§4Ἔστι δέ τις ἀπορία περὶ τὰς κινήσεις τῶν τοῦ οὐρανοῦ μορίων, 4 ἣν ὡς οὖσαν οἰκείαν τοῖς εἰρημένοις ἐπισκέψαιτʼ ἄν τις.
There is a certain puzzle concerning the movements of the parts of the heaven, 4 which one might examine as being appropriate to what has been said.
ἐὰν γάρ τις ὑπερβάλλῃ τῇ δυνάμει τῆς κινήσεως τὴν τῆς γῆς ἠρεμίαν, δῆλον ὅτι κινήσει αὐτὴν ἀπὸ τοῦ μέσου.
For if someone exceeds by the force of his movement the rest of the earth, it is clear that he will move it away from the center.
καὶ ἡ ἰσχὺς δʼ ἀφʼ ἧς αὕτη ἡ δύναμις, ὅτι οὐκ ἄπειρος, φανερόν· οὐδὲ γὰρ ἡ γῆ ἄπειρος, ὥστʼ οὐδὲ τὸ βάρος αὐτῆς.
And that the strength from which this power comes is not infinite is clear; for neither is the earth infinite, so that neither is its weight.
ἐπεὶ δὲ τὸ ἀδύνατον λέγεται πλεοναχῶς (οὐ γὰρ ὡσαύτως τήν τε φωνὴν ἀδύνατόν φαμεν εἶναι ὁραθῆναι καὶ τοὺς ἐπὶ τῆς σελήνης ὑφʼ ἡμῶν· τὸ μὲν γὰρ ἐξ ἀνάγκης, τὸ δὲ πεφυκὸς ὁρᾶσθαι οὐκ ὀφθήσεται), τὸν δʼ οὐρανὸν ἄφθαρτον εἶναι καὶ ἀδιάλυτον οἰόμεθα μὲν ἐξ ἀνάγκης, συμβαίνει δὲ κατὰ τοῦτον τὸν λόγον οὐκ ἐξ ἀνάγκης· (πέφυκε γὰρ καὶ ἐνδέχεται εἶναι κίνησιν μείζω καὶ ἀφʼ ἧς ἠρεμεῖ ἡ γῆ καὶ ἀφʼ ἧς κινοῦνται τὸ πῦρ καὶ τὸ ἄνω σῶμα)· εἰ μὲν οὖν εἰσὶν ὑπερέχουσαι κινήσεις, διαλυθήσεται ταῦτα ὑπʼ ἀλλήλων· εἰ δὲ μὴ εἰσὶ μέν, ἐνδέχεται δʼ εἶναι (ἄπειρον γὰρ οὐκ ἐνδέχεται διὰ τὸ μηδὲ σῶμα ἐνδέχεσθαι ἄπειρον εἶναι), ἐνδέχοιτʼ ἂν διαλυθῆναι τὸν οὐρανόν.
And since "impossible" is said in many ways (for we do not say in the same way that it is impossible for a voice to be seen as it is for those on the moon to be seen by us; for the former is of necessity, while the latter, though being of a nature to be seen, will not be seen), and we think on the one hand that the heaven is indestructible and indissoluble of necessity, but on the other hand it turns out according to this argument not to be of necessity (for it is of a nature and it is possible for there to be a movement greater than both that by which the earth is at rest and that by which fire and the upper body are moved); if, therefore, there are exceeding movements, these will be dissolved by one another; but if they do not indeed exist, but it is possible for them to exist (for an infinite movement is not possible because it is not even possible for a body to be infinite), it would be possible for the heaven to be dissolved.
τί γὰρ κωλύει τοῦτο συμβῆναι, εἴπερ μὴ ἀδύνατον;
For what prevents this from happening, if indeed it is not impossible?
οὐκ ἀδύνατον δέ, εἰ μὴ τἀντικείμενον ἀναγκαῖον.
And it is not impossible, unless the opposite is necessary.
ἀλλὰ περὶ μὲν τῆς ἀπορίας ταύτης ἕτερος ἔστω λόγος ἆρα δὲ δεῖ τι ἀκίνητον εἶναι καὶ ἠρεμοῦν ἔξω τοῦ κινουμένου, μηδὲν ὃν ἐκείνου μόριον, ἢ οὔ;
But about this puzzle let there be another discussion. But must there be something unmoved and at rest outside that which is moved, being no part of it, or not?
καὶ τοῦτο πότερον καὶ ἐπὶ τοῦ παντὸς οὕτως ὑπάρχειν ἀναγκαῖον;
And must this also of necessity obtain in this way in the case of the whole?
ἴσως γὰρ ἂν δόξειεν ἄτοπον εἶναι, εἰ ἡ ἀρχὴ τῆς κινήσεως ἐντός.
For perhaps it would seem to be absurd if the principle of movement were inside.
διὸ δόξειεν ἂν τοῖς οὕτως ὑπολαμβάνουσιν εὖ εἰρῆσθαι Ὁμήρῳ
ἀλλ᾿ οὐκ ἂν ἐρύσαιτʼ ἐξ οὐρανόθεν πεδίονδε
Ζῆνʼ ὕπατον πάντων, οὐδʼ εἰ μάλα πολλὰ κάμοιτε· πάντες δʼ ἐξάπτεσθε θεοὶ πᾶσαί τε θέαιναι. τὸ γὰρ ὅλως ἀκίνητον ὑπʼ οὐδενὸς ἐνδέχεται κινηθῆναι.
Therefore, it would seem to those who assume so that Homer has spoken well: "But you could not drag down from heaven to the plain Zeus, the highest of all, not even if you should labor very much; hang on to him, all you gods and all you goddesses." For that which is entirely unmoved cannot possibly be moved by anything.
ὅθεν λύεται καὶ ἡ πάλαι λεχθεῖσα ἀπορία, πότερον ἐνδέχεται ἢ οὐκ ἐνδέχεται διαλυθῆναι τὴν τοῦ οὐρανοῦ σύστασιν, εἰ ἐξ ἀκίνητου ἤρτηται ἀρχῆς.
Whence also is solved the puzzle mentioned long ago, whether it is possible or not possible for the constitution of the heaven to be dissolved, if it is suspended from an unmoved principle.
ἐπὶ δὲ τῶν ζῴων οὐ μόνον τὸ οὕτως ἀκίνητον δεῖ ὑπάρχειν, ἀλλὰ καὶ ἐν αὐτοῖς τοῖς κινουμένοις κατὰ τόπον ὅσα κινεῖ αὐτὰ αὑτά.
But in the case of animals, not only must the thus unmoved exist, but also in the very things that are moved in place, as many as move themselves.
δεῖ γὰρ αὐτοῦ τὸ μὲν ἠρεμεῖν τὸ δὲ κινεῖσθαι, πρὸς ὃ ἀπερειδόμενον τὸ κινούμενον κινήσεται, οἷον ἄν τι κινῇ τῶν μορίων· ἀπερείδεται γὰρ θάτερον ὡς πρὸς μένον θάτερον.
For of it, one part must be at rest and the other be moved, against which as a support the moved part will move, for instance, if it moves any of its parts; for the one part supports itself as against the other which remains still.
περὶ δὲ τῶν ἀψύχων ὅσα κινεῖται ἀπορήσειεν ἄν τις, πότερον ἅπαντ’ ἔχει ἐν ἑαυτοῖς καὶ τὸ ἠρεμοῦν καὶ τὸ κινοῦν, καὶ πρὸς τῶν ἔξω τι ἠρεμούντων ἀπερείδεσθαι ἀνάγκη καὶ ταῦτα, ἢ ἀδύνατον, οἷον πῦρ ἢ γῆν ἢ τῶν ἀψύχων τι, ἀλλ᾿ ὑφʼ ὧν ταῦτα κινεῖται πρώτων.
But concerning inanimate things as many as are moved, one might puzzle whether they all have in themselves both that which is at rest and that which moves, and whether it is necessary for these also to support themselves against some of the things at rest outside, or whether this is impossible, as for instance fire or earth or any of the inanimate things, but they are moved by those things by which they are first moved.
πάντα γὰρ ὑπʼ ἄλλου κινεῖται τὰ ἄψυχα, ἀρχὴ δὲ πάντων τῶν οὕτως κινουμένων τὰ αὐτὰ αὑτὰ κινοῦντα.
For all inanimate things are moved by something else, and the principle of all things thus moved is the things that move themselves.
τῶν δὲ τοιούτων περὶ μὲν τῶν ζῴων εἴρηται· τὰ γὰρ τοιαῦτα πάντα ἀνάγκη καὶ ἐν αὐτοῖς ἔχειν τὸ ἠρεμοῦν, καὶ ἔξω πρὸς ὃ ἀπερείσεται.
And of such things, concerning animals it has been said; for all such things must have both in themselves that which is at rest, and outside that against which they will support themselves.
εἰ δέ τι ἐστὶν ἀνωτέρω καὶ πρώτως κινοῦν, ἄδηλον, καὶ ἄλλος λόγος περὶ τῆς τοιαύτης ἀρχῆς.
But whether there is something higher and primarily moving is unclear, and there is another discussion concerning such a principle.
τὰ δὲ ζῷα ὅσα κινεῖται, πάντα πρὸς τὰ ἔξω ἀπερειδόμενα κινεῖται, καὶ ἀναπνέοντα καὶ ἐκπνέοντα.
But all animals that are moved, move by supporting themselves against things outside, both when breathing in and breathing out.
οὐδὲν γὰρ διαφέρει μέγα ῥῖψαι βάρος ἢ μικρόν, ὅπερ ποιοῦσιν οἱ πτύοντες καὶ βήττοντες καὶ οἱ εἰσπνέοντες καὶ ἐκπνέοντες.
For it makes no difference to throw a great weight or a small one, which is what those do who spit and cough and those who breathe in and breathe out.