In these last words Buttmann has exactly distinguished the true, constant, and essential meaning of the word, from the casual accessories which become conjoined with it by the special circumstances of some peculiar cases. The constant and true meaning of the word is, being packed or fastened close round, squeezing or grasping around. The idea of rotating or revolving is quite foreign to this meaning, but may nevertheless become conjoined with it, in certain particular cases, by accidental circumstances.
Let us illustrate this. When I say that a body A is εἱλόμενον or ἰλλόμενον (packed or fastened close round, squeezing or grasping around), another body B, I affirm nothing about revolution or rotation. This is an idea foreign to the proposition per se, yet capable of being annexed or implicated with it under some accidental circumstances. Whether in any particular case it be so implicated or not depends on the question “What is the nature of the body B, round which I affirm A to be fastened?” 1. It may be an oak tree or a pillar, firmly planted and stationary. 2. It may be some other body, moving, but moving in a rectilinear direction. 3. Lastly, it may be a body rotating or intended to rotate, like a spindle, a spit, or the rolling cylinder of a machine. In the first supposition, all motion is excluded: in the second, rectilinear motion is implied, but rotatory motion is excluded: in the third, rotatory motion is implied as a certain adjunct. The body which is fastened round another, must share the motion or the rest of that other. If the body B is a revolving cylinder, and if I affirm that A is packed or fastened close round it, I introduce the idea of rotation; though only as an accessory and implied fact, in addition to that which the proposition affirms. The body A, being fastened round the cylinder B, must either revolve along with it and round it, or it must arrest the rotation of B. If the one revolves, so must the other; both must either revolve together, or stand still together. This is a new fact, distinct from what is affirmed in the proposition, yet implied in it or capable of being inferred from it through induction and experience.
Here we see exactly the position of Plato in regard to the rotation of the earth. He does not affirm it in express terms, but he affirms what implies it. For when he says that the earth is packed, or fastened close round the cosmical axis, he conveys to us by implication the knowledge of another and distinct fact — that the earth and the cosmical axis must either revolve together or remain stationary together — that the earth must either revolve along with the axis or arrest the revolutions of the axis. It is manifest that Plato does not mean the revolutions of the axis of the kosmos to be arrested: they are absolutely essential to the scheme of the Timæus — they are the grand motive-agency of the kosmos. He must, therefore, mean to imply that the earth revolves along with and around the cosmical axis. And thus the word εἱλόμενον or ἰλλόμενον, according to Buttmann’s doctrine, becomes accidentally conjoined, through the specialities of this case, with an accessory idea of rotation or revolution; though that idea is foreign to its constant and natural meaning.
Now if we turn to Aristotle, we shall find that he understood the word εἱλόμενον or ἰλλόμενον, and the proposition of Plato, exactly in this sense. Here I am compelled to depart from Buttmann, who affirms (p. 152), with an expression of astonishment, that Aristotle misunderstood the proposition of Plato, and interpreted εἱλόμενον or ἰλλόμενον as if it meant directly as well as incontestably, rotating or revolving. Proklus, in his Commentary on the Timæus, had before raised the same controversy with Aristotle — ἰλλομένην δὲ, τὴν σφιγγομένην δηλοῖ καὶ συνεχομένην οὐ γὰρ ὡς Ἀριστοτέλης οἴεται, τὴν κινουμένην (Procl. p. 681). Let us, therefore, examine the passages of Aristotle out of which this difficulty arises.
The passages are two, both of them in the second book De Cœlo; one in cap. 13, the other in cap. 14 (p. 293 b. 30, 296 a. 25).
1. The first stands — ἔνιοι δὲ καὶ κειμένην (τὴν γῆν) ἐπὶ τοῦ κέντρου φασὶν αὐτὴν ἴλλεσθαι περὶ τὸν διὰ παντὸς τεταμένον πόλον, ὥσπερ ἐν τῷ Τιμαίῳ γέγραπται. Such is the reading of Bekker in the Berlin edition: but he gives various readings of two different MSS. — the one having ἴλλεσθαι καὶ κινεῖσθαι — the other εἱλεῖσθαι καὶ κινεῖσθαι.
2. The second stands, beginning chap. 14 — ἡμεῖς δὲ λέγωμεν πρῶτον πότερον (the earth) ἔχει κίνησιν ἢ μένει· καθάπερ γὰρ εἴπομεν, οἱ μὲν αὐτὴν ἓν τῶν ἄστρων ποιοῦσιν, οἱ δ’ ἐπὶ τοῦ μέσου θέντες ἴλλεσθαι καὶ κινεῖσhαί φασι περὶ τὸν πόλον μέσον.
Now, in the first of these two passages, where Aristotle simply brings the doctrine to view without any comment, he expressly refers to the Timæus, and therefore quotes the expression of that dialogue without any enlargement. He undoubtedly understands the affirmation of Plato — that the earth was fastened round the cosmical axis — as implying that it rotated along with the rotations of that axis. Aristotle thus construes ἴλλεσθαι, in that particular proposition of the Timæus, as implying rotation. But he plainly did not construe ἴλλεσθαι as naturally and constantly either denoting or implying rotation. This is proved by his language in the second passage, where he reproduces the very same doctrine with a view to discuss and confute it, and without special reference to the Platonic Timæus. Here we find that he is not satisfied to express the doctrine by the single word ἴλλεσθαι. He subjoins another verb — ἴλλεσθαι καὶ κινεῖσθαι: thus bringing into explicit enunciation the fact of rotatory movement, which, while ἴλλεσθαι stood alone, was only known by implication and inference from the circumstances of the particular case. If he had supposed ἴλλεσθαι by itself to signify revolving the addition of κινεῖσθαι would have been useless, unmeaning, and even impertinent. Aristotle, as Boeckh remarks, is not given to multiply words unnecessarily.
It thus appears, when we examine the passages of Aristotle, that he understood ἴλλεσθαι quite in conformity with Buttmann’s explanation. Rotatory movement forms no part of the meaning of the word; yet it may accidentally, in a particular case, be implied as an adjunct of the meaning, by virtue of the special circumstances of that case. Aristotle describes the doctrine as held by some persons. He doubtless has in view various Platonists of his time, who adopted and defended what had been originally advanced by Plato in the Timæus.
M. Boeckh, in a discussion of some length (Untersuch. p. 76-84), maintains the opinion that the reading in the first passage of Aristotle is incorrect; that the two words ἴλλεσθαι καὶ κινεῖσθαι ought to stand in the first as they do in the second, — as he thinks that they stood in the copy of Simplikius: that Aristotle only made reference to Plato with a view to the peculiar word ἴλλεσθαι, and not to the general doctrine of the rotation of the earth: that he comments upon this doctrine as held by others, but not by Plato — who (according to Boeckh) was known by everyone not to hold it. M. Boeckh gives this only as a conjecture, and I cannot regard his arguments in support of it as convincing. But even if he had convinced me that ἴλλεσθαι καὶ κινεῖσθαι were the true reading in the first passage, as well as in the second, I should merely say that Aristotle had not thought himself precluded by the reference to the Timæus from bringing out into explicit enunciation what the Platonists whom he had in view knew to be implied and intended by the passage. This indeed is a loose mode of citation, which I shall not ascribe to Aristotle without good evidence. In the present case such evidence appears to me wanting.[4]