive study of
philosophy by the exhortation and example of others, yet because of their dullness
of mind they play the same part among philosophers as drones among bees. When
I weighed these considerations, the scorn which I had reason to fear on account of
the novelty and unconventionality of my opinion almost induced me to abandon
completely the work which I had undertaken.
But while I hesitated for a long time and even resisted, my friends drew me back.
Foremost among them was the cardinal of Capua, Nicholas Schönberg, renowned
in every field of learning. Next to him was a man who loves me dearly, Tiedemann
Giese, bishop of Chelmno, a close student of sacred letters as well as of all good
literature. For he repeatedly encouraged me and, sometimes adding reproaches,
urgently requested me to publish this volume and finally permit it to appear after
being buried among my papers and lying concealed not merely until the ninth year
but by now the fourth period of nine years. The same conduct was recommended
to me by not a few other very eminent scholars. They exhorted me no longer to
refuse, on account of the fear which I felt, to make my work available for the
general use of students of astronomy. Ile crazier my doctrine of the earth's motion
now appeared to most people, the argument ran, so much the more admiration and
thanks would it gain after they saw the publication of my writings dispel the fog of
absurdity by most luminous proofs. Influenced therefore by these persuasive men
and by this hope, in the end I allowed my friends to bring out an edition of the
volume, as they had long besought me to do.
However, Your Holiness will perhaps not be greatly surprised that I have dared to
publish my studies after devoting so much effort to working them out that I did not
hesitate to put down my thoughts about the earth's motion in written fcrm too. But
you are rather waiting to hear from me how it occurred to me to venture to
conceive any motion of the earth, against the traditional opinion of astronomers
and almost against common sense. I have accordingly no desire to from Your
Holiness that I was impelled to consider a different system of deducing the
motions of the universe's spheres for no other reason than the realization that
astronomers do not agree among themselves in their investigations of this subject.
For, in the first place, they are so uncertain about the motion of the sun and moon
that they cannot establish and observe a constant length even for the tropical year.
Secondly, in determining the motions not only of these bodies but also of the other
five planets, they do not use the same principles, assumptions, and explanations of
the apparent revolutions and motions. For while some employ only homocentrics, others utilize eccentrics and epicycles, and yet they do not quite reach their goal.
For although those who put their faith in homocentrics showed that some
nonuniform motions could be compounded in this way, nevertheless by this means
they were unable to obtain any incontrovertible result in absolute agreement with
the phenomena. On the other hand, those who devised the eccentrics seem thereby
in large measure to have solved the problem of the apparent motions with
appropriate calculations. But meanwhile they introduced a good many ideas which
apparently contradict the first principles of uniform motion. Nor could they elicit
or deduce from the eccentrics the principal consideration, that is, the structure of
the universe and the true symmetry of its parts. On the contrary, their experience
was just like some one taking from various places hands, feet, a head, and other
pieces, very well depicted, it may be, but not for the representation of a single
person; since these fragments would not belong to one another at all, a monster
rather than a man would be put together from them. Hence in the process of
demonstration or "method", as it is called, those who employed eccentrics are
found either to have omitted something essential or to have admitted something
extraneous and wholly irrelevant. This would not have happened to them, had they
followed sound principles. For if the hypotheses assumed by them were not false,
everything which follows from their hypotheses would be confirmed beyond any
doubt. Even though what I am now saying may be obscure, it will nevertheless
become clearer in the proper place.
For a long time, then, I reflected on this confusion in the astronomical traditions
concerning the derivation of the motions of the universe's spheres. I began to be
annoyed that the movements of the world machine, created for our sake by the best
and most systematic Artisan of all, were not understood with greater certainty by
the philosophers, who otherwise examined so precisely the most insignificant
trifles of this world. For this reason I undertook the task of rereading the works of
all the philosophers which I could obtain to learn whether anyone had ever
proposed other motions of the universe's spheres than those expounded by the
teachers of astronomy in the schools. And in fact first I found in Cicero that
Hicetas supposed the earth to move. Later I also discovered in Plutarch that certain
others were of this opinion. I have decided to set his words down here, so that they
may be available to everybody:
Some think that the earth remains at rest. But Philolaus the Pythagorean believes
that, like the sun and moon, it revolves around the fire in an oblique circle.
Heraclides of Pontus, and Ecphantus the Pythagorean make the earth move, not in
a progressive motion, but like a wheel in a rotation from west to east about its own
center.
Therefore, having obtained the opportunity from these sources, I too began to
consider the mobility of the earth. And even though the idea seemed absurd,
nevertheless I knew that others before me had been granted the freedom to imagine
any circles whatever for the purpose of explaining the heavenly phenomena.
Hence I thought that I too would be readily permitted to ascertain whether explanations sounder than those of my predecessors could be found for the
revolution of the celestial spheres on the assumption of some motion of the earth.
Having thus assumed the motions which I ascribe to the earth later on in the
volume, by long and intense study I finally found that if the motions of the other
planets are correlated with the orbiting of the earth, and are computed for the
revolution of each planet, not only do their phenomena follow therefrom but also
the order and size of all the planets and spheres, and heaven itself is so linked
together that in no portion of it can anything be shifted without disrupting the
remaining parts and the universe as a whole. Accordingly in the arrangement of
the volume too I have adopted the following order. In the first book I set forth the
entire distribution of the spheres together with the motions which I attribute to the
earth, so that this book contains, as it were, the general structure of the universe.
Then in the remaining books I correlate the motions of the other planets and of all
the spheres with the movement of the earth so that I may thereby determine to
what extent the motions and appearances of the other planets and spheres can be
saved if they are correlated with the earth's motions. I have no doubt that acute and
learned astronomers will agree with me if, as this discipline especially requires,
they are willing to examine and consider, not superficially but thoroughly, what I
adduce in this volume in proof of these matters. However, in order that the
educated and uneducated alike may see that I do not run away from the judgement
of anybody at all, I have preferred dedicating my studies to Your Holiness rather
than to anyone else. For even in this very remote comer of the earth where I live
you are considered the highest authority by virtue of the loftiness of your office
and your love for all literature and astronomy too. Hence by your prestige and
judgement you can easily suppress calumnious attacks although, as the proverb has
it, there is no remedy for a backbite.
Perhaps there will be babblers who claim to be judges of astronomy although
completely ignorant of the subject and, badly distorting some passage of Scripture
to their purpose, will dare to find fault with my undertaking and censure it. I
disregard them even to the extent of despising their criticism as unfounded. For it
is not unknown that Lactantius, otherwise an illustrious writer but hardly an
astronomer, speaks quite childishly about the earth's shape, when he mocks those
who declared that the earth has the form of a globe. Hence scholars need not be
surprised if any such persons will likewise ridicule me. Astronomy is written for
astronomers. To them my work too will seem, unless I am mistaken, to make some
contribution also to the Church, at the head of which Your Holiness now stands.
For not so long ago under Leo X the Lateran Council considered the problem of
reforming the ecclesiastical calendar. The issue remained undecided then only
because the lengths of the year and month and the motions of the sun and moon
were regarded as not yet adequately measured. From that time on, at the
suggestion of that most distinguished man, Paul, bishop of Fossombrone, who was
then in charge of this matter, I have directed my attention to a more precise study
of these topics. But what I have accomplished in this regard, I leave to the judgement of Your Holiness in particular and of all other learned astronomers.
And lest I appear to Your Holiness to promise more about the usefulness of this
volume than I can fulfill, I now turn to the work itself.
http://www.geo.utexas.edu/courses/302d/Fall_2011/Full%20text%20-%20Nicholas%20Copernicus,%20_De%20Revolutionibus%20(On%20the%20Revolutions),_%201.pdf
Topic: The Galileo Affair