The Essential Galileo

by Galilei, Galileo, Finocchiaro, Maurice A.

  To this type belong, I think, those who will not or cannot understand the demonstrations and the observations with which the originator and the followers of this position confirm it, and who thus are concerned with putting forth Scripture. They do not notice that the more scriptural passages they produce, and the more they persist in claiming that these are very clear and not susceptible to other meanings besides what they advance, the greater the harm resulting to the dignity of Scripture if later the truth were known to be clearly contrary and were to cause confusion (especially if these people’s judgment had much authority in the first place). There would be harm and confusion at least among those who are separated from the Holy Church, toward whom she is nevertheless very zealous like a mother who wants to be able to hold them on her lap. Your Highness can therefore see how inappropriate is the procedure of those who, in disputes about nature, as a first step advance arguments based on scriptural passages, especially when very often they do not adequately understand these.

  However, if these people truly feel and fully believe they have the true meaning of some particular scriptural passage, it would have to follow necessarily that they are also sure of possessing the absolute truth about the physical conclusion they intend to discuss and, at the same time, that they know they have a very great advantage over the opponent, who has to defend the false side; for whoever is supporting the truth can have many sense experiences and many necessary demonstrations on his side, [342] whereas the opponent cannot use anything but deceptive presentations, paralogisms, and fallacies. Now, if they know that by staying within the limits of the physical subject of discussion and using only philosophical weapons, they are in any case so superior to the opponent, why is it that when they come to the debate they immediately seize an irresistible and fearful weapon, so that their opponent is frightened at its mere sight? To tell the truth, I believe they are the ones who are frightened and are trying to find a way of repelling the enemy because they are unable to resist his assaults. That is why they forbid him to use the reason which he received through the Divine Goodness and why they abuse the very proper authority of the Holy Scripture, which (when adequately understood and used) can never conflict with clear observation and necessary demonstrations, as all theologians agree. However, the fact that these people take refuge in Scripture, to cover up their inability to understand and to answer the contrary arguments, should be of no advantage to them, if I am not mistaken, since till now such an opinion has never been condemned by the Holy Church. Therefore, if they wanted to proceed with sincerity, they could remain silent and admit their inability to discuss similar subjects; or else they could first reflect that it is not within their power, nor within that of anyone but the Supreme Pontiff and the sacred Councils, to declare a proposition erroneous, but that they are free to discuss whether it is false; then, understanding that it is impossible for a proposition to be both true and heretical, they should focus on the issue which more concerns them, namely, on demonstrating its falsity; if they were to discover this falsity, then either it would no longer be necessary to prohibit it because no one would follow it, or its prohibition would be safe and without the risk of any scandal.

  Thus let these people apply themselves to refuting the arguments of Copernicus and of the others, and let them leave its condemnation as erroneous and heretical to the proper authorities; but let them not hope that the very cautious and very wise Fathers and the Infallible One with his absolute wisdom are about to make rash decisions like those into which they would be rushed by their special interests and feelings. [343] For in regard to these and other similar propositions which do not directly involve the faith, no one can doubt that the Supreme Pontiff always has the absolute power of permitting or condemning them; however, no creature has the power of making them be true or false, contrary to what they happen to be by nature and de facto. So it seems more advisable to first become sure about the necessary and immutable truth of the matter, over which no one has control, than to condemn one side when such certainty is lacking; this would imply a loss of freedom of decision and of choice insofar as it would give necessity to things which are presently indifferent, free, and dependent on the will of the supreme authority. In short, if it is inconceivable that a proposition should be declared heretical when one thinks that it may be true, it should be futile for someone to try to bring about the condemnation of the earth’s motion and sun’s rest unless he first shows it to be impossible and false.

  [§4.2.6] There remains one last thing for us to examine: to what extent it is true that the Joshua passage34 can be taken without altering the literal meaning of the words, and how it can be that, when the sun obeyed Joshua’s order to stop, from this it followed that the day was prolonged by a large amount.

  Given the heavenly motions in accordance with the Ptolemaic system, this is something which in no way can happen. For the sun’s motion along the ecliptic takes place in the order of the signs of the zodiac, which is from west to east; this is contrary to the motion of the Prime Mobile from east to west, which is what causes day and night; therefore, it is clear that if the sun stops its own true motion, the day becomes shorter and not longer and that, on the contrary, the way to prolong it would be to speed up the sun’s motion; thus, to make the sun stay for some time at the same place above the horizon, without going down toward the west, [344] it would be necessary to accelerate its motion so as to equal the motion of the Prime Mobile, which would be to accelerate it to about three hundred and sixty times its usual motion. Hence, if Joshua had wanted his words taken in their literal and most proper meaning, he would have told the sun to accelerate its motion by an amount such that, when carried along by the Prime Mobile, it would not be made to set; but his words were being heard by people who perhaps had no other knowledge of heavenly motions except for the greatest and most common one from east to west; thus he adapted himself to their knowledge and spoke in accordance with their understanding, because he did not want to teach them about the structure of the spheres but to make them understand the greatness of the miracle of the prolongation of the day.

  Perhaps it was this consideration that first led Dionysius the Areopagite (in the Letter to Polycarpus) to say that in this miracle the Prime Mobile stopped and, as a consequence of its stopping, all other celestial spheres stopped. The same opinion is held by St. Augustine himself (in book 2 of On the Miracles of the Holy Scripture), and the Bishop of Avila supports it at length (in questions 22 and 24 of his commentary on chapter 10 of Joshua). Indeed one sees that Joshua himself intended to stop the whole system of celestial spheres, from his giving the order also to the moon, even though it has nothing to do with the prolongation of the day; in the injunction given to the moon one must include the orbs of the other planets, which are not mentioned here, as they are not in the rest of the Holy Scripture, since its intention has never been to teach us the astronomical sciences.

  I think therefore, if I am not mistaken, that one can clearly see that, given the Ptolemaic system, it is necessary to interpret the words in a way different from their literal meaning. Guided by St. Augustine’s very useful prescriptions, I should say that the best nonliteral interpretation is not necessarily this, if anyone can find another which is perhaps better and more suitable. So now I want to examine whether the same miracle could be understood in a way more in accordance with what we read in Joshua, if to the Copernican system we add [345] another discovery which I recently made about the solar body. However, I continue to speak with the same reservations—to the effect that I am not so enamored with my own opinions as to want to place them ahead of those of others; nor do I believe it is impossible to put forth interpretations which are better and more in accordance with the Holy Writ.

  Let us first assume, in accordance with the opinion of the abovementioned authors, that in the Joshua miracle the whole system of heavenly motions was stopped, so that the stopping of only one would not introduce unnecessarily universal confusion and great turmoil in the whole ord
er of nature. Second, I think that although the solar body does not move from the same place, it turns on itself, completing an entire rotation in about one month, as I feel I have conclusively demonstrated in my Sunspot Letters; this motion is sensibly seen to be inclined southward in the upper part of the globe and thus to tilt northward in the lower part, precisely in the same manner as the revolutions of all planetary orbs. Third, the sun may be regarded as a noble body, and it is the source of light illuminating not only the moon and the earth but also all the other planets, which are in themselves equally dark; having conclusively demonstrated this, I do not think it would be far from correct philosophizing to say that, insofar as it is the greatest minister of nature and, in a way, the heart and soul of the world, it transmits to the surrounding bodies not only light, but also (by turning on itself) motion; thus, just as all motion of the limbs of an animal would cease if the motion of its heart were to cease, in the same way if the sun’s rotation stopped then all planetary revolutions would also stop. Now, concerning the admirable power and strength of the sun I could quote the supporting statements of many serious writers, but I want to restrict myself to just one passage from the book The Divine Names by the Blessed Dionysius the Areopagite. He writes this about the sun: “Light also gathers and attracts to itself all things that are seen, that move, that are illuminated, that are heated, and, in a word, that are surrounded by its splendor. Thus the sun is called Helios because [346] it collects and gathers all things that are dispersed.” And a little below that he again writes about the sun: “If in fact this sun, which we see and which (despite the multitude and dissimilarity of the essences and qualities of observed things) is nevertheless one, spreads its light equally and renews, nourishes, preserves, perfects, divides, joins, warms up, fertilizes, increases, changes, strengthens, produces, moves, and vitalizes all things; and if everything in this universe in accordance with its own power partakes of one and the same sun and contains within itself an equal anticipation of the causes of the many things which are shared; then certainly all the more reason, etc.” Therefore, given that the sun is both the source of light and the origin of motion, and given that God wanted the whole world system to remain motionless for several hours as a result of Joshua’s order, it was sufficient to stop the sun, and then its immobility stopped all the other turnings, so that the earth as well as the moon and the sun (and all the other planets) remained in the same arrangement; and during that whole time the night did not approach, and the day miraculously got longer. In this manner, by stopping the sun, and without changing or upsetting at all the way the other stars appear or their mutual arrangement, the day on the earth could have been lengthened in perfect accord with the literal meaning of the sacred text.

  Furthermore, what deserves special appreciation, if I am not mistaken, is that with the Copernican system one can very clearly and very easily give a literal meaning to another detail which one reads about the same miracle; that is, that the sun stopped in the middle of heaven. Serious theologians have raised a difficulty about this passage: it seems very probable that, when Joshua asked for the prolongation of the day, the sun was close to setting and not at the meridian; for it was then about the time of the summer solstice, and consequently the days were very long, so that if the sun had been at the meridian then it does not seem likely that it would have been necessary to pray for a lengthening of the day in order to win a battle, since the still remaining time of seven hours or more could very well have been sufficient. Motivated by this argument, very serious theologians have held that the sun really was close to setting; [347] this is also what the words “Sun, stand thou still” seem to say, because if it had been at the meridian, then either there would have been no need to seek a miracle or it would have been sufficient to pray merely for some slowing down. This opinion is held by the Bishop of Gaeta,35 and it is also accepted by Magalhaens,36 who confirms it by saying that on the same day, before the order to the sun, Joshua had done so many other things that it was impossible to complete them in half a day; thus they really resort to interpreting the words “in the midst of heaven” somewhat implausibly, saying they mean the same as that the sun stopped while it was in our hemisphere, namely, above the horizon. We can remove this and every other implausibility, if I am not mistaken, by placing the sun, as the Copernican system does and as it is most necessary to do, in the middle, namely, at the center of the heavenly orbs and of the planetary revolutions; for at any hour of the day, whether at noon or in the afternoon, the day would have been lengthened and all heavenly turnings stopped by the sun stopping in the middle of the heavens, namely, at the center of the heavens, where it is located. Furthermore, this interpretation agrees all the more with the literal meaning inasmuch as, if one wanted to claim that the sun’s stopping occurred at the noon hour, then the proper expression to use would have been to say that it “stood still at the meridian point,” or “at the meridian circle,” and not “in the midst of heaven”; in fact, for a spherical body such as heaven, the middle is really and only the center.

  As for other scriptural passages which seem to contradict this position, I have no doubt that, if it were known to be true and demonstrated, those same theologians who consider such passages incapable of being interpreted consistently with it (as long as they regard it as false) would find highly congenial interpretations for them; this would be especially true if they were to add some knowledge of the astronomical sciences to their expertise about Holy Writ. Just as now, when they consider it false, they think that whenever they read Scripture they only find statements repugnant to it, so if they thought otherwise they would perchance find an equal number of passages agreeing with it. Then perhaps they would judge [348] it very appropriate for the Holy Church to tell us that God placed the sun at the center of heaven and that therefore He brings about the ordered motions of the moon and the other wandering stars by making it turn around itself like a wheel, given that she sings:

  Most holy Lord and God of heaven,