Simplicius, On Aristotle’s On the Heavens 2.1-9. The Ancient Commentators on Aristotle

The unity of Aristotle’s De caelo has always posed a problem for commentators. After some preliminary remarks on bodies as the principal subject of natural philosophy, the Stagirite sets out, in Book 1, Chapters 2-4, his case for thinking that there is a fifth element or ‘aether’, a non-perishable body moving naturally in a circle, of which the heavenly spheres, the seven planets, and the fixed stars consist. The rest of Book 1 treats of the universe as a whole, arguing that it is spatially finite, unique, and eternal. In Book 2, Aristotle mainly deals with the shape and motion of the spheres, planets, and stars, before turning his attention to the earth in the last two chapters. Book 3 begins a study of the four sublunary elements that is only completed in De generatione et corruptione, and Book 4 is a monograph on weight and lightness.

Is there a heavenly thread running through all the diverse themes discussed by Aristotle in this work? The question as to what its subject really is has been answered differently by different commentators. Alexander of Aphrodisias was of the opinion that De caelo is about the cosmos (one of the three senses of ‘heaven’ recognised by Aristotle in Cael. 1.9), and thus also about the five elements of which the cosmos is composed. Iamblichus thought it deals primarily with the aether, although the cosmos as a whole and the other elements are also studied, since they are encompassed by and dependent on the aether. Simplicius, to whom we owe the reports of the earlier commentators’ views, himself held that this work — following after the Physics in the corpus aristotelicum — is in fact concerned with all five elements, being directly constructed from the first principles of natural bodies, and of these the aether is the first and most precious.¹

Simplicius’ commentary on Books 1 and 2 of De caelo have recently been translated for the Ancient Commentators on Aristotle series under the general editorship of Richard Sorabji. The commentary on Book 1 has been done by R. J. Hankinson. The first of three instalments appeared in 2002; it was provided with a brief preface by Sorabji as well as a useful 14-page introduction to Simplicius and his work by Hankinson. A second instalment appeared in 2004.

The volume under consideration here is the first of two instalments of Ian Mueller’s translation of the commentary on Book 2. Like Hankinson’s 2002 volume, it includes notes to the translation, a bibliography, a section on textual questions, an English-Greek glossary, a Greek-English index, and a subject index; in addition there are indexes of passages and names. A brief introduction deals with the textual basis and some ‘issues of translation’. But no attempt is made to put the translated work into its historical and philosophical context. Perhaps the reader is expected to turn to Hankinson’s 2002 volume for such information; in that case, it is remarkable that this volume is never mentioned by Mueller, nor is it found in his bibliography.

Apart from Themistius’ paraphrase, preserved in a Hebrew translation, Simplicius’ commentary is the only surviving ancient commentary on De caelo. Thanks to Simplicius’ habit of quoting and reporting earlier and contemporary philosophers’ views at length, it is also an important source for ancient cosmology in general. Special attention has been paid in recent years to Simplicius’ polemic against Philoponus over the Aristotelian doctrine of the eternity of the world, which Philoponus as a Christian rejected. This polemic is found in the commentary on Book 1; it incorporates long stretches of a lost work by Philoponus, which have earlier been collected and translated by Christian Wildberg for another volume in the same series.² They are thus omitted from Hankinson’s translation, as are Simplicius’ replies to Philoponus, due to appear in yet another volume translated by Mueller.

Book 2 does not deal with questions of such fundamental importance as Book 1, and so Simplicius’ commentary on it may be expected to contain less material of interest. Still, there are many passages here that deserve attention. Not least among these are the many quotations, reports, and discussions of passages of Alexander’s lost commentary.³ Simplicius held Alexander in esteem as an Aristotelian scholar, and he frequently adopted his suggestions of interpretation, sometimes tacitly (as can be ascertained with the help of Themistius’ paraphrase).⁴ But he frowned upon him as a critic of Plato, and he made it his duty to show how Alexander systematically exaggerated the differences between Aristotle’s doctrines and Plato’s. An important part of this task was to demonstrate that the Aristotelian text could — indeed should — be interpreted in a way which did not imply criticism of Plato’s views.

One example of how Simplicius performed this task is his attempt to show that Aristotle’s denial (in Cael. 2.8) that the ‘stars’ (including the planets) move independently of the spheres to which they are attached does not contradict Plato’s view (in Timaeus 40a-b) that the fixed stars are simultaneously rotating and moving forward. This attempt may or may not have been prompted by Alexander’s commentary: Simplicius only refers to his opponents as ‘those who strive contentiously to put Aristotle in a different camp from Plato’ (454.23-24, trans. Mueller). It involves taking Aristotelian passages (notably 290a13-14) to mean the opposite of what they say, and ends in the rather implausible conclusion that Aristotle only wished to deny that the stars move forward by rotating or rolling, not the very fact that they rotate (455.24-25). (See also my comment on Mueller’s translation of this passage at the end of this review.)

But the most illustrative example in this part of the commentary is Simplicius’ discussion of Cael. 2.1, 284a27-35. This has to do with the souls of the heavenly bodies. The discovery that the heavenly bodies consist of a substance that moves naturally in a circle led Aristotle to conclude that the heavenly bodies — in contrast to sublunary animals — do not have souls which counteract the natural motion of the elements of which they are composed. This is not to say that the heavenly bodies do not have souls — Aristotle repeatedly asserts that they do — only that these souls do not use force to make the bodies move against their nature. Thus Aristotle is in a position to criticise, in our passage, the idea that the heaven’s eternal subsistence is due to the constraint of a soul as being unreasonable. It is unreasonable, he says, because it burdens the heavenly soul with eternal and unceasing labour; and he compares its fate to that of Ixion, who was punished by Zeus for trying to seduce Hera, by being bound to a wheel , ‘on which he is whirled by winds through the air’, as Pseudo-Apollodorus relates (E 1.20, trans. Frazer).

Simplicius agrees with Alexander that what Aristotle has in mind here is the description of the world soul in Plato’s Timaeus. But he scolds him for thinking that the target of Aristotle’s criticism is not an erroneous interpretation of this description, but Plato’s actual view. According to Alexander, any soul that moves a body composed of one or more of the four elements (as the heavens are in the Timaeus) in a circle must use force to make that body move against its nature. Alexander also makes an addition to Aristotle’s criticism, which seems to exasperate Simplicius: since (according to Plato) it is better for the soul to be separated from the body, Plato’s world soul is in a worse condition than the souls of mortal creatures, for it will never be separated from its body (376.34-377.2; 377.34-378.10).

Simplicius solemnly undertakes to scrutinise Alexander’s account for the benefit of more superficial readers, who might otherwise be influenced to a hostile view of Plato’s doctrines. It is hard to see that he lives up to his promise. He does produce a couple of objections to Alexander’s added criticism, but they seem singularly irrelevant, since they completely disregard its dialectical character. First, he asks, if being separated from the body is better for the soul, in what way will the divine souls achieve what is better for them according to Alexander? Second, if Alexander thinks that the souls of mortal bodies are inseparable actualities (and thus will be destroyed with the body), how can he maintain that they have a better lot than the souls of immortal bodies (which are, after all, immortal)? (377.29-34; 378.22-29)

Simplicius concludes that Aristotle does not in 284a27-35 take Plato to task for having a soul move the heavens, nor even for having a soul move the heavens against their nature; on the contrary, he wants to prevent the misconstruction of Plato’s description in the Timaeus as referring to some kind of corporeal and coercive causing of motion, like pushing. Plato, Simplicius avers, did conceive of the motion of the heavens as natural to them, notwithstanding the fact that they are composed of the highest states of the four elements. Obviously, Aristotle, who had written a summary of the Timaeus, knew this (378.29-379.17).

But according to Simplicius, Alexander has misunderstood not only Plato’s but also Aristotle’s view on the heavenly soul. Alexander’s understanding of the latter is that the heavenly soul is identical with the nature of the heavenly body, that is, with the potency of the heavenly body to move in a circle; but since the heavenly body is finite it cannot possess an infinite potency, and consequently the heavenly soul cannot cause the eternity of the motion; for this the first mover is responsible. Simplicius grants the last point to Alexander, but repudiates his identification of the heavenly body’s soul with its nature. Simplicius’ own view of the matter — which he also ascribes to Plato and Aristotle — is that nature and soul here as everywhere else are distinct entities: nature is a propensity for being moved, but it cannot be the cause of motion; this must be a soul (379.32-380.19; 381.19-382.19).

I have dwelt on this section of the commentary partly because it is one of the most interesting. The interpretations of 284a27-35 by Alexander and Simplicius respectively prefigure the positions of 20th-century commentators on Aristotle’s view of the heavenly souls: W. K. C. Guthrie compared (following a lead from Philip Merlan) Sir David Ross’ view to that of Simplicius, and his own to that of Alexander.⁵ But partly also because it seems to be one of the most problematic parts of Mueller’s translation. Mueller betrays some uncertainty as to the main point of the section, when he says in a note to 379.16 (p. 132 n. 73) that apparently ‘Simplicius does not think Aristotle is attacking Plato here, but he does not tell us whom Aristotle is talking about’. It seems clear enough to me that Simplicius thinks Aristotle is talking about Plato (that’s what he says at 376.34-377.2), but not attacking his views, only a possible misconstruction of them. However, there are a number of errors and infelicities in Mueller’s translation which I think may make it difficult for the reader to perceive this clearly. A list of some of the more serious mistakes in the translation of this and other sections will be found at the end of this review.

The basis of Mueller’s translation is J. L. Heiberg’s edition in Commentaria in Aristotelem Graeca (vol. 7; Berlin, 1894). Mueller rightly points out the unreliability of Heiberg’s text, stemming primarily from a rather arbitrary use of the MS witnesses (pp. 1-3). It is, however, not correct, as Mueller says (p. 2), that Heiberg judged the MS F to be a descendant of A. (It would have been surprising if he did, since he often prefers F’s readings to those of A.) In fact he judged it to be a descendant of A’s exemplar (p. vii). Of course, this is all the more reason to agree with Mueller that Heiberg ought to have made a full collation of F and to have recorded all its (non-adopted) variants in the apparatus.

Mueller lists some 60 passages where he has chosen to translate another text than the one printed by Heiberg; most of these emendations (or ‘textual suggestions’ as Mueller prefers to call them) are fairly trivial; many of them are supported by F and quite likely to be successful. There are also a couple of good conjectures, such as ἀεὶ κινητὸν (or, better still, ἀεικίνητον) in 400.6.⁶And some less convincing suggestions, for example the following:

In 385.34 and 36, the change of τρίτον into πέμπτον twice in three lines without any MS support is not only very bold, but also unnecessary, since the objection that follows in the text (386.1-23) indeed seems to be the third one, after (1) ‘although there are six distinctions, they [sc. the Pythagoreans] used only two’ (384.23-25) and (2) ‘they have left out the more important distinctions, up and down’ (384.25-385.29, subdivided into four at 384.27; 385.4; 385.7; 385.23, and summarised at 385.29-31).

In 377.11-12, I would suggest σύμφυρσιν for Heiberg’s συρφετὴν, based on A’s σύρφυσιν and F’s σύμμικτον φύσιν (preferred by Mueller). Cf. 428.21; also, 381.11. (This also makes it necessary to read ἐνεργειῶν in 377.12 with Karsten and Mueller.)

In 380.35, Mueller adopts F’s (and Karsten’s) reading τῆς ψυχῆς, and translates the whole passage thus: ‘so too the nature of the divine body would reasonably appear also to be the power of its soul’. This is militated against by 380.15 and 381.12-13: Alexander identifies not only the divine body’s nature with its soul but also its nature with its potency and its potency with its soul. I think the text is better left to stand. It may be translated: ‘so too the divine body’s nature as well as its potency would reasonably appear to be its soul’.⁷

In 441.3, it is true that σωματικὰς seems to require emendation, but ἀσωματικάς is not, I think, a Greek word (although a TLG search returned one hit: Damascius, In Parm. 213.28). ἀσώματους would be better.

In 459.3, it is clear that the text translated by Mueller is what Simplicius ought to have written, but not that it is what he actually wrote.

In 469.7-8, it is not advisable to change the accusatives in the MSS’ reading τὸ αὐγοειδὲς αὐτοῦ καὶ οὐράνιον ὄχημα into genitives. The first part of this sentence may be translated: ‘But if someone, despite carrying this mortal body ( καὶ τοῦτο τὸ σῶμα τὸ ἐπίκηρον ἐξηρτημένος), had his luminous and heavenly vehicle and the senses in it purified . . .’.

For the most part, Mueller’s translation successfully combines a high degree of formal equivalence with reasonable readability. A glance at the English-Greek Glossary and the Greek-English Index reveals that to one word type in the original usually corresponds one word type in the translation, and vice versa. In the same way, one-to-one correspondence has clearly been a guiding principle on the word token level. I have only observed two non-trivial systematic deviations from the formal equivalence model: one is a rather wide latitude in rendering the moods and tenses of the Greek verbs, which sometimes (especially in conditional sentences) results in slight distortions of the sense; another is that long and complicated periods are often (though not always) divided into two or more independent sentences. While this is mostly beneficial, it occasionally obscures the structure of Simplicius’ arguments (as e.g. in 449.21-29, or in the elaborate summary of Book 1 in 365.2-18). It should also be said that Mueller supplements the missing parts of the Aristotelian lemmata, and thus in effect also offers a new translation of De caelo 2.1-9.

The notes are mostly helpful, supplying references as well as comments on the text and on the arguments. (In a few cases they simply consist of the last translated Greek word in transliteration; this could have been supplied within brackets in the translation, or dispensed with altogether, since there is an English-Greek glossary.) In one case, I think some clarification is needed. In n. 298 (p. 145), Mueller says that what Simplicius in 422.11 calls each heavenly sphere’s own motion, as opposed to the motion imposed on it by the sphere of the fixed stars, is ‘rotation on their axes’, and refers to the commentary on Chapters 8 and 9. That the motion is rotatory is understood: this is the only natural motion for the heavenly spheres; but what Simplicius has in mind here is of course the rotation from west to east of the seven planet-spheres. This has nothing to do with the planets’ rotation on their axes (discussed in the commentary on Chapters 8 and 9), which is imperceptible for us and thus cannot account for any apparent non-uniformity.

The design and layout of the book are much the same as in the rest of the series, with much the same advantages and disadvantages (examples of the latter are transliterated Greek and notes inconveniently placed at the end). There are a few typos, especially in the transliterated Greek.

These criticisms apart, there is no doubt that Mueller’s translation and notes will contribute to a wider knowledge and deeper understanding of Simplicius’ work, as well as of ancient cosmology at large. It should be on the shelves of every library with a serious interest in ancient philosophy and science.

Lastly, I have assembled a few passages where I think Mueller’s translation is not conducive to a proper understanding of the text.

377.29-33: The passage may be translated ‘Well then, since even in this matter I give precedence to the truth, which is dear to god and to Aristotle (allusion to Aristotle’s famous dictum in Eth. Nic. 6.1, 1096a11-17?), I will add the things that Alexander as the opinions of Plato and try to investigate them carefully, for the benefit of those who read his [sc. Alexander’s] arguments more superficially and might be influenced by them to a hostile view of Plato’s doctrines . . .’.

378.27: The subject of λέγοντα is Plato, not Alexander.

378.35: The subject of ηὐλαβήθη is Aristotle, not Plato. Aristotle, Simplicius says, took care that Plato’s idea would not be misunderstood by readers unfamiliar with his way of expression.

379.1: The subject of παρήγαγεν is Aristotle, not Plato. The word means ‘brought in, introduced’, not ‘avoids’. Aristotle, Simplicius says, brought in Ixion in order to condemn an interpretation of Plato that he realised was possible but knew was wrong.

380.14-15: οὐχ οἷόν τε ταύτην τοῦ εἰς ἄπειρον κινεῖν εἶναι δύναμίν γε οὖσαν τοῦ πεπερασμένου. A predicate noun seems to be missing here, but if we add αἰτίαν with Karsten, I think we must also change κινεῖν into κινεῖσθαι. An alternative solution might be to read τὸ εἰς ἄπειρον κινοῦν instead of TOU= EI)S A)/PEIRON κινεῖν. In any case, the meaning seems to be ‘it is impossible for this soul to be that which causes motion ad infinitum, since it is a power of something finite’, rather than ‘since it is a finite thing, this could not be a power of causing motion to infinity’.

381.17-18: αὕτη γάρ ἐστιν ἡ πρακτική should probably be rendered ‘for the active life is life involving soul’, rather than ‘for the life requiring soul is the practical life’. The purpose of the sentence is to justify the glossing of Aristotle’s ‘life’ as ‘life involving soul’ in the preceding sentence.

381.24-25: The context seems to require that πτώσει μᾶλλον ἔοικεν ἢ ὁλκῇ τινι means ‘rather resembles falling or a kind of pulling’, not ‘resembles falling rather than a kind of pulling’.

381.21-35: In this discussion Mueller translates ὅλον alternately as ‘universe’ and as ‘whole’ (viz. of one or other of the four elements). Thus we read, e.g. ‘[P]arts which are torn asunder from their wholes [ τῶν ὅλων ] are deprived of their source of life in the universe [ ἐν τῳ ] and their complete nature, but they are said to have a nature insofar as when they move they are such as to be again in contact with the universe [ τῳ ]’ (381.28-31). I think it would have been better to stick to ‘whole’, in order not to rule out the possibility that TO ὅλον in all or some of these instances refers to the entirety of each single element, rather than the entirety of all things (cf. Arist., Phys. 4.5, 212b29-32). Cf. also 372.20; 423.13. Certainly, THN E)PI TO ὅλον R(OPHN in 381.23 must be the inclination ‘towards the whole [of the element in question]’, rather than ‘in relation to the entirety [of the universe]’.

381.35: ταῦτα, οἶμαι, καὶ τῳ cannot mean ‘I believe these things, and I say that Aristotle does too’, but rather ‘I venture to say that these are also Aristotle’s views’.

382.12: The subject of ἐχούσης is the motion, not the heaven.

382.17: διὰ τῆς φύσεως ἐνδιδομένη means ‘which is transmitted through nature’, rather than ‘which is given by nature’. Cf. 381.32; 381.34; 382.10.

385.35-36: The conditional clause may be translated ‘if one takes all the first objections as one, saying that it has been established through them that the most important things have been passed over’, rather than ‘if one takes all of the first things as one argument saying that they have passed over the more important things’. See also the remark above on Mueller’s textual suggestion here.

388.1: αἱ δυνάμεις αὗται means ‘these powers’, not ‘the powers themselves’.

389.34-35: The punctuation of Cael. 2.2, 285b4 suggested by Simplicius can hardly be, as Mueller translates, ‘a comma before “but would seem not to . . .” ‘, since there is no risk that any amphiboly will arise from reading the two sentences together. What Simplicius suggests must be a comma (strictly, a hypostigme) after‘but would seem not to’ ( δόξει δὲ οὔ), to separate the negation from the following prepositional phrase, as in Moraux’s edition.

In 394.20, ἐπεὶ introduces not the reason for the fact expressed in the preceding clause, but the reason for thinking that it is a fact. Thus the passage may be translated ‘He says that their motions are “opposite” in the sense of “reverse”. For he has proved previously . . . that there is no motion opposite to motion in a circle’. Mueller’s translation is: ‘He says that their motions are “opposite” instead of “reverse” since he has proved previously . . . that there is no motion opposite to motion in a circle’. 395.8; 13: I find ‘spatial determinants’ odd for κατὰ τόπον ὡρισμένα. Up and down etc. are defined by place, they do not determine space.

397.25: οὐδὲ ἔξωθεν τὸ ὅλον ἔχουσιν must mean ‘they also do not have it [sc. τὸ λογικὸν καὶ νοερὸν, l. 24] from outside at all’, rather than ‘they do not possess anything outside of their wholeness’.

401.1: τῆς Ἀριστοτέλους ἑρμενευτικῆς ἀκριβείας means ‘Aristotle’s accuracy of expression’, rather than ‘the accurate interpretation of Aristotle’. The whole sentence (400.34-401.2) may be translated: ‘And in truth, if he [sc. Aristotle] had compared two of the elements with the other two, I don’t think it would have been in keeping with Aristotle’s accuracy of expression to say — not “either relative to either” but — “each relative to each”.’

403.6: καὶ διὰ τοῦτο καὶ ἐκεῖνα συνεισάγον means ‘and that is why it [sc. fire] also entails them [sc. air and water]’, rather than ‘and that is why he also introduced them’.

403.19-21: The meaning of the sentence must be ‘And this method — derived from motion — of demonstrating that there is an eternal body was appropriate for discussions of motion’, rather than ‘And this would be the method of demonstrating that there is an eternal body based on motion and taken in a way appropriate for discussions of motion’.

403.36; 404.1; 404.3: τεκμήριον is here translated as ‘ evidence’. I think the supplemented word is misleading: Simplicius’ point seems to be simply that the deduction is not demonstrative, since the premisses are not explanatory of the conclusion.

404.20-21 (and cf. 405.19-20): οὐ γὰρ συνυπάρχειν ἀναγκαῖον τὰ ἐναντία ὥσπερ τὰ πρός τι means ‘it is not necessary that opposites exist together, as is the case with relatives’, rather than ‘it is necessary that opposites not exist together in the same thing in the way that relatives can’. For the principle, see 396.2-3.

409.33 οὐχ ἁπλῶς ὑγιὴς means ‘not unqualifiedly sound’, rather than ‘not completely sound’.

410.25-29: The sentence may be translated ‘But the astronomers prove on the basis of the appearances that the heaven cannot have any other shape than that of the sphere, even conceding that some figures, e.g. the cylinder, the cone, the lentil-shaped, the egg-shaped and the solid called rhomboidal, have their poles in such a way as always to occupy the same place’. That is to say, the loophole left by Aristotle is closed by Ptolemy (or, rather, Theon: see Mueller’s note 238 on p.141).

412.21-23: The sentence means ‘Therefore, it is necessary that what moves with the fastest and least movement, i.e. the circular one, is circular if two-dimensional, and spherical if three-dimensional’, rather than ‘Therefore, it is necessary that the fastest and least motion is circular in the case of plane figures and spherical in the case of solids’. This may go some way towards clarifying the obscurities signalled by Mueller (p. 142 n. 251).

413.21: εἰς τὸ κενὸν ἀπάγουσα means ‘which led to the [absurd conclusion that there is] void’, rather than ‘which invoked a void’.

414.16: κἂν ἐνδεικνύηταί τι καὶ ἄλλο means ‘even if Plato also hints at something else’ rather than ‘even if Plato indicates something else’. That is to say, Simplicius does not reject Aristotle’s interpretation of Tim. 33b.

416.22-25: ἐπί with the accusative means ‘to’, not ‘in the case of’. Thus, α in l. 22 must be deleted with Karsten, and the text will mean: ‘So if there be drawn, to the points E and C or to any other limits of the equal straight lines from the point A that are found between them, the straight lines from A in a plane, then the line which is joined at the limits of the straight lines will be circular . . .’.

416.31: συρρεῖ should be translated ‘flow together’ rather than ‘flow’.

419.26-27: The sentence means ‘For in addition to moving with a simple and unceasing movement, also moving towards what is more honourable, i.e. the front, is better’, rather than ‘For moving towards what is more honourable, i.e. the front, is better for moving simply and unceasingly’.

420.35-421.6: to the protases in 420.35-37 corresponds the apodosis in 421.2-3. Mueller’s translation is anacoluthic: it has the protases but not the apodosis.

421.27-28: The passage means ‘So, since, if the motion came to be in the other direction, it was necessary that the activities and powers of things in the heaven also be different . . .’, rather than ‘So, since, if the motions and activities of things in the heaven came to be in the other direction, it would be necessary that their powers also be different . . .’

421.31-32: καίτοι ὡς ἀδιάφορον ὂν οὕτως ἢ ἐκείνως ἡ ἀπορία ἐγίνετο probably means ‘But the difficulty arose from the assumption that it was indifferent whether it was ordered this way or that’, rather than ‘There is then no difference between putting the difficulty this way and putting it that way’.

423.24ff. εἰς τὸ πλάγιον means ‘horizontally’, not ‘sideways’. Neither spears nor the majority of animals normally move sideways.

425.1: The words οὔτε ἀκμὴν (‘neither a maximum speed . . .’) are not translated by Mueller.

425.26: βουλόμενος αὐτῷ καὶ τὰ φαινόμενα μαρτυρεῖν probably means ‘and wanted the phenomena to bear witness for it, too’ (Aristotle wanted the phenomena to confirm his account of the heaven), rather than ‘and wished to bear witness for the way it appears’.

429.12-16: The argument turns on the passive perfect participles, and is difficult to render in English without extensive paraphrasing. I would suggest something along these lines: ‘It is perhaps also possible to say that, in the case of things in which deceleration comes after the maximum speed, it is called deceleration in relation to the maximum speed resulting from acceleration, and in the case of things in which the acceleration is before the maximum speed, such as things moving naturally, that the motion which proceeds to a maximum speed is said to accelerate in relation to the original condition resulting from deceleration’.

431.15-16: ὡς ἄπειροι πάντως ἐσόμεναι ἥ τε ἄνεσις καὶ ἡ ἐπίτασις ὑπὸ τοῦ Ἀριστοτέλους ἐλέγχονται seems to mean ‘any prospect whatsoever of infinite acceleration and deceleration is refuted by Aristotle’, rather than ‘what is refuted by Aristotle is only the idea that both the acceleration and the deceleration might be absolutely infinite’.

435.25: οὐράνιον πᾶν must mean ‘altogether heavenly’, rather than ‘everything heavenly’.

436.17: οἷς ἔστιν ἐναντία must mean ‘to which there are opposites’, rather than ‘to which they are opposite’.

436.25-29: The structure of the passage seems to be as follows: ‘Anyway, one may agree with Alexander that in the heavens these oppositions exist without the difficulties to which mortals are subject and affections which produce destruction. But it seems to me that there is reason to scrutinise the assertion that . . .’

436.31-33: εἰ δὲ in l. 32-33 corresponds to εἰ μὲν in l. 29. Thus one should understand τοῦτο λέγει. The whole passage may be translated ‘For nor does any other thing change while remaining just what it is, but rather the substratum is said to change when it takes on ever new differentiae. But if what he says is that it doesn’t change at all because of the opposition, how can the argument be true?’

436.36-437.1: ἤδη μὲν μεταβάλλον means ‘is already changing’, not ‘has already changed’.

In 437.3-6, I think a more literal translation would also be more readily comprehensible: ‘and one part of it becomes air when heated, and the white departs with this, while another part becomes water when liquefied. And if heat were not the opposite of coldness, and liquefaction and division the opposites of coagulation and aggregation, snow would never be dissolved’.

438.2-4: ἦν γὰρ ἂν introduces the (unreal) consequent in the first part of a reductio ad impossibile. The sentence may be translated: ‘For then [sc. if there had been a thing opposite to the heavenly body] there would also have been a motion opposite to its present motion, and that thing, from which and into which would have changed, would have moved naturally with this motion’. (But such a motion is impossible, and therefore there is no such thing.)

439.1: φασίν means ‘they say’, not ‘he asks’.

439.9-10: τὰς μολιβδίδας τὰς τὸν σίδηρον ἐν τῳ means ‘lead solder which joins the iron with the wood ‘, rather than ‘lead balls which contain iron inside wood’.

440.6-11: The passage may be translated ‘it is not unreasonable that around a certain part of the body revolving as a unit [sc. the sun-sphere], namely the part where there is a large and compressed and not very distant body in it [sc. the sun], the heat from the motion in the underlying body [sc. the air] becomes greater and more intense, since the contact in connection with the motion will involve more resistance around this part, because of the denseness and the size of the body’.

444.12-13: κἂν μὴ γενέσεως αὐτοῖς καὶ φθορᾶς, ἀλλὰ πάντως ἀλλοιώσεως αἰτίας γίνεσθαι παθητικῆς means ‘they become causes, if not of their coming-to-be and destruction, at any rate of their passive alteration’, rather than ‘even if they do not come to be and are not destroyed, there are always causes of their passive alteration’.

455.24-25: ὥστε πανταχοῦ τὸ μὴ PROI+έναι δι’ ἑαυτῶν ἀναιρεῖ τὴν τοιαύτην κίνησιν, ἀλλ’ οὐχ ἁπλῶς τὸ κινεῖσθαι must mean ‘Thus he everywhere eliminates progressing on one’s own with this kind of motion, but not simply moving [with this kind of motion]’, rather than ‘Thus he eliminates not progressing on one’s own, but not motion in general’.

470.20: μήτε διὰ σωμάτων ψοφητικῶν means ‘nor through bodies which make a sound’, rather than ‘or because of bodies which make a sound’.

Notes

1. Simplicius, In Cael. 1.2-5.34.

2. Philoponus, Against Aristotle on the Eternity of the World. Translated by C. Wildberg. London, 1987.

3. The fragments of Alexander’s commentary are currently being edited by Andrea Rescigno: see Robert B. Todd’s review in BMCR 2005.10.38.

4. See Paul Moraux, Der Aristotelismus bei den Griechen, vol. 3, Alexander von Aphrodisias (Berlin and New York, 2001), pp. 185-88.

5. Aristotle, On the Heavens (Cambridge, Mass., 1945), pp. xxxi-xxxii, n.

6. An editor for BMCR has proposed that Moerbeke’s Latin rendering “facilis mobile” suggests instead the emendation EUKINHTON.

7. In 380.36, Moraux (op. cit., p. 176 n. 217) suggested that φύσεως should be corrected into φύσις, following Simplicius, In Phys. 1219.6.