Very Reverend Father and most worthy Signore,*
I received a visit yesterday from signor Niccolò Arrighetti,* who brought me news of your Reverence. I was delighted to hear what I never doubted, namely the high opinion in which you are held by the whole university,* both the governors and the teachers and students of all nations. This approval, far from increasing the number of your rivals as usually happens among those who work in the same field, has rather reduced their number to very few—and these few will have to desist if their rivalry, which can sometimes be seen as admirable, is not to degenerate and seem rather to be blameworthy and to do more harm to their reputation than to anyone else’s. But what set the seal on my pleasure was hearing his account of the arguments which you were able to put forward, thanks to the great kindness of their Serene Highnesses, first at their dinner table and later in Madame’s* drawing-room, in the presence of the Grand Duke and the Archduchess* and the distinguished and excellent gentlemen Don Antonio* and Don Paolo Giordano and other excellent philosophers. What greater favour could you wish for than that their Highnesses should be pleased to hold conversation with you, to put their doubts to you, to hear you resolve them and finally to be satisfied with your Reverence’s replies?
The points which you made, as signor Arrighetti reported them to me, have prompted me to think afresh about some general principles concerning the citing of Holy Scripture in disputes on matters of natural science, and in particular on the passage in Joshua* which was put forward by the Dowager Grand Duchess, and to which the Archduchess offered some rejoinders, as evidence against the motion of the Earth and the fixed position of the Sun.
As regards the first general question raised by Madame, it seems to me that both she and you were entirely prudent when she asserted and you agreed that Holy Scripture can never lie or be in error, but that its decrees are absolutely and inviolably true. I would simply have added that, although Scripture cannot err, nonetheless some of its interpeters and expositors can, and in various ways. One error in particular, which is especially serious and frequent, is to insist always on the literal meaning of the words, for this can lead not only to many contradictions but also to grave heresies and blasphemies; for it would mean attributing to God feet and hands and eyes, not to mention physical human affections such as anger, repentance, hatred, and sometimes even forgetfulness of past events and ignorance of the future. So, since Scripture contains many statements which, if taken at their face value, appear to be at variance with the truth, but which are couched in these terms so as to be comprehensible to the ignorant, it is up to wise expositors to explain their true meaning to those few who deserve to be set apart from the common herd, and to point out the particular reasons why they have been expressed as they have.
Given, then, that Scripture in many places not only admits but necessarily requires an interpretation which differs from the apparent meaning of the words, it seems to me that it should be brought into scientific disputes only as a last resort. For while Holy Scripture and nature proceed alike from the divine Word—Scripture as dictated by the Holy Spirit, and nature as the faithful executor of God’s commands—it is agreed that Scripture, in order to be understood by the multitude, says many things which are apparently and in the literal sense of the words at variance with absolute truth. But nature never trangresses the laws to which it is subject, but is inexorable and unchanging, quite indifferent to whether its hidden reasons and ways of working are accessible to human understanding or not. Hence, any effect in nature which the experience of our senses places before our eyes, or to which we are led by necessary demonstrations,* should on no account be called into question because of a passage of Scripture whose words appear to suggest something different, because not every statement of Scripture is bound by such strict rules as every effect of nature. Indeed, if Scripture has not hesitated to veil some of its most important dogmas and to attribute to God himself qualities contrary to his very essence, solely so as to be accessible to the ignorant and uneducated masses, who would wish to insist that it had set aside the need to be accessible and confined itself strictly to the narrow literal meaning of the words when speaking incidentally about the Earth or the Sun or some other part of creation? This is all the more unlikely when what it says about these parts of creation are things far removed from the primary purpose of Holy Writ, but rather things which, if understood purely in their plain literal sense, would rather have undermined its primary purpose, by making the common people sceptical of its message in matters concerning salvation.
Since this is so, and since moreover it is clear that two truths can never contradict each other, it is the duty of the wise expositor to seek out the true meanings of Scripture which agree with those scientific conclusions which observation or necessary demonstrations have already established as certain. I would go further and argue that since, as we have seen, the Scriptures, albeit inspired by the Holy Spirit, often allow interpretations far removed from their literal meaning, for the reasons given above, and since moreover there is no guarantee that all interpreters are divinely inspired, it would be prudent not to allow anyone to use Scripture to uphold as true any scientific conclusions which observation and necessary demonstration might show to be false. For who would wish to place limits on human understanding, or claim that we already know all that there is to be known? So perhaps it would be wisest not to add unnecessarily to the articles concerning salvation and the foundations of the faith whose certainty is immune to valid arguments ever being raised against it. It would be even more unwise to add to them at the request of those who may or may not be inspired from above, but who are clearly devoid of the intelligence to understand, let alone to challenge, the demonstrations which the exact sciences use to validate their conclusions.
I believe that the purpose of the authority of Holy Scripture is solely to persuade men of those articles and propositions which are necessary to their salvation and which, being beyond the scope of human reasoning, could not be made credible to us by science or by any other means, but only through the mouth of the Holy Spirit himself. I do not consider it necessary to believe that the same God who has endowed us with senses, and with the power of reasoning and intellect, should have chosen to set these aside and to convey to us by some other means those facts which we are capable of finding out by exercising these faculties. This is especially the case with those sciences of which only a tiny part is to be found in scattered references in Scripture, such as astronomy, of which Scripture contains so little that it does not even mention the planets. For if the sacred writers had intended to persuade the people of the order and motions of the heavenly bodies, they would not have said so little about them—almost nothing compared to the infinite, profound, and wonderful truths which this science contains.
So you can see, Father, if I am not mistaken, how flawed is the procedure of those who, in debating questions of natural science which are not directly matters of faith,* give priority to verses of Scripture—often verses which they have misunderstood. But if they really believe that they possess the true meaning of a particular verse of Scripture, and are therefore convinced that they hold in their hand the absolute truth of the matter which they intend to debate, I would ask them to tell me frankly: do they consider that someone to whom it falls to maintain the truth in a scientific debate has a great advantage over their opponent who has to defend what is false? I know they will answer yes, and will say that the one who is defending the truth will be able to draw on numerous experiments and necessary demonstrations to support their position, while their opponent can only fall back on sophistry, false arguments, and fallacies. Why then, if they are so confident that their purely scientific and philosophical weapons are so much stronger than their adversary’s, do they immediately have recourse, as soon as battle is joined, to an awesome and irresistible weapon the very sight of which strikes terror into the heart of the most skilful and experienced fighter? If the truth be told, I believe that they are the first to be terror-struck, and that when they realize they are unable to resist the assaults of their adversary they try to find a way of not letting him come near them. But since, as I have said, whoever has the truth on their side has a great, indeed a huge, advantage over their opponent, and since it is impossible for two truths to contradict each other, we have nothing to fear from assaults on any side, as long as we are given an opportunity to speak and to be heard by persons of understanding who are not unduly swayed by their own passions and interests.
To confirm this, I come now to the particular case of Joshua, about which you presented three statements to their Highnesses; and specifically to the third of these, which you rightly attributed to me, but to which I now want to add some further considerations, which I do not believe I have yet explained to you.
So let me first concede to my adversary that the words of the sacred text should be taken in exactly their literal sense, namely that God made the Sun stand still in response to Joshua’s prayers,* so that the day was prolonged and Joshua was able to complete his victory. But let me claim the same concession for myself, lest my adversary should tie me down while remaining free himself to change or modify the meanings of words; and I will show that this passage of Scripture clearly demonstrates the impossibility of the Aristotelian and Ptolemaic world system, and on the contrary fits perfectly well with the system of Copernicus.
I ask first, does my adversary know in what ways the Sun moves? If he does, he must perforce reply that it has two motions,* an annual motion from west to east, and a daily one in the opposite direction, from east to west.
My second question then is, do these two different and almost contrary motions both belong to the Sun, and are they both proper to it? To this the answer must be no: only the annual motion is specific and proper to the Sun, while the other belongs to the highest heaven or Primum Mobile,* which draws the Sun, the other planets, and the sphere of the fixed stars along with it, making them complete a revolution around the Earth every twenty-four hours, with a motion which is, as I have said, contrary to their own natural and proper motion.
So to the third question: which of these two motions of the Sun produces day and night, the Sun’s own real motion or that of the Primum Mobile? The answer has to be that day and night are the result of the motion of the Primum Mobile, and that the Sun’s own motion produces not day and night but the changing seasons, and the year itself.
Hence it is clear that, if the length of the day depends not on the motion of the Sun but on that of the Primum Mobile, in order to prolong the day it is the Primum Mobile which must be made to stop, not the Sun. Indeed, anyone who understands these first elements of astronomy will realize that if God had stopped the motion of the Sun, the effect would have been to shorten the day, not to lengthen it. The motion of the Sun being in the opposite direction to the daily revolution of the heavens, the more the Sun moved towards the east, the more its progress towards the west would be held back; and if the Sun’s motion were diminished or stopped altogether, it would reach the point where it sets all the more quickly.* This effect can be clearly seen in the case of the Moon, whose daily revolution is slower than the Sun’s by the same amount as its own proper motion is faster than the Sun’s.* So it is simply impossible, according to the system of Ptolemy and Aristotle, to prolong the day by stopping the motion of the Sun, as Scripture says happened. It follows therefore that either the motions of the heavens are not as Ptolemy says, or we must change the sense of the words of Scripture and say that, when Scripture says that God stopped the Sun, what it meant was that God stopped the Primum Mobile. But in order to accommodate itself to the understanding of those who are hardly able to comprehend the rising and setting of the Sun, Scripture states the opposite of what it would have said if it had been speaking to men of sense.
To this we might add that it is not credible that God should have stopped only the Sun and allowed the other spheres to keep on turning, because this would unnecessarily have changed the whole order and disposition of the other spheres in relation to the Sun, which would have caused huge disruption to the whole course of nature. But it is credible that He stopped the whole system of the heavenly spheres, and that after that period of rest they all returned harmoniously to their normal operation, without any confusion or disruption of any kind.
However, since we have agreed that we should not change the meaning of the words of Scripture, we must have recourse to another arrangement of the world to see whether it agrees with the plain meaning of the words, as indeed we shall see that it does.
I have discovered and rigorously demonstrated that the globe of the Sun turns on its own axis,* making a complete revolution in the space of roughly one lunar month, in the same direction as all the other revolutions of the heavens. Moreover, it is very probable and reasonable to suppose that the Sun, as the instrument and the highest minister of nature—the heart of the world, so to speak—imparts not only light (as it clearly does) but also motion to the planets which revolve around it.* So if we follow Copernicus in attributing first of all a daily rotation to the Earth, it is clear that, to bring the whole system to a stop solely in order to prolong the extent and time of daylight without disrupting all the other relations between the planets, it was enough that the Sun should stand still, just as the words of Holy Writ say. This, then, is how the length of the day on Earth can be extended by making the Sun stand still, without introducing any confusion among the parts of the world and without altering the words of Scripture.
I have written much more than my indisposition allows, so I close by offering myself as your servant, kissing your hand and praying our Lord that you may have a joyful festive season and every happiness.
In Florence, 21 December 1613, your Reverence’s devoted servant, Galileo Galilei.
A few years ago, as your Highness well knows, I discovered many things in the heavens which had been invisible until this present age. Because of their novelty and because some consequences which follow from them contradict commonly held scientific views, these have provoked not a few professors in the schools against me, as if I had deliberately placed these objects in the sky to cause confusion in the natural sciences. They seem to forget that the increase of known truths, far from diminishing or undermining the sciences, works to stimulate the investigation, development, and strengthening of their various fields. Showing a greater fondness for their own opinions than for the truth, they have sought to deny and disprove these new facts which, if they had considered them carefully, would have been confirmed by the very evidence of their senses. To this end they have put forward various objections and published writings full of vain arguments and, more seriously, scattered with references to Holy Scripture, taken from passages they have not properly understood and which have no bearing on their argument. They might have avoided this error if they had paid attention to a salutary warning by St Augustine, on the need for caution in coming to firm conclusions about obscure matters which cannot be readily understood by the use of reason alone. Speaking about a certain scientific conclusion concerning the celestial bodies, Augustine writes:* ‘Aware of the restraint that is proper to a devout and serious person, one should not entertain any rash belief about an obscure question. Otherwise, when the truth is known, we might despise it because of our attachment to our error, even though the truth may not be in any way opposed to the sacred writings of the Old or New Testament.’
With the passing of time the truths which I first pointed out have become apparent to all, and the truth has exposed the difference in attitude between those who simply and dispassionately were unconvinced of the reality of my discoveries, and those whose incredulity was mixed with some emotional reaction. Those who were expert in astronomy and the natural sciences were convinced by my first announcement,* and the doubts of others were gradually allayed unless their scepticism was fed by something other than the unexpected novelty of my discoveries or the fact that they had not had an opportunity to confirm them by their own observations. But there are those whose attachment to their earlier error is compounded by some other imaginary self-interest which makes them hostile, not so much to the discoveries themselves as to their author. Once they can no longer deny the facts they pass over them in silence, and, distracting themselves with fantasies and embittered even more by what has pacified and won over others, they try to condemn me by other means. And indeed, I would not pay any more attention to these than to the other criticisms made against me, which I have never taken seriously as I have always been confident of prevailing in the end, were it not for the fact that these new attacks and calumnies do not stop at questioning the extent of my learning—for which I make no great claims—but try to smear me with accusations of faults which are more abhorrent to me than death itself. Even if those who know me and my accusers know that their accusations are false, I have to defend my reputation in the eyes of everyone else.
These people, persisting in their determination to use all imaginable means to destroy me and my works, know that in my astronomical and philosophical studies I maintain that the Sun remains motionless at the centre of the revolutions of the celestial globes, and that the Earth both turns on its own axis and revolves around the Sun. They know, moreover, that I uphold this position not just by refuting the arguments of Ptolemy and Aristotle, but also by putting forward many arguments to the contrary, in particular, some related to physical effects that are hard to explain in any other way. There are also astronomical arguments depending on many things in my new discoveries in the heavens, which clearly disprove the Ptolemaic system, and perfectly agree with and confirm this alternative position.* Perhaps they are dismayed by the fact that other propositions which I have put forward, which differ from those commonly held, have been shown to be true, and so have given up hope of defending themselves by strictly philosophical means; and so they have tried to hide the fallacies in their arguments under the mantle of false religion and by invoking the authority of Holy Scripture, which they have applied with little understanding to refute arguments which they have neither heard nor understood.
They began by doing their best to spread abroad the idea that these propositions are contrary to Holy Scripture, and therefore to be condemned as heretical. Then, realizing how much more readily human nature will embrace a cause which harms their neighbour, however unjustly, than one which justly encourages them, they had no difficulty in finding others who were prepared to declare from the pulpit, with uncharacteristic confidence, that they were indeed to be condemned as heretical. They showed little pity and less consideration for the injury they were doing not just to this teaching and those who follow it, but to mathematics and mathematicians everywhere.* Now, as their confidence has grown and they vainly hope that this seed, which first took root in their own insincere minds, will grow and spread its branches up to heaven, they spread the rumour that it is shortly to be condemned as heretical by the supreme authority of the Church. And since they know that such a condemnation would not just undermine these two propositions, but would extend to all the other astronomical and scientific observations and conclusions which are logically linked to them, they try to make their task easier by giving the impression, as far as they can at least among the general public, that this view is new and mine alone. They pretend not to know that its author—or rather the one who revived and confirmed it—was Nicolaus Copernicus, a man who was not just a Catholic but a priest and a canon,* and so highly esteemed that he was called to Rome from the furthest reaches of Germany to advise the Lateran Council under Pope Leo X on the revision of the ecclesiastical calendar. At that time the calendar was incorrect simply because they did not know the exact length of the year and the lunar month; so the Bishop of Fossombrone,* who was in charge of the revision, commissioned Copernicus to undertake the prolonged study necessary to establish these celestial movements with greater clarity and certainty. Copernicus set about this task and, thanks to a truly Herculean series of labours combined with his great intellect, made such great progress in this science that he was able to establish the period of the celestial movements with such a high degree of precision, that he came to be recognized as the supreme astronomer, and his findings became the basis not just for the regulation of the calendar but for tables showing the movements of all the planets.* He set his findings down in six books which he published at the request of the Cardinal of Capua and the Bishop of Kulm;* and since he had undertaken the work at the request of the Supreme Pontiff, he dedicated his book, On the Revolutions of the Heavenly Spheres, to Pope Leo’s successor, Paul III. As soon as the book was printed it was received by Holy Church and was read and studied throughout the world, without anyone expressing the slightest scruples about its content. But now that the soundness of its conclusions is being confirmed by manifest experiments and necessary demonstrations, there are those who, without even having seen the book, want to reward its author for all his labours by having him declared a heretic—and this solely to satisfy the personal grudge they have conceived for no reason against someone whose only connection with Copernicus is to have endorsed his teachings.
So I have concluded that the false accusations which these people so unjustly try to make against me leave me no choice but to justify myself in the eyes of the general public, whose judgement in matters of religion and reputation I have to take very seriously. I shall respond to the arguments which they produce for condemning and banning Copernicus’ opinion, and for having it declared not just false but heretical. Under the cloak of pretended religious zeal, they cite the Holy Scriptures to make them serve their hypocritical purposes, claiming to extend, not to say abuse, the authority of the Scriptures in a way which, if I am not mistaken, is contrary to the intention of the biblical writers and of the Fathers of the Church. They would have us, even in purely scientific questions which are not articles of faith, completely abandon the evidence of our senses and of demonstrative arguments because of a verse of Scripture whose real purpose may well be different from the apparent meaning of the words.
I hope that I can demonstrate that I am acting with greater piety and religious zeal than my opponents when I argue, not that Copernicus’ book should not be condemned, but that it should not be condemned in the way they have done, without having understood it, listened to its arguments, or even seen it. For he was an author who never wrote about matters of religion or faith, or cited arguments based in any way on the authority of Scripture, which he might have misunderstood; but he always confined himself to scientific conclusions regarding the movements of the heavens, using astronomical and geometrical proofs resting first of all on the experience of the senses and detailed observations. This is not to say that he paid no attention to what Scripture says, but he was quite clear in his mind that if his conclusions were scientifically proven, they could not contradict Scripture if it was properly understood. Hence he wrote, at the end of his dedication of the book to the Supreme Pontiff:
If there should happen to be any idle prattlers who, even though they are entirely ignorant of mathematics, nonetheless take it on themselves to pass judgement in these matters, and dare to criticize and attack this theory of mine because of some passage of Scripture that they have wrongly twisted to their purpose, it is of no consequence to me and indeed I will condemn their judgement for its rashness. It is well known that Lactantius,* in other respects a famous writer, was a poor mathematician, and shows his childish understanding of the shape of the Earth when he mocks those who said that the Earth has the form of a sphere. So we scholars should not be surprised if we too are sometimes made fun of by such people. Mathematics is written for mathematicians, and if I am not deceived, they will recognize that these labours of mine make a useful contribution to the ecclesiastical state of which Your Holiness now holds the highest office.
Such are the people who are trying to persuade us that an author like Copernicus should be condemned without even being read. To suggest that this would be not just legitimate but laudable, they cite various texts from Scripture, from theologians, and from the Councils of the Church. I revere these and hold them to be of the highest authority, and I would regard it as the height of temerity to contradict them, as long as they are used in conformity with the practice of Holy Church. Equally, I do not believe it is wrong to speak out if there is reason to suspect that someone is citing and using such texts for their own ends in a way which is at odds with the holy will of the Church. So I declare (and I believe that my sincerity will speak for itself) my willingness to submit to removing any errors which, through my ignorance in matters of religion, may be found in this letter. I declare, further, that I have no wish to enter into quarrels with anyone on such matters, even on points which may be disputable. My purpose is only that, if in these reflections which are outside my professional competence there is anything, among whatever errors they may contain, which might prompt others to find something useful to Holy Church in reaching a conclusion on the Copernican system, it may be taken and used in whatever way my superiors may decide. Otherwise let this letter be torn up and burnt, for I have no desire for any gain from it which is not in keeping with Catholic piety. Moreover, although many of the points I shall discuss are things which I have heard with my own ears, I freely grant to whoever said them that they did not say them, if that is what they wish, admitting that I could well have misunderstood them. Hence, let my reply be addressed not to them but to those who do hold the opinion in question.
The reason, then, which they give for condemning the view that the Earth moves and the Sun is stationary, is that there are many places in Holy Writ where we read that the Sun moves and the Earth does not; and since Scripture can never lie or be in error, it necessarily follows that anyone who asserts that the Sun is motionless and the Earth moves must be in error, and such a view must be condemned.
The first thing to be said on this point is that it is entirely pious to state, and prudent to affirm, that Holy Scripture can never lie, provided its true meaning has been grasped. But I do not think it can be denied that the true meaning of Scripture is often hidden and very different from the literal meaning of the words. It follows that when an expositor always insists on the bare literal sense, this error can make Scripture appear to contain not only contradictions and statements which are far removed from the truth, but even grave heresies and blasphemies; for it would mean attributing to God feet and hands and eyes, not to mention corporeal and human affections such as anger, repentance, hatred, and sometimes even forgetfulness of past events and ignorance of the future. So since the biblical writers, inspired by the Holy Spirit, stated these things in this way so as to be comprehensible to the untrained and ignorant, it is necessary for wise expositors to explain their true meaning to those few who deserve to be set apart from the common herd, and to point out the particular reasons why they have been expressed in the terms that they have. This principle is so commonplace among theologians that it would be superfluous to cite any authorities to justify it.
From this it seems reasonable to deduce that whenever Scripture has had occasion to speak about matters of natural science, especially those which are obscure and difficult to understand, it has followed this rule, so as not to cause confusion among the common people and make them more sceptical of its teaching about higher mysteries. As I have said and as is clear to see, Scripture has not hesitated to veil some of its most important statements, attributing to God himself qualities contrary to his very essence, solely in order to be accessible to popular understanding. Who then would be so bold as to insist that it had set this aside and confined itself rigorously to the narrow literal meaning of the words when speaking in passing about the Earth, water, or the Sun or some other part of creation? This is all the more unlikely since what it says about these things has nothing to do with the primary intention of Holy Writ, namely divine worship and the salvation of souls, and matters far removed from the understanding of the masses.
This being the case, it seems to me that the starting-point in disputes concerning problems in natural science should not be the authority of scriptural texts, but the experience of the senses and necessary demonstrations. For while Holy Scripture and nature proceed alike from the divine Word—Scripture as dictated by the Holy Spirit, and nature as the faithful executor of God’s commands—it is agreed that Scripture, in order to be understood by the multitude, says many things which are apparently and in the literal sense of the words at variance with absolute truth. Nature, on the other hand, never trangresses the laws to which it is subject, but is inexorable and unchanging, quite indifferent to whether its hidden reasons and ways of working are accessible to human understanding or not. Hence, any effect in nature which the experience of our senses places before our eyes, or to which we are led by necessary demonstrations, should on no account be called into question, much less condemned, because of a passage of Scripture whose words appear to suggest something different. For not every statement of Scripture is bound by such strict rules as every effect of nature, and God is revealed just as excellently in the effects of nature as in the sacred sayings of Scripture. This may be what Tertullian meant when he wrote:* ‘I conclude that knowledge of God is first to be found in nature, and then confirmed in doctrine; in nature through his works, and in doctrine through preaching.’
This is not to imply that we should not have the highest regard for the text of Scripture. On the contrary, once we have reached definite conclusions in science we should make use of them as the best means of gaining a true understanding of Scripture, and of searching out the meanings which Scripture necessarily contains, since it is absolutely true and in harmony with demonstrated truth. I believe therefore that the purpose of the authority of Holy Scripture is chiefly to persuade men of those articles and propositions which, being beyond the scope of human reasoning, could not be made credible to us by science or by any other means, but only through the mouth of the Holy Spirit. What is more, even in matters which are not articles of faith the authority of Scripture should prevail over that of any human writings which are not set out in a demonstrative way, but are simply stated or put forward as probabilities. This should be regarded as right and necessary, to the same extent that divine wisdom surpasses human understanding or conjecture. But I do not consider it necessary to believe that the same God who has endowed us with senses, and with the power of reasoning and intellect, should have chosen to set these aside and to convey to us by some other means those facts which we are capable of finding out by exercising these faculties, so that even in scientific conclusions which the evidence of our senses and necessary demonstrations set before our eyes and minds, we should deny what our senses and reason tell us. Least of all do I think this applies in those sciences of which only a tiny part is to be found in scattered references in Scripture, such as astronomy, of which Scripture contains so little that it does not even mention the planets, apart from the Sun and Moon, and once or twice Venus, under the name of Lucifer. For if the sacred writers had intended to teach the people the order and movements of the heavenly bodies, and that therefore we should learn these things from Scripture, I do not believe that they would have said so little about them—almost nothing compared to the infinite, profound, and wonderful truths which are demonstrated in this science.
Indeed, it is the opinion of the holy and learned Fathers of the Church that the biblical authors not only made no claim to teach us about the structure and movements of the heavens and stars, and their appearance, size, and distance, but that they deliberately refrained from doing so, even though these things were perfectly well known to them. In the words of St Augustine:*
It is commonly asked what we have to believe about the form and shape of heaven according to Sacred Scripture. Many engage in lengthy discussions on these matters, but our writers, with their greater prudence, have omitted them. Such subjects are of no profit for those who seek a blessed life, and, what is worse, they take up very precious time that ought to be given to what is spiritually beneficial. What concern is it of mine whether heaven is like a sphere and the Earth is enclosed by it and suspended in the middle of the universe, or whether heaven is like a disc that covers the Earth on one side? But the credibility of Scripture is at stake, and as I have indicated more than once, there is some danger for a man uninstructed in divine revelation. Discovering something in Scripture or hearing something cited from it that seems to be at variance with the knowledge he has acquired, he may doubt its truth when it offers useful admonitions, narratives, or declarations. Hence, let it be said briefly that concerning the shape of heaven the sacred writers knew the truth, but that the Spirit of God, who spoke through them, did not wish to teach men these facts that would be of no avail for their salvation.
The same lack of interest on the part of the sacred writers in laying down what should be believed about these properties of the celestial bodies is shown again by St Augustine in the next chapter, chapter 10, where on the question of whether the heavens should be deemed to be motionless or in motion, he writes:
Concerning the heaven, some of the brethren have enquired whether it is stationary or moving. If it is moving, they say, how is it a firmament? And if it is stationary, how do the heavenly bodies that are thought to be fixed in it travel from east to west, the more northerly performing smaller circles near the pole? So heaven is like a sphere, if there is another pole invisible to us, or like a disc, if there is no other axis. My reply is that a great deal of subtle and learned enquiry into these questions would be required to know which of these views is correct, but I have no time to go into these questions and discuss them. Neither have they time, those whom I wish to instruct for their own salvation and for the benefit of the Holy Church.
Coming to the particular point with which we are concerned, if the Holy Spirit has chosen not to teach us whether the heavens move or stand still, or whether they have the shape of a sphere, a disc, or a flat surface, or whether the Earth is in the middle of the heavens or to one side, it necessarily follows that He had no intention of giving us a definite answer to other questions of the same kind. The question of the motion or rest of the Earth and the Sun is so linked to those mentioned above that it cannot be determined one way or the other without first answering these. If the Holy Spirit has deliberately refrained from teaching us such things as not being relevant to his intention—that is, to our salvation—how can it be claimed that taking one or other view on this question is obligatory, and that one view is an article of faith and the other is an error? Is it then possible for an opinion to be heretical, and yet have no relevance to the salvation of souls? Or can it be claimed that the Holy Spirit has chosen not to teach us something which concerns our salvation? I cannot do better here than quote what I have heard said by a very eminent churchman,* that the intention of the Holy Spirit is to teach us how one goes to heaven, not how the heaven goes.
Returning to the question of how much weight should be given in questions of natural science to necessary demonstrations and the experience of the senses, and how much these have been regarded as authoritative by learned and holy theologians, the following are two statements among many: ‘In discussing the teaching of Moses, we should take care to avoid at all costs saying or declaring categorically ourselves anything that goes against what is clear from manifest experience and the reasoning of philosophy or other disciplines. Since any truth always agrees with every other truth, the truth of Holy Scripture cannot contradict the truth of human sciences established through experience and reason.’* And in St Augustine we read:* ‘Anyone who invokes the authority of Scripture in opposition to what is clearly and conclusively established by reason, does not understand what they are doing. What they are opposing to the truth is not the meaning of Scripture, which they have failed to grasp, but their own view, which they have found not in Scripture but in themselves.’
This granted, and since, as has been said, two truths can never contradict each other, it is the duty of the wise expositor to seek out the true meanings of Scripture, which undoubtedly will agree with those scientific conclusions which observation and necessary demonstrations have already established as certain. Now the Scriptures, as we have seen, often allow interpretations which differ from the meaning of the words, for the reasons given above. Moreover, there is no guarantee that all interpreters are divinely inspired, for if they were, they would never disagree over the meaning of a given passage. So it would be highly prudent not to allow anyone to use Scripture to uphold as true any scientific conclusion which observation and demonstrative and necessary reasons might at some time show to be false. For who can place limits on the human mind, or claim that we already know all that there is to be known? Will it be those who on other occasions admit, quite rightly, that ‘What we know is only a tiny part of what we do not know’?*
Indeed, since we have it from the mouth of the Holy Spirit that ‘He has given up the world to disputations, so that no man may find out what God made from the beginning to the end’,* I do not think we should contradict this by closing the path to free speculation concerning the natural world, as if everything had already been discovered and revealed with absolute certainty. Nor do I think it should be considered presumptuous to challenge opinions which were formerly commonplace, or that anyone should be indignant if someone does not share their opinion on a matter of scientific dispute—least of all in the case of problems which the greatest philosophers have debated for thousands of years, such as the view that the Sun is fixed and the Earth moves. This was the view held by Pythagoras and all his followers, Heraclides of Pontus, and also Plato’s teacher Philolaus, and by Plato himself, as Aristotle tells us* and as Plutarch confirms in his life of Numa,* where he writes that Plato in his old age used to say that it was absurd to believe otherwise. The same view was held by Aristarchus of Samos, as we learn from Archimedes;* by Seleucus the mathematician;* by the philosopher Nicetas, according to Cicero,* and by many others; and it has finally been developed and confirmed with numerous observations and proofs by Nicolaus Copernicus. Seneca too, that most eminent philosopher, exhorts us in his book On Comets* to make every effort to establish with certainty whether it is in the sky or on Earth that the daily rotation is located.
So perhaps it would be only wise and prudent not to add unnecessarily to the articles concerning salvation and the foundations of the faith whose certainty is immune to valid arguments ever being raised against it. It would be doubly unwise to add to them at the request of those who may or may not be inspired from above, but who clearly lack the intelligence first to understand, and then to discuss, the demonstrations which the exact sciences use to validate their conclusions. If I were allowed to give my opinion, I would go further and say that it might be more appropriate, and more befitting the dignity of Holy Writ, to stop every lightweight popular writer from trying to lend authority to their writings, often based on empty fancies, by quoting verses from Scripture, which they interpret or rather force into saying things which are as far from the true meaning of Scripture as they are near to making complete fools of themselves when they parade their biblical knowledge in this way. I could give many examples of such abuses of Scripture; let two suffice, both relevant to these astronomical questions. The first are the writings which were published attacking the Medicean planets, which I recently discovered, which cited many verses of Scripture to prove that they could not exist.* Now that these planets are plain for everyone to see, I would like to know what new interpretations of Scripture those who opposed me can give to justify their foolishness. The other example I would give is the writer who has recently published a book* arguing, against astronomers and philosophers, that the Moon shines with its own brightness and does not receive its light from the Sun. He confirms—or rather, he persuades himself that he can confirm—this fanciful idea with various passages of Scripture which he thinks make sense only if his opinion is necessary and true. Yet the natural darkness of the Moon is as plain to see as the brilliance of the Sun.
It is clear then that if the authority of these writers had counted for anything, they would have imposed their faulty understanding of Scripture on others and would have made it obligatory to believe as true propositions which run counter to manifest proof and the evidence of the senses. God forbid that such an abuse should ever gain a foothold, for if it did then all the investigative sciences would very soon have to be forbidden; for since there are always far more men who are incapable of properly understanding Scripture and the other sciences than there are men of understanding, they would indulge in their superficial reading of Scripture and claim the authority to pronounce on every question of natural science, on the basis of some verse which they have misunderstood and taken out of the context in which the sacred writers intended it. And they would overwhelm the small number of those who understand such matters, as they would always have more followers, for people will always prefer to gain a reputation for wisdom without the effort of studying than to wear themselves out labouring tirelessly at rigorous scientific disciplines. So we should give thanks to God that in his kindness he has spared us this fear, by denying such people any authority and ensuring that no weight is given to their shallow writings. Rather, the task of consulting, deciding, and legislating on matters of such importance has been entrusted to the wisdom and goodness of prudent Fathers and to the supreme authority of those who, guided by the Holy Spirit, cannot fail to decree wisely. I think that it was against such men that the Church Fathers wrote with well-justified indignation, in particular St Jerome,* who says:
The garrulous old woman, the senile old man, and the long-winded sophist all presume to have their say about Scripture, mangling it and teaching before they have learnt. Some, prompted by pride, bandy fine-sounding words as they hold forth about Holy Writ among ignorant women; others, I am ashamed to say, learn from women what they teach to men, and as if that were not enough, glibly expound to others things that they do not understand themselves. I will not even speak of those of my colleagues who, perhaps having come to the Holy Scriptures after a career in secular letters, gratify people’s ears with carefully constructed phrases, and think that whatever they say is the word of God, without bothering to find out what the prophets and apostles taught. They adapt incongruous testimonies to their own purposes, as if it was an admirable rather than a deplorable way of teaching to distort the meaning of Scripture and twist it to their own contradictory ideas.
There are some theologians whom I hold to be men of great learning and sanctity of life, and for whom I therefore have the highest esteem, whom I would not wish to count among such profane writers. But I must confess that I do have some doubts which I would gladly have resolved when I hear that they claim, on the basis of the authority of Scripture, to require others to accept in scientific debates the view which they consider best harmonizes with Scriptural texts, while at the same time not accepting any obligation on their part to answer the reasons or evidence given to the contrary. They explain and justify this position by saying that theology is the queen of sciences, and therefore should on no account stoop to adapt to the teachings of other less exalted sciences which are subordinate to her, but rather that they should defer to her as the supreme ruler, and change their conclusions to conform to the statutes and decrees of theology. They go further, and say that if those who profess a subordinate science reach a conclusion which they consider to be certain, because it can be demonstrated or proved experimentally, but which is contradicted by a conclusion stated in Scripture, then it is up to them to disprove their own demonstrations and expose the fallacies in their own experiments, without bothering the theologians and biblical scholars. For, they say, it is not befitting the dignity of theology to stoop to investigating the weaknesses of its subject sciences; its role is solely to determine the truth of the conclusion, with absolute authority and in the certainty that it cannot err. The scientific conclusions about which they say we should defer to Scripture, without trying to gloss or interpret it in any way other than the literal meaning of the words, are those where Scripture consistently says the same thing and which the Church Fathers all receive and expound in the same way. There are several points about this ruling which I will raise so as to be advised by those who understand these matters better than me, and to whose judgement I submit at all times.
First, I fear there may be some cause for confusion if the preeminence which entitles theology to be called the queen of sciences is not clearly defined. It could be because the material taught by all the other sciences is encompassed and demonstrated in theology, but by more comprehensive methods and with more profound learning—in the same way as, for instance, the rules for measuring fields or keeping accounts are contained pre-eminently in arithmetic and Euclid’s geometry rather than in the practical methods of surveyors or accountants. Or it could be because the subject matter of theology surpasses in dignity the subject matter of the other sciences, and because it proceeds by more sublime methods. I do not think that theologians who are conversant with the other sciences would claim that theology deserves to be called queen for the first of these reasons, for it is hard to believe that any of them would say that geometry, astronomy, music, and medicine are more comprehensively and precisely expounded in Scripture than in the works of Archimedes, Ptolemy, Boethius, and Galen.* It follows that the regal pre-eminence of theology must be of the second kind, namely on account of its elevated subject matter, its marvellous teaching of divine revelation, which human comprehension could not absorb in any other way, and its supreme concern with how we gain eternal beatitude. And if theology is concerned with the most elevated contemplation of the divine, occupying its regal throne because of its supreme authority, and does not stoop to the baser and more humble concerns of the subordinate sciences but rather, as has been said above, has no interest in them because they do not concern our beatitude, then those who practise and profess it should not claim the authority to lay down the law in fields where they have neither practised nor studied. If they did, they would be like an absolute prince who, knowing he was free to command obedience as he wished, insisted that medical treatment be carried out and buildings be constructed as he dictated even though he was himself neither a doctor nor an architect, thereby causing grave danger to the lives of his unfortunate patients and the evident ruin of his buildings.
Then, to command that professors of astronomy should be responsible for undermining their own observations and proofs as no more than fallacies and false arguments, is to command something quite impossible for them to do. For it amounts to telling them not to see what they see, and not to understand what they understand and, indeed, to find in their research the very opposite of what evidence shows them. If they were to be asked to do this, they would first have to be shown how to make one mental faculty give orders to another, and the lower faculties to command the higher, so that the imagination and the will were made able and willing to believe the opposite of what the intellect understands (in saying this I am still confining myself to purely scientific questions which are not articles of faith, and not to those which are supernatural and articles of faith). So I do beg these most prudent Fathers to consider very carefully the difference between statements which are a matter of opinion and those which can be demonstrated. If they keep in mind the strength of logical deduction, they will better understand why it is not in the power of those who profess the demonstrative sciences to change their opinion at will, applying themselves first to one view then to another, and that there is a great difference between commanding a mathematician or a philosopher and persuading a merchant or a lawyer to change their mind. It is not as easy to change one’s view of conclusions which have been demonstrated in the natural world or in the heavens, as it is to change one’s opinion on what is or is not permissible in a contract, a declaration of income, or a bill of exchange. The Church Fathers understood this very well, as can be seen from the great care they took to refute many arguments, or rather fallacies, in philosophy. This may be found expressly in some of them; in particular, we have the following words of St Augustine:*
It is unquestionable that whatever the sages of this world have demonstrated concerning physical matters, we can show not to be contrary to our Scripture. But whatever they teach in their books that is contrary to Holy Scripture is without doubt wrong and, to the best of our ability, we should make this evident. And let us keep faith in our Lord, in whom are hidden all the treasures of wisdom, so that we will not be led astray by the glib talk of false philosophy or frightened by the superstition of counterfeit religion.
From these words, it seems to me, the following principle can be derived: that the writings of secular scholars contain some statements about the natural world which are demonstrably true, and others which are simply asserted. As regards the former, it should be the task of wise theologians to show that they are not contrary to Scripture; and as regards the latter—those which are stated but not conclusively demonstrated—if there is anything in them which is contrary to Scripture, they should be regarded as undoubtedly false, and their falseness should be demonstrated by all possible means. Now if scientific conclusions which are demonstrated to be true should not be made subordinate to Scripture, but rather the text of Scripture should be shown not to be contrary to such conclusions, it follows that before a scientific statement is condemned it must be shown that it has not been conclusively demonstrated. And the responsibility for showing this must lie not with those who uphold its truth but with those who believe it to be false: this is only reasonable and natural, for it is much easier for those who do not believe a statement to identify its weaknesses than for those who believe it to be true and conclusive. Indeed, the upholders of an opinion will find that the more they go over the arguments, examining their logic, replicating their observations, and comparing their experiments, the more they will be confirmed in their belief. Your Highness knows what happened when the former mathematician at the University of Pisa* undertook in his old age to examine the teaching of Copernicus, in the hope of finding grounds for refuting it (for he was secure in his conviction that it was false as long as he had not read it): as soon as he grasped the foundations, the logic, and the demonstrations of the argument he became convinced by it, and from being an opponent of Copernicus’ theory he became its staunch supporter. I could also name other mathematicians* who, prompted by my latest discoveries, have acknowledged it necessary to change the accepted system of the world, as it was now completely unsustainable.
If all that was needed to suppress this theory and its teaching was simply to gag a single author, as seems to be the impression of those who, measuring other people’s judgement by the standards of their own, cannot believe that it could continue to find supporters, this would be easily done. But the reality is quite different. To achieve such an effect it would be necessary not just to ban Copernicus’ book and those of the other authors who have followed his teaching, but to forbid the whole science of astronomy itself. More than that, they would have to forbid men to look at the sky, lest they should see Mars and Venus varying so much in their distance from the Earth that Venus appears forty times, and Mars sixty times, larger at some times than at others. Or they would have to prevent them from seeing Venus appear sometimes round and sometimes crescent-shaped with very fine horns, and many other observations of the senses which are completely incompatible with the Ptolemaic system, but provide solid evidence for the Copernican one. To ban Copernicus’ book now, when many new observations and the work of many scholars who have read it are establishing the truth of his position and the soundness of his teaching more firmly every day, and after allowing it to circulate freely for many years when it had few followers and less evidence to support it, would in my view seem to be a contravention of the truth. It would be trying all the harder to conceal and suppress it the more it is plainly and clearly demonstrated. Not to ban the whole book, but just to condemn this particular proposition as false, would, if I am not mistaken, be even more harmful to people’s souls, for it would allow them to see the proof of a proposition which they were then told it was sinful to believe. And to forbid the whole science of astronomy would be nothing less than contradicting a hundred passages of Holy Scripture, which teach us that the glory and greatness of God is wonderfully revealed in all his works, and made known divinely in the open book of the heavens.* Nor should anyone think that the lofty concepts which are to be found there end in simply seeing the splendour of the Sun and the stars in their rising and setting, which is as far as the eyes of brutes and the common people can see. The book of the heavens contains such profound mysteries and such sublime concepts that all the burning of midnight oil, all the labours, and all the studies undertaken by hundreds of the most acute minds have still not fully penetrated them, even after investigations which have continued for thousands of years. So let even the ignorant recognize that, just as what their eyes see when they look at the external appearance of the human body is as nothing compared to the marvellous complexity which is apparent to the trained and dedicated anatomist and philosopher, who never ceases to be amazed and delighted as he investigates the uses of the muscles, tendons, nerves, and bones, or when he examines the functions of the heart and the other principal organs, seeking out the seat of the vital faculties, observing the wonderful structure of the sensory organs, and contemplating where the imagination, the memory, and the power of reason dwell—in the same way, the heavens as they appear to the naked eye are as nothing compared to the great wonders which, through long and painstaking observations, the minds of intelligent men can discern there. This concludes what I have to say on this point.
Next let us answer those who assert that those scientific propositions of which Scripture consistently says the same thing, and which the Church Fathers have all received in the same way, should be understood according to the bare meaning of the words, without trying to gloss or interpret them, and should be accepted and believed as absolutely true; and that the motion of the Sun and the fixity of the Earth are such propositions and are therefore to be believed as matters of faith, and the contrary opinion is to be considered an error. On this I would make the following observations. First, there are some scientific propositions about which human speculation and reason cannot arrive at securely demonstrated knowledge, but can only supply a probable opinion and a reasonable conjecture—such as, for example, whether the stars are animate beings. There are other propositions of which we have, or can confidently expect to have certain knowledge, by means of experiment, prolonged observation, and necessary demonstrations; such are the questions whether the Earth or the Sun moves, or whether the Earth is a sphere. As far as the first kind of proposition is concerned, I have no doubt that where human reason cannot reach, and where consequently we cannot have certain knowledge but only an opinion or belief, we ought reverently to submit to the pure meaning of Scripture. But as regards the others, I believe that, as I have said above, we must first be certain of the facts, which will reveal to us the true meaning of the Scriptures, which will undoubtedly prove to be in agreement with the demonstrated facts, even if the surface meaning of the words appears to suggest otherwise; for two truths can never contradict each other. This principle seems to me all the more sound and secure because I find it stated in as many words by St Augustine. Writing specifically about the shape of the heavens and what should be believed about it, since astronomers who say that it is round appear to contradict Scripture which states that the heavens are stretched out like a skin,* he says that there is no reason to be concerned if Scripture contradicts the astronomers. The authority of Scripture is to be believed if what they say is false and founded only on fallible human conjecture; but if what they affirm is proved by incontrovertible arguments, he does not say that the astronomers are to be ordered to undermine their own proofs and declare their conclusions to be false. Rather, he says that when Scripture describes the heavens as being like a skin it must be shown that this is not contrary to what the astronomers have demonstrated to be true. These are his words:
But someone may ask: ‘Is not Scripture opposed to those who hold that heaven is spherical, when it says, “who stretches out the heavens like a skin”?’ It does oppose Scripture if their statement is false, for the truth is rather in what God reveals than in what groping men surmise. But if they are able to establish their position with proofs that cannot be denied, we must show that what is said about the skin is not opposed to the truth of their conclusions.*
He goes on to warn us that we should be no less careful to harmonize a passage of Scripture with a demonstrated scientific truth, as with another passage of Scripture which appears to state the opposite. Indeed, I think we should admire the prudence with which this saint, even when he is dealing with difficult questions about which we may be sure that no certain knowledge can be arrived at by human proof, is very cautious about laying down what should be believed. This is what he says at the end of the second book On the Literal Meaning of Genesis, on the question of whether we should believe the stars to be animate:
Although this problem at present is not easy to solve, yet I believe that in the course of our study of Scripture we may come across relevant passages that will enable us to treat the matter according to the rules for interpreting Holy Scripture and arrive at some conclusion that may be held without perhaps demonstrating it as certain. Meanwhile we should always observe that restraint that is proper to a devout and serious person and not rashly believe something about an obscure point. Otherwise, if the truth later becomes known we might despise it because of our attachment to our error, even if what is said is in no way opposed to the sacred writings of the Old or the New Testament.*
From this and from other passages it seems to me, if I am not mistaken, that the view of the Church Fathers was that on questions of natural science which are not matters of faith, we should first consider whether they have been demonstrated beyond doubt or are known from the evidence of the senses, or whether such certain knowledge is possible. If it is, and since this too is a gift of God, we should apply ourselves to understanding the true meaning of Scripture in those places where it appears to state the opposite. Wise theologians will undoubtedly be able to penetrate its true meaning, together with the reasons why the Holy Spirit should sometimes have chosen to veil it under words signifying something different, either to test us or for some other reason which is hidden from me.
As for the point about Scripture consistently saying the same thing, I do not think that this should undermine this principle, if we consider the primary intention of Scripture. If it was necessary on one occasion for Scripture to pronounce on a proposition with words conveying a different sense from its true meaning, as a concession to the understanding of the masses, then why might it not have done the same, and for the same reason, whenever the same proposition was mentioned? Indeed, to do otherwise would only have added to people’s confusion and undermined their readiness to believe. Regarding the state of rest or motion of the Sun and the Earth, experience plainly shows that it was necessary for Scripture to state what its words appear to say; for even in our own time, people far less primitive still maintain the same opinion, for reasons which on careful consideration and reflection will be found to be wholly trivial, and on experiences which are either erroneous or completely irrelevant. And there is no point in even trying to persuade them to change their view, since they are not capable of understanding the arguments against it, depending as these do on observations which are too precise, proofs which are too subtle, and abstractions which require too much power of imagination for them to comprehend. So even if the fixity of the Sun and the motion of the Earth were established and demonstrated with absolute certainty among the wise, it would still be necessary to uphold the opposite to maintain one’s credibility among the vast number of the masses. For if you were to quiz a thousand men among the common people about their view of this matter, I doubt whether you would find one who did not declare himself firmly convinced that the Sun moves and the Earth stands still. But no one should take this almost universal popular consent as an argument for the truth of what they assert; for if we were to question these same men about their grounds and reasons for believing as they do, and on the other hand to listen to the experiments and proofs which have led a few others to believe the opposite, we would find that the latter are persuaded by solidly based reasons, while the former are influenced by shallow appearances and vain and ridiculous comparisons.
It is clear, then, that it was necessary to attribute movement to the Sun and rest to the Earth so as not to confuse the limited understanding of the masses, making them stubborn and reluctant to believe in the principal articles which are absolutely matters of faith; and if this was necessary, then it is not surprising that it was done, with great prudence, in Holy Scripture. I would go further, and say that it was not only consideration for the incomprehension of the masses but the prevailing opinion at that time which led the scriptural writers to accommodate themselves, in matters not necessary to salvation, more to received opinion than to the essential truth of the matter. Speaking of this, St Jerome writes,* ‘as if there were not many things in the Holy Scriptures that were said according to the opinion of the time when they took place, rather than according to the truth contained’; and elsewhere,* ‘It is the practice in the Scriptures for the writer to give the view of things as they were universally believed at that time.’ And St Thomas, commenting on the words in Job chapter 27,* ‘He stretches out the north over the void, and hangs the earth upon nothing’, notes that Scripture refers to the space which enfolds and surrounds the Earth as ‘void’ or ‘nothing’, while we know that it is not empty but full of air. Nonetheless, he says, Scripture adapts to the view of the masses, who believe this space to be empty, by calling it ‘void’ and ‘nothing’. In St Thomas’s own words,* ‘What seems to us in the upper hemisphere of the sky to be nothing but space filled with air, the common people consider to be empty; and Holy Scripture speaks of it according to the belief of the common people, as is its wont.’ From this example I think it can clearly be deduced that on the same principle, holy Scripture had all the more reason to refer to the Sun as in motion and the Earth at rest; for if we challenge the common people’s understanding, we will find them much more resistant to the idea that the Sun is at rest and the Earth in motion than to the space around us being full of air. So, if the Scriptural authors refrained from trying to convince the common people even of a point about which they could be persuaded relatively easily, it seems only reasonable that they should have followed the same policy in other much more difficult questions.
Copernicus himself recognized how much our imagination is influenced by ingrained habit and by ways of conceiving things which have been familiar to us since childhood; so in order not to make these abstract ideas even more confusing and difficult for us, once he had demonstrated that the movements which appear to us to belong to the Sun and the firmament are actually movements of the Earth, he continued to call them movements of the Sun and the heavens when he came to set them down in tables and show how they worked in practice. So he talks about the rising and setting of the Sun and the stars, of changes in the inclination of the zodiac and variations in the equinoctial points, of the mean motion, anomalies, and prosthaphaeresis of the Sun,* and so on. All these are in fact movements of the Earth; but since we are on the Earth and hence share in its every motion, we cannot discern them in the Earth directly, but have to refer them to the heavenly bodies where they appear to be. Hence we speak of them as if they occurred where we perceive them to be. This shows how natural it is to adapt ourselves to our habitual way of seeing things.
As for saying that when the Church Fathers agree in interpreting a statement in Scripture on a matter of natural science in the same way this should give it such authority that it becomes a matter of faith to believe it, I think that this should apply at most to those conclusions which the Fathers have aired and discussed exhaustively, weighing up the arguments on both sides before all agreeing that one view should be upheld and the other condemned. But the motion of the Earth and the fixity of the Sun are not propositions of this kind, for such an opinion was completely buried and far removed from the questions discussed by scholars at that time, and was not even considered, let alone upheld, by anyone. So it is fair to assume that it never occurred to the Fathers to discuss the matter, since Scripture, their own views, and the common consent of everyone all agreed on the same opinion, without anyone thinking to contradict it. So it is not enough to say that because the Fathers all accept the fixity of the Earth, etc., this is to be believed as an article of faith; it must be proved that they condemned the contrary opinion. For I could always say that as they never had any occasion to reflect on the matter or to discuss it, they simply left it and accepted it as the current opinion, not as something which had been resolved and established. Indeed, I think I have firm grounds for saying this; for either the Fathers reflected on this as a matter of controversy, or they did not. If they did not, then they cannot have reached any judgement about it, even in their own minds, and their indifference to it should not place any obligation on us to accept precepts which they did not even consider imposing. If on the other hand they had turned their minds to it and considered it, they would already have condemned it if they had judged it to be erroneous, and there is no record of their having done so. Indeed, once some theologians began to consider the matter, it is clear that they did not deem it to be erroneous: Didachus of Stunica,* for instance, in his Commentaries on Job, chapter 9, verse 6, commenting on the words ‘Who shakes the earth out of her place’, etc., discusses the Copernican position at length and concludes that the motion of the Earth is not contrary to Scripture.
I have, in any case, some reservations about the truth of the claim that the Church requires us to believe as articles of faith such conclusions in natural science as are supported solely by the common interpretation of the Church Fathers. I wonder whether those who argue in this way may have been tempted to extend the scope of the Conciliar decrees in support of their own opinion; for the only prohibition I can find on this matter is against distorting in a sense contrary to the teaching of the Church and the common consent of the Fathers those passages, and those alone, which concern matters of faith or morals or the building up of Christian doctrine. This is what was stated by the Council of Trent in its fourth Session.* But the motion or fixity of the Earth or the Sun are not matters of faith or morals, and no one is trying to distort the meaning of Scripture in ways contrary to the teaching of the Church or the Fathers. In fact those who have written about this matter have never cited passages of Scripture, leaving it to the authority of wise and learned theologians to interpret these passages according to their true meaning. It is clear that the Conciliar decrees agree with the Church Fathers in this respect; indeed, so far are they from making such scientific questions articles of faith and condemning contrary opinions as erroneous that they consider it pointless to try to arrive at certainty in such matters, preferring rather to concern themselves with the primary intention of the Church. Let your Highness hear what St Augustine says in response to those Christians who ask whether it is true that the heavens move or whether they are at rest:
My reply is that it would require a great deal of subtle and learned enquiry into these questions to arrive at a true view of the matter. I do not have the time to go into these questions and nor have those whom I wish to instruct for their own salvation and for what is necessary and useful in the Church.*
But even if it were resolved to condemn or admit propositions in natural science according to passages of Scripture which have been unanimously interpreted in the same way by all the Church Fathers, I do not see that this would apply to the present case, for the Fathers differ in their interpretation of the same passages. Dionysius the Areopagite* says that it was not the Sun but the Primum Mobile which stood still. St Augustine is of the same opinion, namely that all the celestial bodies came to a stop; so too is the Bishop of Avila.* But there are Jewish writers, cited with approval by Josephus, who maintain that the Sun did not really stand still, but only seemed to because the Israelites took so little time to defeat their enemies. Similarly with the miracle at the time of Hezekiah, Paul of Burgos* says that it was not the Sun that moved but the sundial.* But in any case, I will show below that it is necessary to gloss and interpret the meaning of the text of the book of Joshua regardless of the view we take of the structure of the universe.
But let us finally concede to these gentlemen more than they ask, and submit entirely to the judgement of wise theologians; and since there is no record of this particular debate being conducted by the ancient Fathers, let it be undertaken by the wise men of our own age. After hearing the experiences, the observations, the arguments, and the proofs cited by philosophers and astronomers on both sides—for it is a controversy over problems of natural science and logical dilemmas, in which a decision has to be made one way or the other—they will be able to determine the matter positively as divine inspiration dictates. But as for those who are ready to risk the majesty and dignity of Holy Scripture for the sake of defending their own vain imagination, let them not hope that such a resolution as this is to be reached without establishing the facts with certainty and discussing in detail all the reasons on both sides of the argument; nor need those who seek only that the foundations of this teaching should be carefully considered, prompted purely by a holy zeal for the truth, for Scripture, and for the majesty, dignity, and authority in which all Christians are bound to uphold it, have anything to fear from such a procedure. Surely it is plain to see that this dignity is far more zealously sought and secured by those who submit wholeheartedly to the Church, without asking for one or other opinion to be prohibited but only that they should be allowed to bring matters forward for discussion so that the Church can reach a decision with greater confidence, than by those who, blinded by their own self-interest or prompted by the malicious suggestions of others, preach that the Church should wield its sword straight away simply because it has the power to do so? Do they not realize that it is not always beneficial to do what one has power to do? This was not the view of the Church Fathers; on the contrary, they knew how prejudicial and how contrary to the primary intention of the Catholic Church it would be to use verses of Scripture to establish scientific conclusions which experience and necessary demonstrations might in time show to be contrary to the literal meaning of the text. Hence they not only proceeded with great caution, but they also left the following precepts for the guidance of others:
In matters that are obscure or far from clear, if we should read anything in Holy Scripture that may allow of different interpretations that are consistent with the faith we have received, we should not rush in headlong and so firmly commit ourselves to one of these that, if further progress in the search of truth justly undermines this position, we too fall with it. That would be to battle not for the meaning of Holy Scripture but for our own, by wanting something of ours to be the meaning of Scripture rather than wanting the meaning of Scripture to be ours.*
A little further on, to teach us that no proposition can be contrary to the faith if it has not first been shown to be false, he adds: ‘Nothing is contrary to the faith until unerring truth gives the lie to it. And if that should happen, it was never taught by Holy Scripture but stemmed from human ignorance.’ It is clear from this that any view which we attributed to a passage of Scripture would be false if it did not agree with demonstrated truth. Therefore we should use demonstrated truth to help us discover the correct meaning of Scripture, and not try to force nature or deny the evidence of experience and necessary demonstrations in order to conform to the literal meaning of the words, which our imperfect understanding might think to be true.
But note further, your Highness, how carefully this great saint proceeds before affirming that a particular interpretation of Scripture is correct, and so firmly established that there need be no fear of encountering any difficulty which might undermine it. Not content that a reading of Scripture should agree with a demonstrated truth, he adds:
But when some truth is demonstrated to be certain by reason, it will still be uncertain whether this sense was intended by the sacred writer when he used the words of Holy Scripture, or something else no less true. And if the general drift of the passage shows that the sacred writer did not intend this sense, the other, which he did intend, will not thereby be false. Indeed, it will be true and more worth knowing.
Yet this author’s caution is even more remarkable when, not being convinced after seeing the demonstrations, the literal meaning of Scripture, and the context of the passage as a whole all pointing to the same interpretation, he adds: ‘But if the context supplies nothing to disprove this to be the mind of the writer, we still have to enquire whether he may not have meant the other as well.’ Not even then resolving to accept one interpretation and reject the other, he seems to think he can never be cautious enough, for he goes on: ‘But if we find that the other also may be meant, it will not be clear which of the two meanings he intended. And there is no difficulty if he is thought to have wished both interpretations if both are supported by clear indications in the context.’ Finally, he justifies this rule of his by showing the dangers to which Scripture and the Church are exposed by those who, being more interested in maintaining their own error than in upholding the dignity of Scripture, seek to extend the authority of Scripture beyond the terms which Scripture itself prescribes. He adds the following words, which alone should suffice to restrain and moderate the excessive licence which some claim for themselves:
It often happens that a non-Christian knows something about the earth, the heavens, and the other elements of this world, about the motion and orbit of the stars and even their size and relative positions, about the predictable eclipses of the Sun and Moon, the cycles of the years and the seasons, about the kinds of animals, shrubs, stones, and so forth, and this knowledge he holds to as being certain from reason and experience. Now, it is a disgraceful and dangerous thing for an infidel to hear a Christian, presumably giving the meaning of Holy Scripture, talking nonsense on these topics. We should take all means to prevent such an embarrassing situation in which the non-believer will scarce be able to contain his laughter seeing error written in the sky, as the proverb says. The shame is not so much that an ignorant individual is derided, but that people outside the household of the faith think our writers hold such opinions, and criticize and reject them as ignorant, to the great prejudice of those whose salvation we are seeking. When they find a Christian mistaken in a field which they themselves know well and hear him maintaining foolish opinions about our books, how are they going to believe those books in matters concerning the resurrection of the dead, the hope of eternal life, and the kingdom of heaven, when they think their pages are full of falsehoods about things which they themselves have learnt from experience and decisive argument?
This same saint shows how much the truly wise and prudent Fathers are offended by those who try to uphold propositions which they do not understand by citing passages of Scripture, compounding their original error by producing other passages which they understand even less than the first; he writes:
Rash and presumptuous men bring untold trouble and sorrow on their wiser brethren when they are caught in one of their false and unfounded opinions and are taken to task by those who are not bound by the authority of our sacred books. For then, to defend their utterly reckless and obviously untrue statements, they call upon Holy Scripture, and even recite from memory passages which they think support their position, although they understand neither what they mean nor to what they properly apply.
This seems to me to describe exactly those who keep citing passages of Scripture because they are unable or unwilling to understand the proofs and experiments which the author of this doctrine and his followers advance in its support. They do not realize that the more passages they cite and the more they insist that their meaning is perfectly clear and cannot possibly admit any other interpretation than theirs, the more they would undermine the dignity of Scripture (if, that is, their opinions carried any weight) if the truth were then clearly shown to contradict what they say, causing confusion at least among those who are separated from the Church and whom the Church, like a devoted mother, longs to bring back to her bosom. So your Highness can see how flawed is the procedure of those who, in debating questions of natural science, give priority in support of their arguments to passages of Scripture—and often passages which they have misunderstood.
But if they really believe and are quite certain that they possess the true meaning of a particular text of Scripture, they must necessarily be convinced that they hold in their hand the absolute truth of the scientific conclusion which they intend to debate, and so must know that they have a great advantage over their opponent who has to defend what is false. The one who is defending the truth will be able to draw on numerous sensory experiences and necessary demonstrations to support their position, while their opponent has to fall back on deceptive appearances, illogical reasoning, and fallacies. Why then, if they are so confident that their purely scientific and philosophical weapons are so much stronger in every way than their adversary’s, do they immediately have recourse, as soon as battle is joined, to an awesome and irresistible weapon the very sight of which strikes terror into the heart of their opponent? If the truth be told, I believe that they are the first to be terror-struck, and that when they realize they are unable to resist the assaults of their adversary they try to find a way of not letting him come near them. To that end they forbid him to use the gift of reason which the divine goodness has granted him, and abuse the right and proper authority of Scripture which by common consent of theologians, if it is understood and used properly, can never contradict the evidence of plain experience and necessary demonstrations. But I do not think that their resorting to Scripture to cover up their inability to understand, let alone to answer, the arguments against them will do them any good, since this opinion has never hitherto been condemned by the Church. So if they wish to deal honestly they should either confess by their silence that they are unqualified to discuss such matters, or they should first consider that it is not in their power or that of anyone except the Supreme Pontiff or the Councils of the Church to declare a proposition to be erroneous, although they do have the right to debate whether it is true or false. Then, since it is impossible for any proposition to be both true and heretical, they should concern themselves with what they are entitled to discuss, namely demonstrating that it is false. Once they have established its falsehood, either there will be no more need to prohibit it because no one will subscribe to it, or it can safely be prohibited without any risk of causing scandal.
So let these people first apply themselves to refuting the arguments of Copernicus and others, and leave condemning his view as erroneous and heretical to those who have the authority to do so; but let them not hope to find in the wise and cautious Fathers of the Church or in the absolute wisdom of the One who cannot err those hasty judgements into which they are sometimes drawn by their own desires or vested interests. No one doubts that the Supreme Pontiff always has absolute power to admit or to condemn these and similar propositions which are not directly articles of faith; but it is beyond the power of any created being to make them true or false, in defiance of what they are de facto by their own nature. So they would be better advised first to establish with certainty the necessary and immutable truth of the matter, over which no one has any control, than to condemn either side in the absence of any such certainty. This would only deprive them of their own authority and freedom to choose, by imposing necessity on matters which at present are undetermined and a subject of free choice but still reserved to the authority of the Supreme Pontiff. In short, if it is not possible for a conclusion to be declared heretical while there is still uncertainty over whether it may be true, it is a waste of time for anyone to clamour for the condemnation of the motion of the Earth and the fixity of the Sun before they have demonstrated that such a position is impossible and false.
It remains finally for us to consider how far the passage in Joshua can be taken in the straightforward literal meaning of the words, and how it could come about that the day was much prolonged when the Sun obeyed Joshua’s command to stand still.
If the movements of the heavens are taken according to the Ptolemaic system, such a thing cannot happen. For the Sun moves through the ecliptic in the order of the signs of the zodiac, that is, from west to east, and hence in the opposite direction to the motion of the Primum Mobile,* which is from east to west, this being the motion which produces day and night. It is clear therefore that if the Sun were to cease its own proper motion, the effect would be to make the day shorter, not longer. The way to make the day longer would be to speed up the Sun’s motion; for to make the Sun remain at the same point above the horizon for some time without declining towards the west, its motion would have to be speeded up until it equalled that of the Primum Mobile, which would be about 360 times its normal speed. So if Joshua had meant his words to be taken in their strictly literal sense, he would have commanded the Sun to speed up its motion so that the Primum Mobile ceased to carry it along towards its setting. But since his words were heard by people whose knowledge of the motions of the heavens was very likely confined to just the universally known movement from east to west, and since he had no intention of teaching them about the structure of the spheres but only that they should comprehend the great miracle of prolonging the day, he adapted his words to their understanding and spoke in the way which would make sense to them.
Perhaps it was this consideration which prompted Dionysius the Areopagite to say* that the miracle consisted in stopping the Primum Mobile, with the consequence that all the other celestial spheres also stood still; St Augustine himself is of the same opinion,* and the Bishop of Avila also confirms it at length.* Indeed, it is clear that Joshua’s intention was to make the whole system of celestial spheres stand still, because his command also included the Moon even though the Moon had nothing to do with prolonging the day. By commanding the Moon he implicitly included all the other planets, which are not named here any more than they are elsewhere in Scripture, since it has never been the intention of Scripture to teach us the science of astronomy.
It seems clear to me, therefore, if I am not mistaken, that if we were to accept the Ptolemaic system, we would have to interpret the words of Scripture in a sense different from their literal meaning; but bearing in mind the salutary warnings of St Augustine, I do not say that this is necessarily the correct interpretation, as someone else might come up with a better and more appropriate one. I would, however, like to conclude by asking whether this passage can be understood in a sense closer to what we read in Joshua if we assume the Copernican system, together with a further observation which I have recently made concerning the body of the Sun. I put forward this suggestion always with the reservation that I am not so wedded to my own ideas as to claim they are superior to other people’s, or to deny that better interpretations may be forthcoming which would conform more closely to the intention of Holy Scripture.
Let us assume, then, in the first place, that the miracle in the book of Joshua meant bringing the whole system of celestial revolutions to a standstill, as suggested by the authors quoted above; this is because if just one sphere were to stand still it would upset the whole system, introducing unnecessary disruption throughout the whole of nature. Secondly, I take into account that the body of the Sun, while remaining fixed in the same place, nonetheless turns on its own axis, completing one revolution in about a month, as I believe I have demonstrated in my Letters on the Sunspots.* We can observe this movement and see that in the upper part of the Sun’s globe it is inclined towards the south, and therefore in the lower part it inclines towards the north—in just the same manner as all the revolutions of the planets. Thirdly, if we consider the nobility of the Sun and the fact that it is the source of light, not only for the Moon and the Earth but, as I show conclusively, also for all the other planets, all of which similarly have no light of their own, I think it is not unreasonable to suggest that the Sun, as the chief minister of nature and, in a sense, the heart and soul of the universe, dispenses not only light to the bodies which surround it but also motion, by virtue of its turning on its own axis. This means that, just as if an animal’s heart stopped beating all the other parts of the body would also stop moving, so if the rotation of the Sun were to cease, the rotations of the planets would stop as well. Of the many weighty writers I could cite to confirm the wonderful strength and power of the Sun, let it suffice for me to quote one passage from the blessed Dionysius the Areopagite in his book On the Divine Names.* Writing of the Sun, he says: ‘His light also gathers and converts to itself all the things that are seen, moved, lighted, or heated, in a word everything that is held together by its splendour. Therefore the Sun is called Helios, for it gathers and brings together everything that is scattered.’ A little later he goes on to say,
This Sun which we see is one, and although the essences and qualities of those things that we perceive with our senses are many and varied, yet the Sun sheds its light equally on all things, and renews, feeds, protects, completes, divides, unites, fosters, makes fruitful, increases, changes, fixes, builds up, moves, and gives life to them all. Every single thing in this universe, inasmuch as it can, partakes of one and the same Sun, and the causes of many things which partake of it are equally anticipated in it; and for all the more reason, etc.
So, the Sun being the source of both light and motion, if God wished that at Joshua’s command the whole system of the world should rest and remain for several hours in the same state, it sufficed to make the Sun stand still. When the Sun stopped, all the other revolutions stopped as well; the Earth, Moon, and Sun remained in the same relationship to each other, as did all the other planets; and as long as this continued the day did not decline towards night, but was miraculously prolonged. In this way, by stopping the Sun it was possible to prolong the day on Earth, without altering or disrupting the other aspects and mutual positions of the stars, which agrees perfectly with the literal sense of the sacred text.
Another point which, if I am not mistaken, is of no small significance, is that the Copernican system makes another detail in the literal account of this miracle perfectly clear: namely, that the Sun stood still ‘in the midst of the heavens’. This passage has caused learned theologians some difficulty, because it seems likely that when Joshua prayed for the day to be prolonged it was already near to sunset, not at midday—for if it had been at midday, and given that this happened about the time of the summer solstice when the days are at their longest, it seems unlikely that he would have needed to pray for the day to be prolonged so that he could pursue the battle to victory; the seven hours or more of daylight which remained would have been more than enough. So some very learned theologians have concluded that it must have been near to sunset; and indeed this is implied by Joshua’s words, ‘Sun, stand still’, since if it had been at midday, either he would not have needed to ask for a miracle or it would have been enough to pray for the Sun to slow down. This is the view of Cajetan,* to which Magalhães* also subscribes, and confirms it by pointing out that Joshua had already done so many other things that day before he commanded the Sun that he could not possibly have completed them all in half a day. So they are reduced to interpreting the words ‘in the midst of heaven’ in a somewhat forced way, saying that they simply mean the Sun stopped when it was in our hemisphere, that is, when it was above the horizon. But I think we can avoid this and any other forced reading if we follow the Copernican system and place the Sun ‘in the midst’, that is, in the centre of the heavenly orbs and the revolutions of the planets, as indeed we must. Then, regardless of the time of day, whether at midday or at any other time towards evening, the day was prolonged and the revolutions of the heavens stood still when the Sun stopped in the midst of heaven, that is, in the centre, where it belongs. Apart from anything else, this is a more natural reading of the literal sense of the text, for if the writer had wanted to say that the Sun stood still at noon it would have been more correct to say that it ‘stood still at midday, or in the circle of the meridian’, not ‘in the midst of heaven’. For the only true ‘midst’ of a spherical body like the sky is its centre.
As for other passages of Scripture which appear to contradict the Copernican position, I have no doubt that, if this position were once known to be true and proven, those same theologians who now, believing it to be false, find such passages incapable of being interpreted in a way compatible with it, would find interpretations for them which would accord with it very well, especially if their understanding of Holy Scripture were combined with some knowledge of astronomy. Just as now, believing this position to be false, they read the Scriptures and find only passages which conflict with it, so if they once entertained a different view of the matter they might well find just as many others which agreed with it. Then they might judge it fitting for the Holy Church to proclaim that God placed the Sun in the centre of the heaven and, by turning it on its axis like a wheel, gave the Moon and the other wandering stars their appointed course, when she sings the hymn:*
O God, whose hand hath spread the sky,
and all its shining hosts on high,
and painting it with fiery light,
made it so beauteous and so bright:
Thou, when the fourth day was begun,
didst frame the circle of the sun,
and set the moon for ordered change,
and planets for their wider range.
They could also say that the word ‘firmament’ is literally correct for the starry sphere and for everything which is beyond the revolutions of the planets, for in the Copernican system this is totally firm and immobile. And since the Earth moves in a circle, when they read the verse, ‘Before he had made the Earth and the rivers, and the hinges of the earth’,* they might think of its poles, for it seems pointless to attribute hinges to the terrestrial globe if it does not turn on its axis.
To the Very Reverend Father Paolo Antonio Foscarini,* Provincial of the Carmelites of the Province of Calabria.
Very Reverend Father,
I was pleased to read the letter in Italian and the essay in Latin which you sent me. They are full of insight and learning, and I thank you for them both. As you ask for my opinion I will reply very briefly, as at present you have little time for reading and I for writing.
First, it seems to me that both you and signor Galileo are acting prudently in confining yourselves to speaking hypothetically and not in absolute terms, as I have always understood Copernicus to have done. It is perfectly proper, and poses no danger, to say that all the appearances are saved* more effectively by the hypothesis that the Earth moves and the Sun is fixed than by postulating eccentrics and epicycles; and this is as far as a mathematician can go. But to say that the Sun actually is at the centre of the universe, that it turns on its axis but does not move from east to west, and that the Earth is in the third heaven and moves at a great speed around the Sun—this incurs a great danger, not only of provoking all scholastic philosophers and theologians, but also of undermining the faith by suggesting that Holy Scripture is in error. For while you have shown many ways in which Scripture can be expounded, you have not applied these to particular cases, and there is no doubt that you would have had great difficulty if you had tried to expound all the passages which you yourself cited.
Second, as you know, the Council forbids expounding the Scriptures in ways contrary to the common consent of the Church Fathers; and if you read not just the Fathers but also modern commentators on Genesis, the Psalms, Ecclesiastes, and Joshua, you will find that they all agree in interpreting the text literally when it says that the Sun is in the heavens and revolves at great speed around the Earth, and that the Earth is immobile at the centre of the universe, at a very great distance from the heavens. So consider now, in all prudence, whether the Church can allow the Scriptures to be interpreted in a way contrary to the Fathers and to all the Greek and Latin expositors. And it is no response to say that this is not an article of faith, because even if the subject matter is not an article of faith, the authority of the speaker is. It would be just as heretical to deny that Abraham had two sons and that Jacob had twelve, as it would be to deny that Christ was born of a virgin, for both are declared by the Holy Spirit speaking through the mouths of the prophets and apostles.
Third, if it were demonstrated to be true that the Sun is at the centre of the universe and the Earth is in the third heaven, and that the Earth goes round the Sun and not the Sun round the Earth, then we would have to consider very carefully how to interpret the Scriptures which appear to state the contrary; and rather than declare a demonstrated truth to be false, we would have to say that we do not understand them. But I will not believe that such a demonstration exists until it is shown to me. To demonstrate that the appearances are saved by the hypothesis that the Sun is at the centre and the Earth is in the heavens, is not the same as demonstrating that the Sun really is at the centre and the Earth in the heavens. I believe that the first can be demonstrated, but I have very great doubts about the second; and where there is doubt we should not abandon the Holy Scriptures as they have been expounded by the Fathers. I will add that it was Solomon who wrote ‘The Sun also rises, and the Sun goes down, and hastens to the place where it rises’, etc.,* and that Solomon, quite apart from being inspired by God, was a man wiser than all others and most learned in all human sciences and the knowledge of the created world. All his wisdom came from God, so it does not seem likely that he would affirm something which is contrary to demonstrated or demonstrable truth. It may be objected that Solomon was speaking according to appearances, and that the Sun appears to us to be revolving in the heavens when in fact it is the Earth that is revolving, in the same way as it appears to someone on a ship moving away from the shore that it is the shore that is moving away from the ship.* To this I would reply that someone sailing away from the shore, even if the shore appears to be moving away from them, knows that this is an error and corrects it, as they can clearly see that the ship is moving and not the shore; but as far as the Sun and the Earth are concerned, no wise man has ever needed to correct the error, because he clearly perceives that the Earth is not moving and that his eyes do not deceive him when he judges the Sun to be moving, in the same way as he does not err when he judges the Moon and the stars to be moving. So let this suffice for now.
With this, Reverend Father, I send cordial regards to you, and pray that God may grant you every contentment.
From my residence, 12 April 1615.
As a brother,
Cardinal Bellarmine
In order to remove, as far as God grants me, any obstacle which might deflect those charged with adjudicating in the present controversy from reaching a correct judgement, I shall try to eliminate two notions which some people appear to me to be trying to impress on them, both of which, if I am not mistaken, are at variance with the truth.
The first is that there is no reason to fear that their judgement might cause a scandal; for they say that the fixity of the Earth and the motion of the Sun are so well established in philosophy that they can be regarded as absolutely secure and certain, and that to assert the contrary is such an immense paradox and so patently foolish that there is no reason to fear that it might be demonstrated, or even countenanced by any person of sound judgement, either now or at any time in the future. The other notion which they are trying to establish is that, while Copernicus or other astronomers have taken the contrary view, they have done so purely hypothetically, as better preserving the appearances of the motions of the heavens and the calculations and computations of astrologers,* and that even those who advance this hypothesis do not believe it to be factually true in nature; hence they conclude that it can safely be condemned. I believe that this argument is fallacious and at variance with the truth, as I shall make clear in the following observations, which are of a general nature and such as can be understood without great difficulty or study even by those who are not expert in the natural sciences and astronomy. Should the occasion arise to discuss these points with those who are well versed in these subjects, or at least have the time to consider them with the application that the difficulty of the material requires, I would recommend simply that they read Copernicus’ book itself, and the strength of its demonstrations will clearly reveal the truth or falsehood of the two notions we are discussing.
That this is not a view to be dismissed as ridiculous is clear, then, from the many distinguished men, ancient as well as modern, who have held it in the past and who hold it today. Anyone who considered it ridiculous would first have to regard as foolish Pythagoras and all his followers, Plato’s teacher Philolaus and Plato himself, as Aristotle testifies in his book On the Heavens, Heraclides of Pontus and Ecphantus, Aristarchus of Samos, Nicetas, and Seleucus the mathematician.* Seneca himself, indeed, far from deriding it, mocks those who dismiss it as ridiculous; as he writes in his book On Comets:*
It will also help to clarify this if we know whether the universe revolves around the stationary Earth, or the universe is stationary and the Earth revolves. There have been those who have said that it is we who, without realizing it, are carried along by the natural world, and that it is not the motion of the heavens that causes them to rise and set, but that we ourselves rise and set. It is a matter worthy of consideration to know what our true state is: whether we stand still or move very fast, and whether God rotates all things round us or has us rotate.
Among the moderns, Nicolaus Copernicus was the first to revive the idea and confirm it amply in the whole of his book, and others have followed, among them William Gilbert, a distinguished doctor and philosopher, who discusses it at length and confirms it in the last book of his work On the Magnet;* Johannes Kepler,* an eminent living philosopher and mathematician in the service of the past and present emperor,* is of the same opinion; David Origanus, at the beginning of his Ephemerides,* devotes a long discussion to proving the motion of the Earth; and there is no lack of other authors who have published their reasons for supporting it. What is more, I could name numerous others living in Rome, Florence, Venice, Padua, Naples, Pisa, Parma, and other places, who uphold this position even though they have not published their views in print. So it is not a ridiculous position, but one which is held by very distinguished men; and if they are few in comparison with those who adhere to the commonly held view, this is evidence that it is hard to understand, not that it is unfounded.
Moreover, the weighty and convincing arguments which support this view can be deduced from the fact that all those who now follow it started off by believing the opposite—indeed for a long time laughed at it and considered it ridiculous, as Copernicus himself and I, and all its other living supporters can testify. Is it credible that an opinion which was generally considered to be unfounded, even foolish, and which was not upheld by more than one philosopher in a thousand, indeed was rejected by the prince of present-day philosophy,* could be established by any but the most solid proofs, the clearest experiments, and the most accurate observations? Surely no one will be persuaded to change their mind about an opinion which they have taken in with their mother’s milk and their earliest lessons, which almost the whole world considers obvious and which is supported by the authority of the most reputable authors, if the arguments against it are not wholly compelling. If we consider carefully we shall see that the support of one person who upholds the Copernican opinion is worth a hundred of those who oppose it, because those who are persuaded of the truth of the Copernican system all began by believing the opposite. So I reason as follows: those who have to be persuaded are either capable of understanding the reasoning of Copernicus and his followers, or not; this reasoning is either true and demonstrable, or false. If those who have to be persuaded are incapable of following the arguments, they will not be convinced by them whether they are true or false, and those who are capable of following the arguments will equally be unpersuaded if these arguments are false. Therefore neither those who understand nor those who do not will be persuaded by false arguments. So, since no one is going to be persuaded to change their mind by arguments which are false, it necessarily follows that if anyone is convinced of the opposite of what they believed to start with, the reasons which convince them must be true and convincing. And since there are indeed many who are persuaded by the arguments of Copernicus and others, these arguments must be effective and should not be dismissed as ridiculous, but deserve to be considered with the greatest care and attention.
As for judging the plausibility of an opinion by the sheer number of those who follow it, this can easily be shown to be unsound. There is no one who supports the Copernican view who did not originally believe the opposite; whereas, in contrast, there is not a single person who having adopted this view changed their mind again because of any arguments they may have heard. So it seems very likely, even to someone who has not heard the arguments on either side, that the proofs for the motion of the Earth are much stronger than those for the opposite view. If the probability of the two positions were put to a vote, I would gladly concede the point if the opposite view had one vote in a hundred more than mine—indeed, I would go further and would be willing for every single vote of my opponent to be worth ten of mine—provided the vote was conducted among those who had listened to all the arguments fully, had gone into them in detail, and had carefully examined all the reasoning and the evidence on both sides; for it is reasonable that only such people should be eligible to vote. So this is not an opinion which can be dismissed as ridiculous; rather, it is those who seek to place great weight on the universal view of the multitude who have not carefully studied these authors who are on shaky ground. How much less, therefore, should we pay attention to the noisy protests and idle chatter of those who have not even considered the first and most basic principles of these matters, and may not even be capable of understanding them in any case?
There are some who persist in saying that Copernicus only put forward the motion of the Earth and the fixity of the Sun as an astronomical hypothesis, as a more satisfactory way of saving the appearances of the heavens and calculating the motions of the planets, but did not believe this to be actually true in nature. They show—and I mean no disrespect in saying this—that they have been too ready to believe those whose views are perhaps based simply on their own opinion rather on a proper reading of Copernicus’ book or an understanding of the nature of the discussion, and so what they say is somewhat wide of the mark.
Turning first, then (and still confining ourselves to general conjectures), to the preface in which he dedicates his book to Pope Paul III, it is clear that, as if to comply with what was expected of him as an astronomer, Copernicus initially carried out his computations following the established philosophy and conforming to the Ptolemaic system, so that nothing was lacking. But then, setting aside the role of a pure astronomer and assuming that of an observer of nature, he undertook to examine whether this supposition which had already been introduced by astronomers, and which fully satisfied the requirements of calculating and accounting for the motions of each individual planet, could really exist in the natural world. He found that it was quite impossible for all the parts to be arranged in such a way, even though each part by itself was well proportioned, but that when they were all put together they formed a monstrous chimera. So, as I have said, he set about considering what could be the real natural structure of the universe, no longer from the point of view of the pure astronomer—whose calculations he had already fully satisfied—but in order to understand this profound problem of nature; for he was confident that, if it was possible to satisfy the mere appearances with hypotheses which were not true, this could be done much better by means of the true physical structure of the world. And so, drawing on a rich collection of genuine and direct observations about the courses of the stars (without which no such understanding is possible), he applied himself tirelessly to discovering this structure. First, prompted by the authority of so many great men of the past, he began to consider whether the Earth might be mobile and the Sun at rest—a possibility which would not have occurred to him if it had not been for the prompting of these authoritative figures, or if it had, he would have considered it (as he confessed he did when it first appeared to him) as a wild idea and a great paradox. But then, through painstaking observations, considerations which all agreed with each other, and conclusive proofs, he found it to be so in keeping with the harmony of the universe that he became completely convinced of its truth. He arrived at this position, therefore, not to satisfy the needs of the pure astronomer, but to satisfy the requirements of nature.
What is more, Copernicus goes on to say in the same place that he realized that publishing this opinion abroad would give him the reputation of a madman among the infinite numbers of followers of the current philosophy, not to mention the general masses; but he published it nonetheless, compelled by the insistence of the Cardinal of Capua and the Bishop of Kulm.* How much more mad would he have been if he had published this opinion believing that it was false, but presenting it as if he believed it to be true, in the certainty that he would be regarded as foolish by the whole world? Would he not rather have said that he was only putting it forward as an astronomer while denying it as a philosopher, thereby avoiding being universally called a fool, and winning praise for his sound judgement?
Besides, Copernicus states in detail the grounds and reasons for the ancients’ belief that the Earth was at rest, and then examines the force of each one in turn, showing them to be invalid.* What author with any sense would set out to refute the proofs in favour of a proposition which he deemed to be true? And what would have been the point of disproving and condemning a conclusion which he really wanted the reader to think he believed to be true? Such inconsistencies cannot be attributed to such a man.
We must recognize that the question of whether the Earth or the Sun moves or is at rest is a choice between contradictory positions, one of which must be true; we cannot fall back on saying that perhaps neither of them is correct. If, then, the fact is that the Earth is at rest and the Sun moves, and that the contrary position is absurd, what reasonable person could say that the false position accords better with the visible and observed appearances, and with the motions and positions of the stars, than the true one? Everyone knows that all the truths of nature harmonize with each other, and that false positions clash discordantly with the facts. Can it be, then, that the motion of the Earth and the fixity of the Sun agree in every respect with the position of all the other bodies in the universe, and with the very many observations that we and our predecessors have painstakingly made, and yet this position is false? And can the fixity of the Earth and the motion of the Sun be considered true, and yet not be in agreement with the other truths? If it were possible to say that neither position is true, then it might be the case that one preserves the appearances better than the other; but to say of two positions, one of which is necessarily false and the other true, that the false one better accords with the effects in nature, is beyond my comprehension. Rather, I ask: if Copernicus admits that he has fully satisfied the astronomers working with the hypothesis which is commonly held to be true, how can anyone say that he wanted or was able to satisfy them again with another hypothesis which is foolish and false?
I move on now to examine in detail the nature of the question, and to show how much careful attention is necessary in discussing it.
There are two kinds of supposition which have so far been made by astronomers. Some are primary, and concern the absolute truths of nature; others are secondary, and have been imagined to explain the appearances of the stellar motions, as these seem in some way not to agree with the primary, true suppositions. Ptolemy, for example, before attempting to account for the appearances, makes certain suppositions not as a professional astronomer, but as a thoroughgoing philosopher—borrowing them, indeed, from the philosophers themselves. He supposes that the celestial motions are all circular and regular, that is, uniform; that the heavens are spherical in shape; that the Earth is at the centre of the celestial sphere, and that it too is spherical, and at rest; and so on. Turning then to the irregularities which we perceive in the motions and the distances of the planets, which appear to clash with the established primary physical suppositions, he goes on to make another kind of supposition, with the aim of explaining, without altering the primary suppositions, why there is such evident and observable irregularity in the motions of the stars as they approach or recede from the Earth. In order to do this he introduces other circular motions which do not have the Earth as their centre, but describe eccentric circles and epicycles. It is this second kind of supposition which the astronomer can be said to posit to meet the needs of his computations, without having to maintain that they are actually true in nature.
Let us now consider which kind of hypothesis Copernicus considered the motion of the Earth and the fixity of the Sun to be. There is no doubt that he placed it among the primary and necessary suppositions about nature; for as I have said, he had already given the astronomers satisfaction by the other route, and he only applied himself to this new one to resolve the greatest problem of nature. In fact, so far was he from adopting this supposition in order to satisfy astronomical calculations that he himself, when he comes to these calculations, sets aside the new position and returns to the old, as being more accessible and easier to learn, and still wholly suitable for these computations. For although both suppositions, namely whether the Earth revolves or the heavens revolve, are inherently equally suitable for particular calculations, nonetheless many geometricians and astronomers had in many books already demonstrated the properties of right and oblique ascension of parts of the zodiac in relation to the equinoctial, the declinations of the ecliptic,* the variety of the angles between it and the oblique horizons and the meridian, and a hundred and one other specific details which are needed for the completeness of astronomical science. So Copernicus himself, when he considers these details of the primary motions, discusses them in the old manner, as made of circles drawn in the heaven around the unmoving Earth, even though in reality the fixity and motionlessness were in the highest heaven, called the Primum Mobile, and the motion was in the Earth. This is why he concludes, at the end of the preface to the second book: ‘Let no one be surprised if I still speak of the rising and setting of the Sun and the stars, and similar things. It should be recognised that I am using accustomed figures of speech which everyone can understand; nonetheless I am always conscious that “To us who are being carried along on the Earth, the Sun and Moon pass over us, and the stars return to their former places and move away”.’*
There is no doubt, then, that Copernicus posits the mobility of the Earth and the fixity of the Sun solely in order to establish this hypothesis of the first kind; and that in contrast, when he comes to dealing with astronomical computations he reverts to positing the old hypothesis, in which the circles of the basic motions are imagined as occurring in the highest heaven and moving around the stationary Earth, since ingrained habit makes this easier for everyone to grasp. But why should I labour this point? Such is the strength of the truth and the weakness of falsehood that those who argue in this way reveal their own imperfect grasp of these matters, allowing themselves to be persuaded that Ptolemy and the other authoritative astronomers did not believe the second kind of hypothesis to be true in nature, but considered them mere chimerical fantasies introduced for the sake of their astronomical computations. Their only basis for this deluded opinion is a passage where Ptolemy, having been unable to observe more than one simple anomaly in the Sun, writes that this could be explained by positing either a simple eccentric or an epicycle on a concentric, and adds that he will adopt the first hypothesis as being simpler than the second.* On the slender basis of these words some argue that Ptolemy considered both suppositions to be unnecessary, indeed that they were totally fictitious, since he said that either would serve although only one could be a correct explanation of what we observe in the Sun. What a shallow argument! Surely anyone can see that, if the primary suppositions are taken to be true, namely that the motions of the planets are circular and regular, and if, as the evidence of our senses undeniably shows, the planets all move through the zodiac at different speeds, indeed the majority of them sometimes stand still or move in a retrograde direction, and that they appear sometimes very large and close to the Earth and at other times very small and far away—surely, I say, anyone trained in the discipline who understands these basic observations realizes that eccentrics and epicycles must actually exist in nature. A misunderstanding, which is excusable in those who are not trained in these sciences, reveals in those who profess them that they do not even understand the meaning of the terms eccentric and epicycle: it is as if someone could identify the letters G, O, and D but then denied that when they are combined they form the word GOD, and claimed that they spelt the word SHADOW. But if discursive reasoning is not enough to persuade them that eccentrics and epicycles must necessarily have a real existence in nature, then the evidence of their own senses ought to convince them. The four Medicean planets,* which are very far from circling the Earth, can be seen to describe four small circles around Jupiter, that is, four epicycles; the appearance of Venus, which is sometimes full of light and sometimes has very thin horns, necessarily shows that it revolves around the Sun and not around the Earth, that is, that its course is an epicycle; the same can be deduced of Mercury. And the fact that the three superior planets* are very close to the Earth when they are in opposition to the Sun, and very remote from the Earth at the time of their conjunction, so that Mars appears more than fifty times bigger when it is at its nearest point than when it is furthest away (with the result that it has sometimes been feared that it had got lost and disappeared, when in fact it was simply invisible because it was so distant), can only lead to the conclusion that their revolution is made in eccentric circles, or in epicycles, or in a combination of the two, if we take account of the second anomaly.* So to deny that there are eccentrics and epicycles in the motions of the planets is like denying light to the Sun; it is a self-contradiction.
Let me apply this specifically to the point at issue here. Some argue that modern astronomers introduce the motion of the Earth and the fixity of the Sun purely hypothetically, in order to save the appearances and to facilitate their calculations, in the same way as they accept eccentrics and epicycles for the same reason even though they regard these as illusions which cannot occur in nature. My reply to them is that I will gladly accept their argument provided they accept the same condition, namely that the mobility of the Earth and the fixity of the Sun are true or false in nature in the same way as epicycles and eccentrics are. So let them do all in their power to disprove the real actual existence of these circles, and if they succeed in demonstrating that they do not exist in nature I shall immediately admit defeat, and acknowledge that the mobility of the Earth is a great absurdity. But if they find that they have to accept epicycles and eccentrics, then let them also admit to the mobility of the Earth, and acknowledge that they have been convicted by their own contradictions.
I could make many other points on this question, but since I doubt whether anyone who is not convinced by what I have said already is likely to change their mind because of any number of other arguments, let these suffice. I will simply add what might be the reason which has enabled some to maintain, with at least an appearance of plausibility, that Copernicus himself did not really believe in the truth of his own hypothesis.
On the back of the title-page of Copernicus’ book is a preface to the reader, which is not by the author, as it speaks of him in the third person, and is unsigned.* This clearly states that the reader should not believe for a moment that Copernicus considered his position to be true, but that it was simply a fiction which he introduced for the purpose of calculating the motions of the heavens; and it ends by saying that it would be folly to believe that the theory is actually true. This conclusion is stated so firmly that anyone who reads no further, and who assumes that it was at least added with the author’s consent, can be excused for their error. But I let everyone judge for themselves how much weight should be given to the view of someone who would condemn a book without reading anything more than a brief preface by the printer or bookseller. It can only be a preface added by the bookseller to make the book sell, for the general public would have considered it sheer fantasy if it had not had some such qualification added to it, and the customer usually glances at such prefaces before buying the book. And that the preface was not only not written by the author, but was added without his consent, is clear from the sheer errors of terminology which it contains, which the author would never have accepted.
The author of this preface writes that only someone wholly ignorant of geometry and optics could think it probable that Venus has such a large epicycle that it can sometimes precede and sometimes follow the Sun by 40 degrees or more, as this would mean that when it is at its highest point its diameter would appear to be only a quarter of what it appears to be at its lowest point, and its volume at its lowest point would appear to be sixteen times greater than at its highest. He says that this is contrary to the observations made throughout the centuries, but in saying this he shows, first, that he does not know that Venus precedes and follows the Sun by just under 48 degrees, not 40 as he says. What is more, he says that its diameter would appear four times, and its volume sixteen times greater at its lowest point than at its highest. This shows, first of all, his ignorance of geometry, since a globe whose diameter was four times larger than another would have a volume sixty-four times greater, not sixteen times as he says. Hence, if he considered such an epicycle to be absurd and wanted to show that it was impossible in nature then, if he had understood geometry, he could have made the absurdity all the greater, since the position which he rejects and which is postulated by astronomers has Venus diverging from the Sun by nearly 48 degrees, and its distance at its furthest from the Earth must be more than six times greater than when it is at its nearest. So its diameter would appear to be more than six times greater, and its volume more than 216 times greater, not just sixteen times as he says.* These are such gross errors that it is unbelievable that they should have been committed by Copernicus, or by anyone who was not completely inexperienced. But in any case, why cite the vastness of an epicycle as so great an absurdity that Copernicus could not have believed his conclusions were true, and that neither should others believe them to be true? He should have remembered that in chapter 10 of book I Copernicus, to refute other astronomers who allege that it is absurd to give Venus such an epicycle, which exceeds the whole lunar orbit by more than 200 times and yet contains nothing inside it, eliminates this absurdity by showing plainly that the orbit of Venus contains both the orbit of Mercury and the body of the Sun itself, which is at its centre. What a shallow argument this is, then, to try to show that a theory is erroneous and false on the basis of a difficulty which the theory in question not only does not introduce into nature, but which it entirely removes—just as it removes all the other enormous epicycles which other astronomers were obliged to posit under the other system! This is as much as I shall say about the author of the preface to Copernicus’ book, for it is fair to infer that if he had tried to put forward any other arguments based on the science of astronomy, he would simply have multiplied his errors.
Finally, to remove any shadow of doubt, if the fact that such great differences in the apparent size of Venus are not perceptible to our sight should call into question its revolution around the Sun, in conformity with the Copernican system, then let us make diligent observation with an appropriate instrument, namely a perfect telescope, which will show that these are indeed confirmed by observation and experience. For Venus will be seen when it is nearest to the Earth to be horned, and to be at least six times greater in diameter than when it is at its furthest distance, namely above the Sun, at which point it appears round and very small. And if the fact that these variations are not visible to the naked eye, for the reasons that I have explained elsewhere, should seem to give grounds for denying the Copernican position, so now that we can see that it corresponds in this and every other detail exactly to what is observed, let all doubts be set aside and let it be recognized as true and correct.* And if anyone wishes to have confirmation of the opinion of Copernicus himself on every other part of this marvellous system, let them read the author’s work in its entirety, not a vain piece of writing added by the printer; and they will be left in no doubt that Copernicus was firmly convinced that the Sun is at rest and that the Earth moves.
* * *
The mobility of the Earth and the fixity of the Sun, if they are shown to be true in nature by philosophers, astronomers, and mathematicians drawing on the experience of the senses, detailed observations, and necessary demonstrations, can never be contrary to the faith or to the Holy Scriptures; rather, if in this case there are passages of Scripture which appear to state the contrary, we should say that this is because of the weakness of our intellect, and that we have been unable to penetrate the true meaning of Scripture in this matter. This is a clear and well-established principle, since two truths cannot contradict each other. So if anyone wishes legally to condemn such a view they must first show it to be false in nature, by rebutting the arguments which support it.
The question then arises, from which end one should start in order to establish that it is false: by citing the authority of Scripture, or by refuting the experiments and proofs of the astronomers and philosophers. My reply is that one should start from the place that is most secure and least likely to give rise to scandal, that is, from the scientific and mathematical arguments. For if the arguments proving the mobility of the Earth are found to be fallacious and the contrary arguments sound, then we shall have established that this view is false and the contrary proposition, which we now see as being in keeping with the meaning of Scripture, is true; in which case the false view can freely and safely be condemned. If on the other hand the arguments supporting the mobility of the Earth are found to be true and compelling, the authority of Scripture is not thereby undermined, but we shall be more cautious, recognizing that in our ignorance we were not able to penetrate its true meaning. This we shall then go on to find, with the help of the new scientific truth we have discovered. Hence we are always on firm ground by starting with the arguments. But if we condemned such a proposition without having examined the arguments, basing ourselves solely on what we took to be the clear meaning of Scripture, how great would be the scandal if the experience of the senses and good reasons then showed that we were wrong? Who, in that case, would have brought confusion on the Church—those who put forward a considered opinion based on proof, or those who dismissed it out of hand? So it is clear which is the safer route to take.
Moreover, once it is granted that a scientific proposition whose truth is demonstrated by physical and mathematical proofs can never contradict Scripture, but that in such a case it is the weakness of our intellect which has failed to penetrate Scripture’s true meaning, anyone who then cited the authority of the same passages of Scripture in order to refute such a proposition would fall into the error called ‘begging the question’. For if scientific proofs have cast doubt on the true meaning of Scripture, we cannot then take the meaning of Scripture as a secure basis for refuting the same proposition. Rather, we have to challenge the proofs and expose their fallacies by means of other arguments, experiments, and more accurate observations. Once we have established the true position as it is in nature, then and only then can we be certain of the true meaning of Scripture and use it with confidence. Thus, the secure way of proceeding is to start from the proofs, confirming those which are true and refuting those which are false.
If the Earth really does move, we cannot change nature so that it does not move; but we can easily resolve the inconsistency with Scripture, simply by admitting that we cannot penetrate its true meaning. So the secure way of avoiding error is to begin with natural and astronomical enquiries, not with references to Scripture.
It will be objected that the Church Fathers all agree in interpreting the passages of Scripture relating to this point according to the straightforward plain meaning of the words, and that therefore we should not read them in a different way or challenge the accepted interpretation, as this would be to accuse the Fathers of heedlessness or negligence. I agree that such respect for the Fathers is only right and proper, but I would add that there is a perfectly sound reason for their attitude: they never expounded the Scriptures in any but the literal sense in these matters, because at that time the idea that the Earth moves was completely forgotten, and nobody even spoke about it, let alone wrote it or upheld it; so the Fathers cannot be accused of negligence if they did not reflect on something which was totally hidden from them. That they did not reflect on it is clear from the fact that there is not a word about such an opinion in any of their writings; indeed, to say that they did consider it would make it all the more dangerous to condemn it now, as this would mean that the Fathers had considered it and, far from condemning it, had cast no doubt on it whatever.
The Church Fathers, then, have a clear and ready defence. But it would be much harder, if not impossible, to excuse from a similar charge of negligence the supreme Pontiffs, Councils, and compilers of the Index, if for eighty years they had allowed an opinion and a book to circulate with the approval of the Church—a book written at the command of a Pope, then printed by order of a Cardinal and a Bishop, and dedicated to another Pope, and one moreover which is quite specific in its teaching, so that it cannot be said to have remained hidden—if its teaching was erroneous and to be condemned. So if we are, quite rightly, to avoid the disrespect of accusing our ancestors of negligence, we should also be careful lest in our anxiety to avoid one absurdity we fall into a worse one.
If, however, anyone should think it disrespectful to abandon the common interpretation of the Fathers, even of propositions concerning the natural world which they did not discuss or the contrary of which they never considered, my question is this: what are we to do if necessary proof should show that the actual fact in nature is the contrary of what they upheld? Which of the two principles should we compromise—the principle which states that no proposition can be both true and false, or the one which requires us to hold as articles of faith natural propositions endorsed by the common interpretation of the Fathers? Unless I am mistaken, it seems much safer to compromise on this second principle than to try to impose as an article of faith a natural proposition which conclusive proofs have shown to be false in fact and in nature. It seems to me that the common interpretation of the Fathers should be absolutely authoritative in propositions which they discussed and for which there were no proofs to the contrary, and no possibility of such proofs ever being found. It seems quite clear that the Council* requires agreement with the common interpretation of the Fathers only in matters of faith and morals; but I will not pursue this.
1. Copernicus posits eccentrics and epicycles; it was not these, which undoubtedly exist in the heavens, but other disproportionate assumptions which prompted him to reject the Ptolemaic system.
2. Philosophers, if they are true philosophers, that is, lovers of the truth, should not be resentful but grateful if someone shows them the truth and they realize that they have been mistaken; and if their opinion withstands a challenge, they should see that as a source of pride and not a cause for indignation. Theologians should not be resentful if this opinion is shown to be false, because then they will be free to condemn it; if it is shown to be true, they should rejoice that someone has shown them the way to discover the true meaning of Scripture and spared them the disgrace of condemning a proposition which is true.
As for showing the Scriptures to be false, that is not and never has been the intention of Catholic astronomers such as myself. On the contrary, our view is that the Scriptures agree perfectly with demonstrated natural truths. Some theologians who are not astronomers should beware of making the Scriptures appear false by trying to interpret them as contrary to propositions which could be true and proven in nature.
3. We may well encounter some difficulties in expounding the Scriptures, etc.; but this is because of our ignorance, not because there really is, or might be, any insuperable difficulty in showing that they agree with demonstrated truths.
4. The Council speaks of ‘matters of faith and morals’. In reply to the claim that a given proposition is a matter of faith ‘with respect to the one who speaks it’ even if not ‘by reason of the object’ and that therefore it comes within the terms of the Council’s ruling, it should be pointed out that everything in Scripture is a matter of faith ‘with respect to the one who speaks it’ and therefore should be included in the ruling, which is clearly not the case; if it had been, it would have said ‘in every word of Scripture the exposition of the Fathers is to be followed’, and not just ‘in matters of faith and morals’. Hence it is clear that the intended meaning was ‘in matters of faith by reason of the object’. This is why it is much more a matter of faith to believe that Abraham had sons, or that Tubal had a dog, because Scripture says they did,* than to believe that the Earth moves, although this too can be read in Scripture, and it is a heresy to deny the former but not the latter. For there have always been men who had two, four, or six sons, or for that matter none; and there have always been some men who had dogs, and others not; so it is equally credible that one man had sons or dogs and another did not, and there is no reason why the Holy Spirit should affirm anything other than the truth on such matters, since negative and positive statements are both equally credible to everyone. But this is not the case with the mobility of the Earth and the fixity of the Sun, which are ideas far beyond the comprehension of the masses; and it pleased the Holy Spirit to accommodate the pronouncements of Scripture to the understanding of the masses in these matters which do not pertain to their salvation, even though the true facts are otherwise.
5. As regards saying that the Sun is in the heavens and the Earth is not, as Scripture appears to affirm, this seems to me to be simply a matter of our perception and of speaking in terms which we can understand. The reality is that everything which is surrounded by the heavens is ‘in’ the heavens, just as everything that is surrounded by a city’s walls is in the city; indeed it could be said that nowhere is more ‘in’ the heavens or ‘in’ the city than the middle or, as we say, in the heart of the city or the heavens. The difference as far as our understanding is concerned is that we regard the elemental region which surrounds the Earth as being quite distinct from the heavens themselves. This would be true wherever we placed the elemental region, and it will always be the case that we will think of the heaven as being above and the Earth beneath, because all the inhabitants of the Earth have the heaven above their heads—what we refer to as ‘up’—and the centre of the Earth beneath their feet—what we call ‘down’. So from our point of view the centre of the Earth and the surface of the heaven are the furthest points there are, the extremes of the diametrically opposed points which we call ‘up’ and ‘down’.
6. It is absolutely prudent not to believe that there is proof of the mobility of the Earth until it is demonstrated, and we do not ask that anyone should believe such a thing without proof. Indeed we ask only that, for the benefit of the Church, anything which the upholders of this position can produce should be examined with the greatest rigour, and that nothing should be conceded to them unless the arguments they rely on far outweigh those on the other side; if their arguments are only 90 per cent correct, they should be rejected. But if the arguments produced by the philosophers and astronomers who oppose them are shown to be mostly false and all immaterial, then the other side should not be dismissed as a mere paradox which can never be demonstrably proved. There is no risk in offering such generous terms, for those who uphold the false position can never have any valid argument or evidence on their side, whereas on the side of the truth everything will necessarily come together and agree.
7. It is true that showing that the mobility of the Earth and the fixity of the Sun save the appearances is not the same as proving that these hypotheses are actually true in nature; but it is equally true—indeed more so—that the other commonly accepted system cannot satisfactorily explain these appearances. There is no doubt that the accepted system is false, and it is clear that the new one, which fits the appearances very well, may be true. And no greater truth can or should be expected from a theory than that it should meet all the relevant appearances.
8. It is not suggested that in cases of doubt we should abandon the teaching of the Fathers, but only that where there is doubt we should try to arrive at certainty, and that therefore we should not dismiss out of hand the lines of reasoning which great philosophers and astronomers follow and have followed. Then, having exercised due diligence, we should reach our decision.
9. We believe that Solomon, Moses, and all the other Scriptural authors understood the structure of the universe perfectly well, just as they knew that God does not have hands or feet, and that He does not experience anger, forgetfulness, or repentance; and we have no intention of questioning this. But we follow what the Church Fathers and in particular St Augustine have said on this matter, that the Holy Spirit chose to dictate to them in this way for the reasons we have given, etc.
10. The illusion that the shore appears to move and the ship to stand still is familiar to us because we have often stood on the shore watching the motion of boats, and been on a boat watching the shore; so if we were able to stand now on the Earth and now on the Sun or another star, we might be able to tell from sense impressions which of them was moving. But even then, if we only looked at these two bodies we would always think that the one on which we were standing was motionless, in the same way as someone who only looks at the boat and the water will always think that the water is flowing past and the boat is stationary. Besides, the great disparity between a small boat, isolated from all its surroundings, and a great expanse of shore which all our experience tells us is immobile in relation to both the water and the boat, is quite unlike the comparison between two bodies both of which are solid and equally disposed to motion or rest. It would be more proper to make a comparison of two ships with each other: in this case we would always think that the one we were standing on was stationary, as long as we were unable to compare the two ships with anything else.
There is, then, a great need to make allowance for illusory appearances when considering whether the Earth or the Sun is in motion, for it is clear that anyone standing on the Moon or any other planet would always have the impression that they were standing still and the other stars were in motion. Those who uphold the common opinion will have to give very clear answers to these and many other more evident arguments before they can claim to be taken seriously, let alone to win approval—just as we have responded in minute detail to all the arguments that have been raised against us. In any case, neither Copernicus nor his followers have ever used this analogy of the shore and the ship to prove that the Earth is in motion and the Sun is at rest; they have simply used it as an example, not to prove the truth of their position, but to show that there would be no contradiction between our sense impressions telling us that the Earth is at rest and the Sun in motion, and the reality being the opposite. Indeed, if this was Copernicus’ proof, or if his other arguments were not more conclusive than this, then I am sure that no one would endorse what he says.