[Margin: The restriction and state of the question.]
[I.] I do not raise the question about the motion of the Prime Mobile, for all confess that it is most equable and uniform, as the most universal rule of all the motions which take place in this sensible world; and concerning this hold those words of the Philosopher (2 On the Heavens, ch. 6, text 35): “But about the motion of the heaven—that it is regular and not irregular—it must next be reviewed.” But I say this of the first heaven and of the first lation. And speaking of this very [thing] (8 Physics, text 76), he says: “For indeed, since the measure of motions is circular revolution, this must be first—for all things are measured by [what is] first; and because it is first, it is the measure of the others; and moreover it happens to be regular.” Nor do I raise a doubt about the proper motion of the Fixed [stars] in longitude, for I already suppose it to be equal, from what was said in bk. 3, ch. 28 and 30, and bk. 6, ch. 17. There remains, therefore, the controversy about the motion of the Planets, composed of several mixed kinds—namely, according to longitude, latitude, and depth or altitude. But neither about this is there a doubt that it appears to us unequal, and that, with respect to the center [or] surface of the earth, it traverses unequal parts of the heaven in equal times; for this I now think is established by the most manifest experiments of the observations, and persuaded to the reader from what was said—about the Sun in bk. 3, from ch. 13; about the Moon in bk. 4, from ch. 18; and about the rest of the Planets in bk. 7, sect. 1, ch. 7, and sect. 2 and 3.
We ask, therefore, about the motion of the Planets—per se, and from the nature of the movable Planets, or rather from the intention of God the Creator and first institutor of such motions, and so from the intention of the Intelligence moving the Planet (and obeying the divine intention in every way): namely, whether it is unequal as it appears; or whether, to us indeed (placed per accidens outside the place from which it ought to be regarded) it seems unequal, but per se, and regarded from the place whence it ought to be regarded, is equal and uniform—just as if a Ruler [straightedge] be straight in itself, but on account of refraction in water appear curved, like an oar; or [as] a man be really shaggy and of a longish beard, but, regarded from afar, appear smooth and beardless, the hairs not standing out, or not appearing, from too great a distance.
[Margin: 1st opinion, for the equality of the celestial motions.]
The first Opinion was that the motions of all the stars are equal in their circles.
[Margin: Anaximenes. — Aristotle.]
For Anaximenes said that the stars are turned in the same way, both above and around the earth (as Plutarch relates, bk. 2 On the Opinions of the Philosophers, ch. 16); and Aristotle (8 Physics, text 76; and 2 On the Heavens, from text 35) adduces such reasons for the regularity of the first motion of the supreme heaven that they hold equally for every circular motion which takes place in the heaven. For he says it is regular for this reason: because, being circular, it has no beginning or end, by approaching which it must be carried more swiftly.
[Margin: 1st reason of Aristotle.]
For he says, in that text 76: “Moreover, it happens that only the circular [motion] is regular; for those [motions] which are made along straight [lines] are carried irregularly from the beginning and to the end—for all [bodies], the more they are distant from that which is at rest, are carried the more swiftly. But of the circular alone, neither beginning nor end is in it by nature, but outside”—where he speaks of the merely natural motions of simple bodies. But (2 On the Heavens, text 35), speaking more universally, he says: “For if it were moved irregularly, it is manifest that there would be in it intension, and a standing-still, and remission of the lation; for every irregular lation has both intension and a standing-still. But the standing-still is either in the terminus a quo, or in the terminus ad quem to which the movable is carried, or in the middle. And in those [motions] which are carried by nature, the rest is in the terminus ad quem; but in those which are carried violently or beside nature, the rest is in the terminus a quo; but in [things] thrown, in the middle. But of circular lation there is no terminus a quo, or ad quem, or middle; for neither beginning, nor end, nor middle is of it simply, for it is eternal in time, and at once drawn in length into itself and least interrupted. Wherefore, if there is no standing-still of the lation itself, neither will there be irregularity; for irregularity comes about on account of intension and remission.” And this is the first Aristotelian reason.
[Margin: 2nd reason of Aristotle. — 3rd reason of Aristotle.]
The second he subjoins (text 36), taken from the exclusion of the causes of irregularity. For, he says, since everything that is moved is moved by another, it is necessary that the irregularity of motion arise either from that which moves, or from that which is moved; but it can arise from neither head in a celestial body, because both that which moves and that which is moved is incorruptible and simple and altogether immutable. The third reason is adduced (text 37) thus: For either the whole period of the celestial motion would be unequal—now slower, now swifter—or the parts of it; but it has not yet been observed that the parts of it have become swifter or slower; for since an infinite time has preceded, in which this motion has existed, the distance of the stars would already have become infinite. But neither could the whole period be changed and become slower; for remission comes about on account of impotence [weakness], but impotence is beside nature; but in the first bodies there is nothing beside nature (for they are simple and unmixed, and in their proper region, nor is anything contrary to them); wherefore neither will there be impotence, and accordingly neither remission, nor intension—which connotes a remission before it, if not after it. Besides that, says Aristotle (text 38), it is absurd that, in an infinite time, that which moves be impotent, and again, in another infinite [time], potent; for all things in the infinite are indeterminate. It is plain, therefore, that the Aristotelian reasons hold not only about the motion of the prime Mobile, or of the supreme heaven, but about every motion of the Planets, which he thought to be circular and eternal (12 Metaphysics, text 43).
[Margin: Simple and Regular motion are not the same.]
But since (bk. 1 On the Heavens, text 23) he had said, “For of a simple body the motion must be simple,” and the Astronomers take “simple motion” for the mean between swift and slow—that is, for “equal [uniform]“—hence there flowed into the schools of the Physicists and Astronomers this, as a Peripatetic axiom: that of a simple body (such as the heaven is), the motion must be simple and equal, or regular. But this, certainly, Aristotle did not there [understand so]—
[…continues on p. 263 (PDF 298): “…for in the same text he at once subjoined: ‘But we say that these alone are simple — the [motion] which is circular, and the [motion] which is made along straight [lines]; and of the latter, two parts: one indeed from the middle [center], the other to the middle.’ Therefore the motion of the elements — which are themselves also simple bodies — [is simple, yet not equal]…” — i.e., Riccioli begins to dismantle the “simple = regular/equal” axiom.]
(printed p. 263 — completing the refutation of the “simple = regular” axiom: Aristotle himself counts the rectilinear motion of the elements among simple motions, yet teaches that such motion is irregular, growing swifter as bodies near their place of natural rest. Hence the Peripatetic axiom that a simple body like the heaven must move regularly and uniformly was badly derived from the name of “simple motion.”)
[Margin: Plato.]
Plato too, as Theon of Smyrna relates in his Astronomy, adhered to the Pythagoreans, and judged the celestial motions to be circular, regular, and equal.
[Margin: Ptolemy’s opinion.]
[II.] But of the Astronomers, the chief of them, Ptolemy (bk. 3 of the Almagest, ch. 3), expressly affirms that equality belongs per se to the celestial and perpetual bodies. For thus he begins that chapter: “But since it follows that we should demonstrate the apparent inequality in the Sun’s motion, it must be premised universally: that the motions of the wandering [stars] too, in consequentia of the signs [eastward], no otherwise than the lation of the whole universe in praecedentia [westward], are all, by their nature, equal and circular—that is, that all the lines which are understood to carry around the stars or their circles intercept, in all simply equal times, equal angles at the centers of any [given] circulation. But the inequalities which appear in them [the planets]—these come about on account of the positions and orderings of the circles by which they are moved, and [in which] they are enclosed in their spheres. Nor does anything foreign from their perpetuity in any way really come about, on account of the confused order of [their] appearances.” But he attributes the apparent inequality of the Sun either to our eye placed outside the center of the circle carrying the Sun (described from a [center] other than the earth’s center), or to the composition of a Concentric with an Epicycle carrying the Sun; wherefore, if our eye were in the center of the circle carrying the Sun, it would see equal portions of the Ecliptic traversed by it in equal times. And in bk. 9, ch. 2, he speaks thus: “But since it is proposed to us (as we did concerning the Sun and Moon) so concerning the five Planets too to demonstrate all their apparent inequalities to come about through equal and circular motions—for such motions befit the nature of the divine bodies, from which disorder and irregularity are far removed—we ought to value highly whatever we shall attain in this matter.”
[Margin: Fracastorius’s opinion.]
Ptolemy was followed thereafter by the Arabs, and very many Astronomers—whether asserters of Eccentrics and Epicycles, or of Homocentrics. For Fracastorius himself, in the Homocentrics (sect. 2, ch. 20), has these words: “But the revolutions of this inequality are not equal among themselves, neither the whole nor their parts, etc. But this is per accidens; for per se they are all equal, [especially] if they be measured by the mean motion of the first ‘circitor’.”
[Margin: Copernicus’s opinion.]
But how tenaciously Copernicus asserted the equality of the celestial motions, is gathered from this: that in Ptolemy he could not stomach the Moon and the five lesser Planets [to have], besides the Epicycle, two Eccentrics—of which one would carry the center of the Epicycle, but unequally, while the other would not carry [it], yet, with respect to its [own] center, the center of the Epicycle would be moved equally (which second Eccentric the Astronomers call the Equant, and about which [we treat] sufficiently in bk. 7, sect. 2, ch. 1, scholium 1). For Copernicus thought it absurd that the celestial motion should beg [borrow] its equality from a foreign center—that is, from that center from which the circle of such a motion was not described. The words of Copernicus (bk. 4, ch. 2) are these, about the Ptolemaic Lunar hypothesis: “The motion of the Epicycle in its Eccentric, which he describes, is therefore unequal. But if this be so, what shall we answer to the Axiom—that the motion of celestial bodies is equal, and doubtless at least seems equal—if the motion of the Epicycle, [though] appearing equal, were in reality unequal, and there will happen [something] utterly contrary to the established principle and assumption? But if you say that it is moved equally about the earth’s center, and that this suffices to safeguard the equality—what kind of equality, then, will that be, in a foreign circle, in which its motion does not exist, but in its own Eccentric? So indeed we wonder, etc.” And after a few [words]: “So too the Moon, traversing its Epicycle unequally—if now from unequals we should wish to prove the inequality of the appearance—what kind of argumentation that will be, one may observe. For what else shall we do, than that we shall give a handle to those who detract from this art?”—namely, Astronomy.
[Margin: Copernicus’s opinion.]
[III.] There was, therefore, with Copernicus, an axiom and principle now established and assumed as certain: that the motion of celestial bodies is equal—namely, per se, and the motion being regarded from the proper center of the circle. Nay, this Author was so addicted to the equality of the celestial motions, and so averse from that kind of inequality which Ptolemy had admitted in the five lesser Planets besides (the Equant circle being introduced into their hypothesis), that it was a goad for him to assert the motion of the Earth. For he himself professes thus (bk. 5, ch. 2): “The ancient Mathematicians, who held the earth immobile, imagined in Saturn, Jupiter, Mars, and Venus eccentr-epicycles, and besides another Eccentric, with respect to which the Epicycle would be moved equally, and the Planet in the Epicycle.” After which he describes their hypothesis (which we set forth with a clearer diagram in bk. 7, sect. 2, ch. 1). Then against them he infers: “But it is established that the equality of the Epicycle had to be made with respect to the center of its Deferent, etc.” Therefore here too they concede that the equality of a circular motion can be made about a foreign center, and not [its] proper [one]; similarly too in Mercury this happens more. But about the Moon, this has already been sufficiently refuted. These [things] and similar gave us occasion of thinking about the mobility of the earth, and other modes, by which the equality and principles of the art might remain, and the account of the apparent inequality be rendered more constant. Wherefore in this place too he [Copernicus] assumes, among the first principles of the Astronomical art, the equality of the celestial motion about that point which is the center of the circle, in whose periphery the motion is made—whether of the Planet, or of the center of the circle carrying the Planet.
[Margin: Reinhold’s opinion. — And Clavius’s.]
Nor did his follower Erasmus Reinhold the elder judge otherwise (in the preface to the Theorics of Peurbach), whose words—as embracing the opinion of many Astronomers—it will not irk [me] to recite: so, after the inequalities indicated which appear daily in the motions of the Planets, he subjoins: “Since, therefore, the variety of the celestial motions and appearances (which the Greeks call φαινόμενα [phainomena]) is so manifold, the Astronomers, with the highest diligence, with the greatest vigils and labors, have scrutinized the causes of appearances so dissimilar. For that so great a diversity in the motions of the Planets does not arise from a certain irregular motion of their celestial orbs (which carry the bodies of the Planets), as the unskilled imagine—the whole periods or revolutions of the orbs (which are established to be equable among themselves) manifestly cry out against [this], and convince [us otherwise]. Wherefore, of this so great irregularity, which is discerned in the parts of the periodic motions, the Astronomers hand down an erudite and plain cause: namely, that motions equable, and by their nature uniform, appear to us dissimilar—either because they take place in eccentric orbs, or also because, from many simple motions variously, as it were, compacted together at once, some one [motion] out of all these is made irregular.” Which author, further below, in the Theory of the Sun and in the scholium added to Peurbach’s Theory (p. 31), repeats things similar to the aforesaid: “We said above,” he says, “that, the observations of whole revolutions being collated, reason gathers that the motions of celestial bodies are altogether equable, constant, and fixed; but that, if the parts of any [single] revolution be compared among themselves, a varied and manifold anomaly is detected.”
But with much graver words, and a severer brow, our Clavius reprehends the men of the contrary opinion (on ch. 4 of the Sphere, p. 434), so that he does not hesitate to break forth into this sentence: “But the later men, and [those] of sounder mind, when they had begun to regard celestial things more rightly, more subtly, and more scrupulously, came into this opinion: that they pronounced it to be of the highest madness to think that in the motions of celestial bodies any irregularity, deformity, or inequality is found; but, on the contrary, that in them the highest equality, uniformity, and regularity ought to be posited.” And he goes on to confirm this—both a fortiori, from some motions of sublunary things (which, although they be perishable and mutable, yet keep a certain law and order in their motions); and from the Aristotelian reasons: namely, that in circular motion there is no beginning or end, by approaching which the approach must be made swifter and swifter (and therefore irregular); and that in the celestial movers there is no corruptibility nor impotence, from which a more remiss, and so—
[…continues on p. 264 (PDF 299): “…a slower, motion could happen [in the heavens]; finally, from the certain law of the periodic motion recurring into itself, by force of which the Astronomers most certainly predict the future conjunctions and syzygies of the Planets. And the same was the opinion of the Conimbricenses, Suessanus, Philalthaeus, Jandun, Albert of Saxony, Paul of Venice, Achillinus, Amicus…”]
(printed p. 264 — continuing the first opinion (for the equality of celestial motions): the page completes the argument that nothing in the heavens could cause a more remiss and slower motion, and appeals to the fixed law of periodic motion recurring into itself, by which Astronomers most certainly predict future conjunctions and syzygies of the Planets.)
[Margin: Other authors for the 1st opinion.]
And the same was the opinion of the Conimbricenses (2 On the Heavens, ch. 6, q. 2), of Suessanus [Agostino Nifo] (2 On the Heavens, text 40), of Philalthæus (ibid., text 35), of Jandun (q. 8), of Albert of Saxony (q. 13), of Paul of Venice (ch. 15), of Achillinus (1 On the Orbs, dist. 3), of Amicus (tract. 5 On the Heavens, q. 6, dub. 6; and q. 5, dist. 3, art. 1)—although they use a varied distinction; for some distinguish irregular motion from deformed and unequal [motion]. But all agree that, if the whole periods of one [and the] same planet be compared among themselves—for example, the Tropical Solar years among themselves, or the revolutions of Saturn among themselves—those are altogether equal, and the whole circle of them is accomplished in an equal time; but if the parts of one period be compared among themselves—say, the Northern semicircle, in which the Sun is, with the Southern semicircle—they confess that the motions are indeed unequal, because they are not made in an equal time; but they refer this very inequality to appearance (on account of the situation of the eyes of those observing these motions), or to the composition of several circles or partial Orbs, of which the individual ones, regarded in themselves, are indeed equal motions, but compose one unequal motion.
[Margin: Tycho’s opinion. — Bullialdus’s opinion.]
Finally, into the opinion of Copernicus Tycho was swept away, when (vol. 1 of the Progymnasmata, p. 11) he said: “But that all the celestial motions are per se regular and equable, and are carried circularly by a constant law, has long since been received by all Astronomers as an Axiom.” But—what you may wonder at more—Ismael Bullialdus, although he contends that the motions of the Planets are made through an Ellipse, not through a circle (and in this he would seem about to favor the physical inequality of the motions, which the inventor of this Elliptical way, Kepler—as we shall say presently—had built up), yet attempted to reduce this very hypothesis to equality; and therefore (in bk. [1] of the Philolaic Astronomy, ch. 13) he premises, among other principles, these six propositions:
1. That the Planets are moved by a single motion through a single line—which we have already shown. 2. That the revolutions of the Planets are equal, perpetual, constant, and uniform, and each [is] similar to all the prior and posterior [ones]; and the observations of all ages prove them such. 3. That they must therefore be regular, and composed of regular [motions]; 4. Because, being perpetual motions, they cannot otherwise [be] except circular, or [made] through a line returning into itself. 5. That they are composed of circular [motions], because they are accomplished by the laws of circles. 6. That the revolutions themselves have a principle of equality, which the Planet by its nature regards.
[Margin: 2nd opinion, for the inequality of the celestial motions. — Kepler.]
[IV.] The second Opinion, however, is that the motions of the Planets have a physical inequality, and not only an optical [one] arisen from mere appearance—so that, with respect even to some proper center of the orbit through which the Planet proceeds, there really, and from the nature of the Planetary motion, correspond to equal times unequal portions of such an orbit. So indeed Kepler (in the commentaries on Mars, ch. 22, 32, 33, 34, 39, 44, 57, taken together; and in the Epitome of Copernican Astronomy, bk. 4, part 3, and bk. 5, especially p. 711). Nay, even before [Kepler], Ptolemy in the Moon and the five lesser Planets admitted an Equant—that is, a circle, with respect to whose center the Planet or the Epicycle would be moved equally, but by which it would not be carried; wherefore in the Eccentric carrying the Planet he admitted an unequal motion with respect to its proper center, and so, as to this, a Physical inequality. (But about this Equant, and the distinction of Physical inequality from Optical, I here suppose many things already explained—bk. 3, ch. 2[1]; and bk. 7, sect. 2, ch. 1, scholium 1.)
[Margin: Cabeus.]
But our [own] Cabeus too (bk. 1 Meteorology, text 38, q. 2) teaches that the figures of the Astronomical hypotheses, by which the celestial motions are reduced to equality, are rather devised for our use, and as a foundation of geometrical calculation, than really exercised in the heaven; for he says (p. 221): “For just as a mean motion is not truly given, although it is necessarily supposed for the calculation, so neither is it necessary that a motion of the Eccentric or of the Deferent be given.” And (p. 222) he inclines wholly to the true and physical inequality of the motions. But for us, in a controversy of this kind, there is need of a certain distinction, so that we may open [reveal] our opinion, and [tell] for which [side] it is.
FIRST CONCLUSION
[Margin: 1st Conclusion, on the whole Period of the motions.]
Although it be probable, it is nevertheless not yet certain, that the whole periods or revolutions of the celestial motions are equal among themselves; nay, about the Moon it is certain that they are unequal.
[V.] What I said about the Moon is already known to Astronomers—nay, even to those skilled in the Ecclesiastical Computus.
[Margin: 3rd part of the conclusion is proved.]
For the period of the Moon—whether it be taken for the periodic month, in which it traverses the Zodiac, or for the synodic month, in which it is again joined to the Sun—is sometimes more than 30 days, sometimes less; and the variety of these months becomes manifest, more than once, in individual years; and about it [enough] has been said, more than enough, in bk. 4, from ch. 18. And so the third part of the conclusion remains proved.
[Margin: 1st part of the conclusion is proved.]
But the first part is proved, both by the authority of very many who think thus about this equality (some of whom—[speaking] from their own and many others’ opinion—I already adduced speaking at num. 3), and by reason: because an equality of this kind both per se has a beauty to be desired, and [because] the very small difference between the periods of the other Planets observed by [different] Astronomers is rather an indication of equality—but [an equality] not yet so perfectly known that all Astronomers must admit the same measure. But if God had willed the periods of those [planets] to be unequal, and [if] this were more befitting the nature of sublunary things and the perfection of the universe, then surely, at length, they would differ among themselves by some notable difference, and [one] manifest after some ages—just as has happened in the Lunar periods. So the motion of the Solar Apogee, which was unknown to Ptolemy on account of the small interval between his and Hipparchus’s observations (compared with the slowness of such a motion), at length nevertheless became patent after many other ages.
[Margin: 2nd part of the conclusion is proved.]
Furthermore, the second part of the conclusion is proved: because, although the period of the Sun, or the equinoctial Years, more probably are equal among themselves (as I taught in bk. 3, ch. 30), yet probable reasons of the inequality of the years are not lacking, which I adduced in the same place with their authors; and to this also contributes somewhat the so-diverse quantity found of such a year, which we exhibited in the synopsis (bk. 3, ch. 15, num. 9). But the inequality of the Solar period being posited [as] probable, much more probable becomes the inequality of the period of the other Planets, whose motions are bound up with the motion of the Sun and depend on it (as is plain from bk. 7, sect. 1, ch. 7); and besides, it becomes probable from the diverse opinion about their periodic motions, as is to be seen in the tables which I set forth in bk. 7, sect. 2 and 3, when I exhibited the various measures for foreknowing the Theory of the Planets according to different Astronomers. And so, not incongruously, John Anthony Delphinus (in the book On the celestial globes and motions, p. 53) infers, from the uncertainty of the Solar motion, the uncertainty of all the celestial motions. So, although the Period of the fixed [stars] more probably is equal (according to what I already said in bk. 6, ch. 17), yet that diversity of this period asserted by various Astronomers—which I reported in the same book (ch. 16) and represented in a table—makes its inequality probable; although, from a peculiar cause, its equality or inequality remains still uncertain, because not yet has one period of it been completed, and so not yet could either [alternative] be established by observation; for it requires far more than twenty thousand Solar years, and yet from the beginning of the World not yet have seven thousand years elapsed.
SECOND CONCLUSION
[Margin: 2nd Conclusion, on the parts of the Revolutions.]
Although the motions of the Planets are ordered, and regularly unequal in the parts of their periods; yet they are absolutely unequal—not only per accidens, on account of mere appearance, or on account of [their] composition from several equal motions, but per se, from the primary intention of God, and from the end for which they are ordered.
[VI.] The prior part of the conclusion, which is affirmative, is proved from the admirable symmetry of the partial motions among themselves, as far as it was permitted to detect by observation through so many ages; for they have such fixed laws that the Artificers [astronomers] have been able hitherto to reduce the motions of the Planets into Ephemerides, and to predict them long beforehand without an error which would be notable in most kinds of motions, or which could exclude Astronomy from the number of the practical sciences or arts—especially in these later ages.
[…continues on p. 265 (PDF 300): ”…For not for this reason do they lack fixed laws, that in predicting the Eclipses of the Moon and Sun there is still a tiny error; for, for this Art — in things so abstruse and so far removed from our regions — it suffices if such motions and aspects of the stars as the Astronomers predict from the Astronomical hypotheses and tables come to pass as nearly as possible [to the truth]…”]
(printed p. 265 — completing [VI.], the affirmative part of the Second Conclusion: the planets do not lack fixed laws merely because eclipse predictions retain a tiny error, for in matters so abstruse it suffices that predictions come to pass nearly and for the most part, safely enough for human uses. Hence the art is far more perfect in the minds of the presiding Intelligences, and the rules of these motions more certain in nature than with us.)
[Margin: Plato’s opinion.]
[VII.] But the assertion of the same prior part [of the conclusion] is confirmed from this: that not only the Writers of the true Religion, but the Gentiles too, from the order of the celestial motions, and the admirable harmony [concentus] by which, at fixed times, that inequality and discord of the motions is reduced to concord, rose up to acknowledge the Divinity of the Godhead, and the Providence of God, and to extol [it] with mild—but never sufficiently worthy—praises. So Plato in the Timaeus said: “But to us it is to be asserted, for this reason especially, that God begot eyes—that, having beheld the circuits of mind which are accomplished in the heavens, we might apply [them] to the use of our [own] mind, and might recall the discoursings of our knowledge (akin to those [celestial circuits], but in a way perturbed) to the temper [evenness] of those [celestial ones]. And when we have recognized them, and—endowed with right reason according to nature—have perceived the order of the individual [motions], let us imitate the conversions [revolutions] of God, which are carried on without any error, and compose the vague and erratic discoursings of our thought after the example of the gods.” He calls the moving Intelligences of the heavens “gods”; and their motions he calls “conversions of God himself,” inasmuch as [they were] first instituted by him and ordered with the highest harmony.
[Margin: The opinion of Plutarch, and again of Plato.]
But more clearly does Plutarch propose Plato’s opinion (bk. 1 On the Opinions of the Philosophers, ch. 6), where, when he had said of mortals in general: “But they had a notion of God taken first from the beauty of the things which are beheld; for nothing beautiful is made rashly or by chance, but it is made by the use of a certain art that sets [things] in harmony; and that the world is beautiful is plain from [its] form, color, magnitude, and the variety of the stars surrounding the world”—he subjoined, after the mind of Plato (whom he there praises): “And those things which are conspicuous in [the heaven] complete the beauty of the heaven; for the oblique circle [the Zodiac] is distinguished with various images.” And, the signs of the Zodiac being enumerated, he concludes: “Innumerable others of this kind the same God scattered through the convexities of the heaven; whence Euripides says: the starry splendor of the heaven—Chronos [Time], honorably distinguished, the work of a skilled craftsman. Truly, we have hence greatly taken a knowledge of God; for with a perpetual tenor the Sun, Moon, and the rest of the stars, having sunk beneath the earth, come up again of one [same] color, and besides of equal magnitude, from the same places, and at exactly the same time.” Excellent, but more prolix, are the [things] which Cicero (bk. 2, On the Nature of the Gods) declares to this argument.
[Margin: Seneca’s opinion.]
And so let us hear Seneca, beginning thus the very first chapter On Providence: “You asked me, Lucilius, why, if the world is governed by providence, many evils happen to good men. This we would more conveniently prove in the context of the work, when we should prove that providence presides over all things, and that God is concerned with us.” And presently he premises this as a most well-known argument: “It is superfluous, at present, to show that so great a work does not stand without some guardian, and that this fixed coursing of the stars is not [the work] of a chance impulse; that this unoffended [smooth] velocity proceeds by the command of an eternal law; that [the heaven]—bearing so many things on land and sea, so many of the brightest lights, and shining in such a disposition—[that] this order is not [the order] of erratic matter, nor do the [things] which have come together by chance hang together by so great an art.” But nothing more magnificent could be said than was said in Psalm 18 [19]: “The heavens declare the glory of God, etc.”—where Lorinus our [Jesuit] is especially to be seen; and in Job 38, by God himself: “Dost thou know the order of heaven, and wilt thou set down its reason on the earth?” and a little below: “Who shall declare the reason of the heavens, and who shall make the harmony [concentus] of heaven to sleep [be silent]?”—where Pineda [is to be consulted]. And so not undeservedly does St. John Chrysostom (homily 10 to the people) call the heaven βιβλίον μέγιστον καὶ ἰδιώταις καὶ σοφοῖς—a greatest book, open to the unlearned and to the wise. And Minucius Felix (in the Octavius) says: “You see the heaven itself: now you will know how great is, in it, the wondrous and divine balancing [libratio] of the supreme governor.” But more about this book written in golden letters, see in St. Basil (Hexaemeron, homily 11) and Nicephorus (bk. 11 of the Ecclesiastical History, ch. 43).
[Margin: 1st argument for the 2nd part of the conclusion.]
[VIII.] The posterior [latter] part of the Conclusion is shown thus. First: although inequality without any order, rule, and rhythm is a certain imperfection, yet an inequality [that is] ordered, regular, and having rhythms and recurrences of the motions at fixed times, is a great perfection, and has far greater beauty than simple equality; therefore this rather befits the celestial motions—or at least this too ought to have been in the heaven, and not equality only—so that in the fixed stars indeed (which most imitate the prime mobile), as to the motion of longitude there would be no inequality, nor as to latitude from the Ecliptic, nor as to their distance among themselves or from the center of the World, but there would be only some variation (yet very slow) in the motion of declination. On the contrary, in the Moon (which is nearest the earth, and closest to the sphere of changeable things) there would be the greatest inequality. But in the Sun there would be only a middling inequality—namely in the motion of longitude, altitude, and declination—but not in the motion of latitude (since it is without latitude), nor in the motion of libration about its axis, nor that variation or second anomaly which is in the Moon and the other Planets; among which the two nearer to the Fixed [stars], Saturn and Jupiter, have obtained a smaller inequality than those which are below the Sun and become nearer to the Moon; and of these very [latter ones], which are more tightly bound to the Sun and do not depart from it by a whole semicircle, Mercury and Venus have obtained a smaller inequality than Mars.
The antecedent [of this argument] is manifest by an induction made from all the most beautiful things, whether they come about by nature or by art. For as to nature, neither the bodies of animals, nor the branches, foliage, leaves, [and] flowers of plants, keep an equality of members or of parts—whether in figure, or in quantity, or in color—but [keep] only a symmetry, and a consent [agreement] of unequal parts, with incredible variety. Nor are all fruits—nay, scarcely any—spherical or cubic, nor do they affect the mathematical beauty of any regular figure; and scarcely among minerals [fossils] would you find one or two which have a regular figure from nature. The spaces of the lands—and, as it were, the plots [beds] of this great garden—and the spaces of the seas within them: did God, from the beginning of the world, force [them] within the limits of a circular, or quadrangular, or triangular figure? By no means indeed. But as to artifacts, although the beauty of some requires a certain equality in figures or motions, yet the greater part requires inequality and disparity, measured out by fixed rules. This is to be seen in Architecture, in Sculpture, and Painting, and the like; this in the liberal arts; this, finally, in every kind of Music—which makes for our matter—shines forth especially: for if you should try to reduce its motions and sounds to equality, or to deduce their laws from the equality of the parts (as if [the parts] regarded that [equality] primarily per se), [take care] lest you snatch from them all the sweetness of the harmonies, and destroy the soul of harmony. For what is wont to be tolerated as more unpleasant, and with greater tedium, than monotony and uniformity in singing and in modulation? Or what [is] more inelegant than if dancers to the beat [number], or [those] striking the cithara, primarily per se aimed to describe a circle, or some figure, with equal motions?
[Margin: 2nd argument, from the figures of the stars, the aspect [phases] of the Moon and Planets, and the spots of the Sun.]
[IX.] Secondly: if to a celestial body—because it is supposed to be simple—there were due, per se, an equality of motions and a most simple uniformity, then to it also would be due a beauty of regular figures in the disposition of the Stars, and a most exactly spherical figure of the Planets without any roughnesses, and a most shining splendor and brightness without any spots, and finally a perpetual light without any vicissitude of obscuration. But we discern the opposite—as many of us as look up at the heaven, whether with naked eyes or armed with a Telescope: for the configurations of the Stars are so far removed from regular figures that, if you except one or two triangles (and that not equilateral but Isosceles), the other stars might seem to be sown by chance and at random through the fields of the heaven, and very many [are] to be numbered among the σποράδες [sporades, the “scattered” stars] and the ἄμορφοι [amorphoi, the “shapeless” / unformed stars]—unless this incredible variety had at length become patent, to those contemplating these [things] deeply, [as] serving in a wonderful manner Agriculture, Navigation, Medicine, [and] Astronomy itself. The roughnesses in the globe of the Moon, and either the roughnesses or the spots in the face of the Sun, in the bands of Jupiter, and in the boss [umbo] of Mars, and finally the Eclipses of the satellites of Jupiter, and the overshadowings of Saturn by its attendants [the lateral bodies]—now in our age—
[…continues on p. 266 (PDF 301): “…the Tube-glass [telescope] has revealed [these things], not a fiction of Prometheus’s wand, but a most true experiment of the Tube-glass; and yet from these very [things], no otherwise than from the Eclipses of the Moon and Sun, there arises a greater elegance and beauty than if all things had been disposed in the heaven in a simple and uniform manner. [X] Thirdly: the End to which the celestial motions are ordered requires in them some inequality (yet regulable and ordered)…”]
(printed p. 266 — completing [IX.], the second argument, on the telescopic evidence: what the telescope has revealed in our age is no fiction but a most true experiment; and from these very irregularities, no otherwise than from the Eclipses of the Moon and Sun, there arises a greater elegance and beauty than if all things in the heaven had been disposed in a simple and uniform manner.)
[Margin: 3rd argument, from the End.]
[X.] Thirdly: the End, to which the celestial motions are ordered, requires in them some inequality—yet regulable and ordered—namely, the diversity of effects in sublunary [things], and the incredible variety of influxes, and of changes to be effected for the sake of living and animate [beings], but especially for the sake of man, who from it [this variety] was going to obtain far more goods, and far more abundant matter for praising and loving his Creator, who is the End of all. And so, that for this variety the inequality which I have spoken of is a more apt means than mere equality, is too manifest to need proof.
[Margin: The heaven and the Stars were made for the sake of men.]
But that the heaven, and [whatever is] sensible, and whatever stars shine for us in it, were created for the sake of men—[this is so], whether the Epicureans will or no, and certain Copernicans (who [would have] the Earth rather [go] around the Sun than the Sun and all the stars around us, and around the immobile Earth as a center, act—will, I say, or no, it is true). For not only does Aristotle say (2 Physics, text 23), “for we too are in a manner the end of all things”; and (1 Politics, ch. 5) “that nature made all things for the sake of men”; and Cicero (1 On the Laws). But the infallible authority, divine Scripture, by this most valid argument, tries to deter men from [giving] divine worship to the stars; Deuteronomy 4 says: “Lest perhaps, [thy] eyes being lifted up to heaven, thou see the Sun and Moon, and all the stars of heaven, and, deceived by error, adore them, and worship the things which the Lord thy God created for the service of all the nations that are under heaven.” For what is more foolish than that, by a man (to whom the supreme Lord has granted a certain useful dominion over the visible creatures), worship and adoration should be displayed to His ministers and handmaids? For God, as is held in Genesis 1, placed the stars in the firmament of heaven not that they might shine for themselves mutually, [or for] the heaven [alone], but “That they might shine upon the earth”; where Lippomanus rightly [says], in the Catena: “But if for this reason they were placed by God—that they might illuminate the earth—then not [were they placed] that they might lord it over man; for [God] is the Lord, who created them for the use of men.” Likewise the sacred interpreters can be heard on that [text] of Psalm 8, where, when David had said, “For I will behold thy heavens, the works of thy fingers, the Moon and the stars which thou hast founded,” at once, astonished that God has subjected these too to man, he exclaimed: “What is man, that thou art mindful of him, or the son of man, that thou visitest him? etc. And thou hast set him over [all] the works of thy hands.” Which [words], although they must be understood especially of Christ—at least in the mystical sense, to whom it more properly belongs to be “the son of man,” that is, of the Virgin Mary alone (since the others are sons either of no man, like Adam and Eve, or of two men; and so St. Paul understood [it])—yet, to the letter, not a few Fathers teach that [it] can be taken of any man whatever (as is to be seen in John Lorinus on that Psalm); and some [teach] that the former part, “What is man?”, pertains to every man, and the latter, “or the son of man,” peculiarly to Christ. And certainly to men pertains that [text] of the Apostle (1 Corinthians 3): “All things are yours, whether the world, or life, or death, whether things present or things to come.”
[Margin: St. Chrysostom’s opinion.]
But that those who deny the stars to have been made for our sake favor the error of the Gentiles, I gather from St. John Chrysostom (homily 6 on Genesis), saying: “For let us teach those preoccupied with the Gentile [error], with all gentleness, lest they confound the order, and—the Creator being abandoned—adore the creatures which were made for our salvation and utility; and if what we teach displeases the Gentiles, do thou nevertheless cry out with a clear voice that for the sake of the human race all these were made; for the Maker had need of none of these things for himself, but, that he might show toward us his indulgence and benignity, he produced all these—showing with how great honor he attends the human race, and that, led by the hand by these [things], we might ascend to an adoration befitting him.” But here this golden Doctor was explaining the Work of the fourth day, and the formation of the Luminaries and stars.
[Margin: Lactantius’s opinion.]
But Lactantius too (the book On the Wrath of God, ch. 13 and 14) [teaches] that the heaven was made for our sake; just as St. [Gregory of] Nyssa too (the book On the Formation of Man, ch. 1 and 2) teaches; and (bk. 7 of the Divine Institutes, ch. 3 and 4) he [Lactantius] inveighs not only against the Epicureans, denying that the world was made for our sake, but also against the Platonists, who indeed asserted the Providence of God, [but] did not expressly teach that the World was made for our sake—which, however, the Stoics taught: “It was necessary, therefore,” he says, “for Plato too, and those who thought the same, to teach and explain what cause, what reason, there was for fabricating so great a work—why, or for whose sake, he made this. But the same Stoics say [that] the world was made for the sake of men.” And a little after, against Plato (who asserted the future eternity of the world), he argues against this [view]: “If for the sake of men the world was made, and so made that it should be eternal, why then are they, for whose sake it was made, not everlasting? If [they are] mortal, for whose sake it was made, then it too [is] mortal and dissoluble; for it is not of more [worth] than those for whose sake it was made. And again: But whoever denies that it was made for the sake of men—he holds no reason [account]; for if he says that the Maker himself wrought these so great works for his own sake—why, then, were we born? why do we enjoy the world itself? why do we intercept goods belonging to another? etc. Doubtless God willed to be seen [to appear], and to fashion, by his various images (as it were, seals), with which he might delight himself; and nevertheless, if it were so, he would have care of living beings, and especially of man, to whose command [empire] he subjected all things.” But as to what the same Lactantius says (ch. 4), “The world, therefore, [was made] by God not indeed for his own sake—for he needs neither the heat of the Sun nor [its] light, etc.; and all these things which are in the heaven, and which are generated, God himself does not use”—[this] must be corrected; for indeed, “The Lord has wrought all things for his own sake,” as is said in Proverbs 16. And so Fromondus, in his Vesta, rightly teaches from Tertullian that “both the stars and the elements serve [are subservient to] man”; and John Baptist Morin, against Lansberge, observes that it was fitting for God to regard the utility of men, and not only the facility or shortcut [economy] of nature in these motions; and Fr. Nicholas Zucchi (in the new Philosophy On Machines, part 5, sect. 11) is angry against those who strive to suppress this truth, Scripture and the disposition of the whole universe resisting. Nor let it seem to anyone too much, that such vast and sublime bodies were made for the sake of men: for since they were made that the contemplating creature might thence acknowledge and adore the Creator—and [since] the Angel, being himself without senses, would not need the beauty of the sensible world for that—it remains that all these sensible things were made only for the sake of men; but man himself, and all things, for the sake of God.
[Margin: Andreas of Jerusalem.]
Wherefore, significantly, Andreas of Jerusalem said (in the sermon On the Angelic Salutation) that man is [the one] for whose sake God οὐρανὸν [ἐδημιούργησε] [created the heaven], etc.—that is, established the heaven, made firm the earth, spread out the air, widened the seas, and finally made the whole [mass and fabric] which is subjected to the eyes [a thing] to be looked up to.
[Margin: St. Augustine. — Arnobius.]
And therefore elsewhere he calls man μέγα τῆς ἐργασίας κατόρθωμα—namely, a vast specimen [masterpiece] of the divine operation; and by St. Augustine (sermon 225 On the Season) it is said: “Man, the dear and friendly possession of God; man, for whose sake the heaven was made firm.” Nor say that it seems unfitting that this greatest World, and the immense mass of the heavens, was made for the sake of a three-cubit little manikin: for although man was called by the pagan Philosophers μικρὸς κόσμος [mikros kosmos, a little world], and is smaller in mass than the heaven, yet in the perfection of [his] nature and in rational nobility he is more august and greater—which Arnobius indeed touched on (bk. 2 Against the Gentiles), in these words: “This is that precious [being], the man endowed with most august faculties, who is called a lesser world, and is wholly fashioned into the species of [God’s] likeness.”
[Margin: Hermias. — St. Gregory Nazianzen.]
Nay, from Protagoras’s opinion, Hermias (in [his] Mockery of the Gentiles) called man ὅρος καὶ κρίσις τῶν πραγμάτων—the boundary [terminus] of things, [their] judgment and norm; but expressly St. Gregory Nazianzen (oration 38) denied that man is a μικρὸς κόσμος (a little world), and rather called him μέγας κόσμος ἐν μικρῷ—a Great world in a small [compass]. But to whom would it seem wonderful or incredible that the heaven and stars were made for the sake of men—if the Son of God (as the Church professes in the Creed), stooping under the burden of [his] immense benefit, sings: “Who for us men, and for our salvation, etc.”; and in that sweetest hymn: “Given to us, born to us”?
[Margin: Synesius. — St. Ambrose.]
And so cleverly Synesius (Epistle 57) [says] of man: “τίμιον ζῷον ὁ ἄνθρωπος,” etc.—man is a precious animal, if for his sake Christ was lifted up on the cross. And on Psalm 118 [119] St. Ambrose calls him “the Precious work of God”; and in the book On the Good of Death: “The whole world is a small [thing] for the loss [expenditure] of one soul.” Finally St. Gregory of Nyssa (homily 4 on Ecclesiastes) affirms that not even the whole world is ἄξιον τῆς ψυχῆς ἀντάλλαγμα—a worthy price [exchange] for the soul.
[…continues on p. 267 (PDF 302): “Let Lucretius, then, be gone — [Lucretius] of Epicurus’s herd, wont to grunt rather than to sing — when he dares to say: ‘To say, moreover, that [the gods] willed to prepare, for the sake of men, the splendid nature of the world, etc., is to dote; for what [profit is it] to the immortal and blessed [gods]…’ ” — then Riccioli turns to the remaining proofs/objections of Chapter IV.]
(printed p. 267 — completing [X.], the argument from the End: the argument closes with a dismissal of Lucretius, of Epicurus’s herd and wont to grunt rather than sing, before quoting the verses he dares to utter.)
“To say, moreover, that [the gods] willed to prepare, for the sake of men, the splendid nature of the world, etc., is to dote [be foolish]; for what [reason is there] that the immortal and blessed [gods] should undertake to do anything for our sake?”
I recognize, indeed, that there will be [those] who now think me to be wandering outside [the subject], and to be playing the preacher or the ecclesiast rather than the Astronomer; but they will now have to consider, from what has been indicated, that these darts are directed by us against two kinds of enemies. One is [the kind] of those who, attributing to the Earth the annual motion, will not have it to be the center of the celestial motions, nor [will they have] the stars [to be ordered] for the sake of the living beings placed on it—nor even for the sake of man—in such a way that the earth and man do not also, together with it, as a Planet’s inhabitant, revolve around another, more principal, body in the world; and for this cause they make light of this doctrine of the Heaven and World made for man’s sake. The other kind is [that] of those who, too much addicted to the equality of the motions, when they see them to be unequal with respect to the earth (or the center of the world, from which they are regarded by us), deny that their motions are per se ordered to this center, or for our sake.
[Margin: A compendium of the third argument, and [its] double force.]
Against these, therefore, we hurl this twin argument—but set forth more loosely—thus gathered, as it were, into a throwing-strap for [casting] in few [words]: “The motion of the heavens and stars, with respect to the men observing [it], is unequal; but the motion of the stars per se—that is, from its primary end and the chief institution of God—is unequal; therefore it is per se, and not only per accidens, unequal.” And again: “The motion of the heavens and stars, in order to the variety of effects which the sublunary [things]—for man’s sake—and man himself especially, were to enjoy, had to be unequal; but the same motion per se is ordered to the variety of these effects, and especially for man’s sake; therefore this motion per se had to be unequal.”
[Margin: 4th argument, from the order of the parts to the whole.]
[XI.] Fourth: It is admitted among the Astronomers (the defenders of the equality of motions) that, if the whole composite motion of the Planets be regarded, it is unequal—inasmuch as accomplished through diverse circles described from diverse centers; but [they hold] that, if the motions of the individual circles be regarded separately and singly—say, the motion of the center of the Epicycle in the Eccentric, and the motion of the body of the Planet in the Epicycle—they are simple and equal about their proper centers. Now I argue thus: The motion of the parts is not for the sake of the parts themselves, nor per se in comparison to the whole; but per se it is for the sake of the whole; or at least, comparing parts and whole, that which is had per se [as primary] is rather the whole itself, as the end and [as] a perfect thing. But the whole motion, arising from these partial motions, is unequal, granted that the partial [motions] are equal. Therefore the motion of the Planets is per se unequal.
[Margin: 5th argument.]
[XII.] Fifth: If the motion of the stars were per se equal—inasmuch as regarded in order to [its] proper center—it would be necessary that it had been ordered by God to that center, as to some good and [something] more excellent than the movable [body] itself. For if you say that equality befits them for the sake of themselves, not for the sake of the center—this is what is in dispute, and ought not to be assumed as conceded; nay, rather, they [the stars] are of themselves indifferent to motion around this or another point of the universe. Wherefore, if in their motion they per se depend on one point, which is the center of their circle, then surely [they depend] on it—either as an end, or as an efficient and influent [cause]—and acquire perfection [from it]. But neither the center of the Eccentric nor the center of the Epicycle has any dignity in the universe, nor any force for influencing the stars (unless someone gratuitously and rashly fabricate it), but they are unstable points in the universe, and of no quantity, not to say excellence. Incongruously, therefore, is the quality of the motion of the heavens estimated from [its] order to points of this kind; and so equality per se, founded on these, has an unstable foundation, and [one] of no moment.
[Margin: 6th argument, from the situation of the observers and from the senses.]
[XIII.] Sixth: If the apparent or optical inequality is per accidens—because our eye is now outside the center of the circle through which the Planet is moved, and no eye is in the center of the Eccentric or Epicycle, whence it could regard the motion such as it is per se, and as it ought to be regarded—then that perfection [the per se equality] lacks a spectator, and only the imperfection (that is, what is per accidens) has had a spectator; but this seems to derogate from the divine omnipotence. But if you say that God gave to man not only the eyes of the body, but also [the eyes] of the mind, that by reason he might gather, from the inequality of the apparent motion, the theory of a motion per se equal—on the contrary [I say it is so], because the presumption [possession], in this judgment, stands for the senses; and unless from elsewhere the intellect be evidently or certainly bound to correct the judgment which, relying on the senses, it made about these motions, it must pronounce for the senses, and estimate these motions to be such as it is established they have been detected to be by the constant experiment of the observations through all the ages—namely, unequal. Granted that, for the ease of calculation (on account of our weakness), we may feign mean and equal motions, and use, for declaring them, perfect circles—that is, circular motions made equally about their proper centers—yet this equality (or rather, this fiction of equality) holds per accidens in this art; therefore the inequality [holds] per se.
[Margin: 7th argument, from rectilinear motion.]
[XIV.] Seventh: Some celestial motions are made through straight lines, or chords of circles, according to Copernicus, Maginus, Longomontanus, [and] Lansberge—as are certain librations; and yet, in order to safeguard equality, they take a law from a circle, and those motions are feigned [as] made in a circle, when nevertheless they are not [so]; therefore, if the path itself, through which they are really accomplished, be regarded, those motions are per se unequal. And the same argument holds of the motion made through an elliptical circumference, according to Kepler and Bullialdus; for the Planets really, as these two Astronomers will have it, are carried through the circumference of the Ellipse unequally—granted that Bullialdus adds [that], through any two extremes of the ordinates in the Ellipse, circles can be drawn, and from them some ratio of equality be taken: for the Planet does not proceed through those circles. Then [also], it is one thing to be moved per se equally—which we deny to the stars—and another [thing] to take, from an external circle, laws not of equality, but of a motion [proceeding] by some regular increment or decrement (which could be conceded): as if a movable be carried through a straight line, but with that variety which the sines, or secants, or tangents, require, according to an equal number of degrees taken in an equal time. But hence it would rather follow that that inequality is per se intended; because, for the sake of preserving it—but [preserving it] with some rule—a feigned motion, equal, through a circle, is assumed from without. Just as, if for describing an Ellipse or Parabola an instrument were made which—turned about in some part of itself through a circle—would be apt for describing an Ellipse or Parabola, surely the Ellipse and Parabola would be intended per se as the end, and the motion through the circle as the means. So too, [though] the Harmost [tuning-master], or chief-Musician, by equal elevations and depressions of the hand, in equal time, measures out the tempi for the singers, yet per se he intends that they—according to the musical notes—raise and lower, lift up and depress, hasten or retard [the voice], and per se regards the inequality of the harmony, not the equality of the beat.
[Margin: 8th argument, from the motion of the Fixed [stars].]
[XV.] Eighth: The motion of declination of the Fixed [stars], and the variation of the right ascensions, is unequal, nor is it varied equally in an equal time, as is known from the Problems of the prime Mobile; and yet it is such [unequal] in order to [its] proper center, and follows necessarily from the equal motion of longitude; nor can it be said, with foundation, that this [declination motion] is per accidens intended, but the motion of longitude per se. As, therefore, this motion is per se unequal, so can others be in the heaven.
[Margin: 9th argument, from reconciling the Planets’ motion with the Prime Mobile.]
[XVI.] Ninth: There is no better and simpler reason for reconciling the proper motion of the Planets with the motion of the Prime Mobile than through spirals and helices, as we taught in ch. 3. But the Planets are not ordered to a single center; rather, they are screw-wise [cochleatim] loosened and restrained, raised and cast down in various ways. Therefore that equality, taken from perfect circles, is not per se intended by Nature and God.
[Margin: An objection is dissolved.]
[XVII.] Furthermore, the adversaries asserting that it is an Axiom long since received in the Schools of Physics and Astronomy—that of a simple body (such as is any celestial body) the motion too must be simple, that is, equal—it would be answered that this is true of the motion of the Prime Mobile, or [true] indeed of the motion of the Secondary mobiles, if equality be taken as it is opposed to irregularity and randomness, that is, to the disorder of the motions. Otherwise [if it means uniform speed], it is denied to be an axiom; or at least it is conceded, but [only] of a body which is simple not only in its being, but also in the character of [its] cause, or in its effects—in neither of which ways are the heaven or the stars simple. Furthermore, Aristotle’s reasons are merely topical [dialectical], nor do they contain an adequate cause of the inequality in the motion; for that [inequality] can arise from elsewhere than from the end, and the terminus in which the movable seeks to rest, or—
[…continues on p. 268 (PDF 303): “…than from the impotence of the mover, or from the resistance of the subject which is moved, as is plain.” — and so Chapter IV ends; then CHAPTER V opens (whether the Intelligences geometrize or calculate).]
(printed p. 268 — completing [XVII.], the close of Chapter IV: the page opens mid-sentence, concluding that the inequality of celestial motions can arise from causes other than the impotence of the mover or the resistance of the subject moved.)