(xt) ‘so that what reason is thought to have of the divine belongs to the prime mover (éxetvov, cf. éxelvos |. 27) rather than to the human mind’, s¢. since it always éyeu 76 vontov while we only sometimes do so. Then 7 Oewpia = ‘ God’s contemplation’.
(2) ‘so that this (actuality) rather than that (potentiality) is what reason is thought to have of the divine’. This derives some support from 1074? 21 étu 8€ etre vods 4 odota avTod cite voynois éort. Then 4 Gewpia will mean ‘actual contemplation’ in general. So Bz. takes the passage.
If éxetvo paAdov rovrov be read the meaning must be ‘so that that which reason is thought to have of the divine belongs to the prime mover (rovrov) rather than to the human mind’, This is slightly less natural than the two interpretations above.
24. For 4 Sewpia as the actuality, opposed to émornun, the poten- tiality of knowledge, cf. @. 10488 34, 1050%12-14, Phys. 255% 34,
De An. 412% 11, 23, 417% 29, G. A. 735211, L. WV. 1146 31-35. lob oUTws eb éxel, ds Hpets ToTd, 6 Beds del resumes what was said in Il. 14, 15.
25. ci S¢ paddov. That God’s voyors is always better than ours ever is has not been proved, but has been suggested in the words 7 dé vonows 4 Ka abryy (1. 18), where the self-dependent voyois of God is contrasted with the human ydyo1s dependent on sense and imagination.
26. For #e retrospective cf. ® 26,
28. Bz.’s conjecture 84 for d¢ greatly improves the sense, and is supported by Them. 24. 19.
32. Sia 7d kal Tov putay KTh., cf. N. 1092 12.
382 Commentary
35—1073" 3. Cf. @. 1049) 17-27.
1073? 3-» 17. Blass has pointed out that in this whole passage there are only two hiatuses (# 26,,34), that > 17-38 is almost free from hiatus, and 1074* 38-? 14 contains only one (> 7), while 1073? Ahora 1074® 38 is full of hiatuses. He points out further that otro in 1074» 3 does not refer naturally to anything that immediately precedes. He infers that Aristotle has here incorporated, with additions, extracts from an earlier and less scientific work of his own, in which much more attention was paid to style. This view can, however, hardly be right. At least the reference to Callippus’ theory (1073 32-38), and probably the whole discussion of the concentric spheres and their movers (1073 14—1074? 14), belongs to the latest period of Aristotle’s life. Cf. n. at beginning of ch. 8.
5, déSektar, Bz. thinks the reference is to Phys. 26717, but Aristotle’s mode of reference to a separate book is almost invariably fuller than this (cf. 10724 n.), and, since the first 67. clause (3-5) and the third (11, 12) clearly refer to the results of the immediately pre- ceding argument, it is pretty certain that this one does so too, Aris- totle has not, strictly speaking, shown that the przmum movens is without extension, but he has proved something from which it readily follows (cf. Il. 7-11), and dédexrar expresses this fact, though rather loosely.
7. obdev 8 exet Svvapu & diretpov metepacpevoy, Cf, Phys. 2662 24 6,
10. dAws ovK EoTiv Obder daretpoy peyeDos, cf. Phys. iii. 5, De Caeloi. 5.
12, waco. yap at d\dar Kuvyjoers FoTepar THs KATA TéToy, Cf. 1072) 8, 9.
The number of the eternal moving principles (ch. 8).
1073714. Our predecessors have not been precise about this. The ideal theory does not discuss it. It identifies Ideas with numbers, but sometimes treats them as unlimited, sometimes (but without sufficient proof) as limited by the number ro.
22. We can use previous premises and distinctions. The first principle is an unmoved mover which causes one primary eternal motion. Since every eternal motion requires an eternal cause, and there are other eternal motions (viz. those of the planets) besides that of the first heaven, each of these requires an eternal substance as mover. It must be substance since the moved is a substance, mover is prior to moved, and only substance can be prior to substance. There must be as many such substances as there are motions.
bg. Their number must be determined by astronomy—the most akin to philosophy of the mathematical sciences—since it alone of these sciences deals with concrete substance. It is obvious that the
motions are more numerous than the moved bodies. We proceed to give a sketch of the accounts of various mathematicians.
17. Eudoxus assigned three spheres to the sun and three to the moon,
(1) a sphere having the daily rotation of the fixed stars,
(2) a sphere having a yearly motion along the zodiac,
(3) a sphere having a motion across the zodiac (stretching across a greater breadth of it in the case of the moon).
He assigned to the planets (1) and (2) and
(3’) a sphere whose poles are in the ecliptic (the poles being the same for Venus and Mercury),
(4’) a sphere moved obliquely to (3’). Total 26.
32. Callippus kept the same order, and the same number of spheres for Jupiter and Saturn, but added two each for the sun and moon, and one for each of the other planets. Total 33.
38. We must suppose, for each of these bodies except the moon, counteracting spheres, one less in number than the positive spheres, to neutralize their action on the outer sphere of the next system (counting
inwards). Total 55.
Or if we do not add the said motions to sun and moon, we get
Total 47.
107414. This is also the number of the unmoved movers (prob- ably—we do not claim certainty). If there can be no motion which does not contribute to the motion of a star, and every substance which is impassive and in itself has attained the best is an end, this must be the total number of the unmoved substances. For if there are others, they must cause motion as ends of motion. But there cannot be other motions than those named. This is made probable by study of the moved bodies. For no motion is for its own sake or for the sake of another motion, but for the sake ofthe stars (otherwise there would be an infinite regress).
(31. The physical universe is one. For if there were many, each would have a different individual cause, and therefore the causes would have to have matter; for, as far as form goes, it is common to many individuals. But the prime essence has not matter; for it is actuality. Therefore the prime mover, and therefore also the universe which it moyes, is one in number as well as in definition.)
38. There is an old tradition that the stars are gods. The rest of the tradition has been added to lend sanction to the laws and on utilitarian grounds—i.e. the anthropomorphic or zoomorphic parts of the mytho-
384 Commentary
logy. But the original part, that the prime substances are gods, is in- spired, It is a relic of that completest possible development of the arts and sciences, which must have been often achieved and often lost.
Jaeger has argued forcibly (Aris¢, 366-392) that while most of Bk. A is early, this chapter must have been written quite late in Aristotle’s life. The theory of Callippus referred to in 1073 32-38 as a thing of the past (ériOero, 1. 33) can hardly be earlier than 330-325. The chapter interrupts the discussion of the first mover in chs. 7, 9. It is written in a full and careful manner, very different from the jottings which form the rest of the book. The doctrine of the ‘intelligences’ which move the spheres is hardly consistent with the doctrine of the single first mover in ch. 7 (cf. 1072» 13 f.), and is late—still absent in the De Motu Animahum and only tentative in Physics viii (258 10-12, 259° 3-15). 1074 31-38 seems to be a fragment belonging to the earlier and more monistic period of Aristotle’s thought.
1073* 16. For émopdcers = arodpavoes, cf. Rhet. 1365) 24.
20. dté 8 ds pexpt Tis Sexddosapropevwv. Thisviewis ascribed to some of the believers in ideal numbers in M. 1084° 12, to Platonists gener- ally in 1084 31, and to Plato himself in PAys. 206 32. The doctrine was derived from the Pythagoreans, for whom cf. A. 98628; Philolaus fr. 11.5; Theo Smyrn. pp. 93. 19, 25, 99. 8, 106. 7 Hiller; Zheologum. Artthm. pp. 60, 61 Ast; Photius, 4747. p. 439%5 Bekker; Zeller io 504-505; Burnet, Z. G. P.§ 48. Speusippus connected one with the point, two with the line, three with the plane surface (the triangle), four with the solid (the tetrahedron) ; and 1+2+3+4 = 10 ( Theo- logum. Arithm. p. 63 f.). Cf Z. 1028» a1 n.
24. dxlyntov kat Ka8 abTd Kal KaTa cupPeRnKds = ore Ka’ adTd ovTE Kata ovpBeBnkds KwyTor.
29. Thy Tod Tavtés Thy GmAHv popdy, the diurnal apparent motion of the whole heavens.
32. ev Tots puoikois, Phys. viii. 8, 9, De Caclo i. 2, ii. 3-8. ;
33. bw dxwhtou te KiveioOar Kab aitiv Kal didiou odctas. These moving causes of the several planetary motions are, says Alexander (706. 32), not identical with the souls of the planets which Aristotle’s language in De Caelo 292% 20 ff. implies. It is in virtue of their souls that the planets are able to move at all, but it is in virtue of the desire of their moving causes for God that they move eternally and uniformly. The souls of the planets, we may add, are immanent in them, but the moving causes transcend them as God transcends the arAavijs odaipa. But it must be remembered that Aristotle nowhere speaks explicitly of souls of the planets, though he ascribes to the planets action and life (De Caelo 292% 20).
DY. 81d Thy eipnuevny aitiay mpdtepov seems to refer to ® 5-11.
6. ai 8 Gar wept odSepras odctas, cf. M. 2, 3.
17—1074* 14. The views of Eudoxus, Callippus, and Aristotle about the planetary system are discussed more fully by Simplicius (Comm,
in De Caelo 488. 18-24, 493. 4—506. 18), Eudoxus’ theory was first satisfactorily interpreted by Schiaparelli in Puddlicaziont del R. Osservatorio di Brera in Milano, 1875). Excellent accounts of the theory are given in Dreyer, Plane/ary Systems, 84-114, and in Heath, Arzstarchus of Samos, 190-224. The importance of the theory in the history of astronomy is well indicated in the following remarks by Dreyer(p. 107). ‘Scientific astronomy may really be said to date from Eudoxus and Kalippus, as we here for the first time meet that mutual influence of theory and observation on each other which characterizes the development of astronomy from century to century. Eudoxus is the first to go beyond mere philosophical reasoning about the construction of the universe ; he is the first to attempt systemati- cally to account for the planetary motions. When he has done this the next questionis how far this theory satisfies the observed phenomena, and Kalippus at once supplies the observational facts required to test the theory and modifies the latter until the theoretical and observed motions agree within the limit of accuracy attainable at the time. Philosophical speculation unsupported by steadily pursued observations is from henceforth abandoned ; the science of astronomy has started on its career.’
Simplicius derives his account largely from Sosigenes the Peripa- tetic (second century a.p., the teacher of Alexander Aphrodisiensis), who in turn borrowed from Eudemus’ treatment of the subject in his History of Astronomy. Simplicius quotes from Sosigenes the state- ment that Aristotle discussed in his Physzcal Problems objections to the hypotheses of astronomers (sc, Eudoxus and Callippus) arising from the fact that even the sizes of the planets do not appear always the same. Simplicius further refers to 1073 10-13 and 1074 14-17 as indicating dissatisfaction with the theory of concentric spheres, But Aristotle’s doubts are clearly only on points of detail.
‘The theory of concentric spheres was pursued for some time after Aristotle. Schiaparelli conjectures that even Archimedes still held to it. Autolycus, the author of the treatises Ox the moving sphere and On risings and settings, who lived till the end of the fourth or the begin- ning of the third century B.c., is said to have been the first to try, presumably by some modification of the theory, to meet the difficulties which had been seen from the first and were doubtless pointed out with greater insistence as time went on. What was ultimately fatal to it was of course the impossibility of reconciling the assumption of the invariability of the distance of each planet with the observed differences in the brightness, especially of Mars and Venus, at different times, and the apparent difference in the relative sizes of the sun and moon’ (Heath, 221).