§1.8#18 Διότι δʼ οὐδὲ πλείους οἷόν τʼ οὐρανούς εἶναι, λέγόμεν· τοῦτο γὰρ ἔφαμεν ἐπισκεπτέον, εἴ τις μὴ νομίζει καθόλου δεδεῖχθαι περὶ τῶν σωμάτων ὅτι ἀδύνατον ἐκτὸς εἶναι τοῦ κόσμου τοῦδε ὁτιοῦν αὐτῶν, ἀλλὰ μόνον ἐπὶ τῶν ἀορίστως κειμένων εἰρῆσθαι τόν λόγον.
8 Why there cannot be more worlds than one, let us now state; for we said that this must be investigated, in case anyone does not think it has been proved universally of bodies that it is impossible for any of them to be outside this world, but thinks that the argument was stated only of those assumed indefinitely.
ἅπαντα γάρ καὶ μένει καὶ κινεῖται βίᾳ καὶ κατὰ φύσιν, καὶ κατὰ φύσιν μέν, ἐν ᾧ μένει μὴ βίᾳ, καὶ φέρεται, καὶ εἰς ὃν φέρεται, καὶ μένει, ἐν ᾧ δὲ βίᾳ, καὶ φέρεται βίᾳ, καὶ εἰς ὃν βίᾳ φέρεται, βίᾳ καὶ μένει.
For all things both rest and move by force and according to nature; and it is according to nature for them to move to and rest in the place where they rest without force; and the place where they rest by force, they also move to by force, and where they are carried by force, they also rest by force.
ἔτι εἰ βίᾳ ἥδε ἡ φορά, ἡ ἐναντία κατὰ φύσιν.
Furthermore, if this motion is by force, the contrary motion is according to nature.
ἐπὶ δὴ τὸ μέσον τὸ ἐνταῦθα εἰ βίᾳ οἰσθήσεται ἡ γῇ ἐκεῖθεν, ἐντεῦθεν οἰσθήσεται ἐκεῖ κατὰ φύσιν· καὶ εἰ μένει ἐνταῦθα ἡ ἐκεῖθεν μὴ βίᾳ, καὶ οἰσθήσεται κατὰ φύσιν δεῦρο.
If, then, earth is carried from there to the center here by force, it will be carried from here to there according to nature; and if the earth from there rests here without force, it will also be carried hither according to nature.
μία δʼ ἡ κατὰ φύσιν.
But there is only one motion according to nature.
ἔτι ἀνάγκη πάντας τοὺς κόσμους ἐχ τῶν αὐτῶν εἶναι σωμάτων, ὁμοίους γʼ ὄντας τὴν φύσιν.
Furthermore, it is necessary that all the worlds consist of the same bodies, since they are similar in nature.
ἀλλὰ μὴν καὶ τῶν σωμάτων ἕκαστον ἀναγκαῖον τὴν αὺτήν ἔχειν δύναμιν, οἷον λέγω πῦρ καὶ γῆν καὶ τὰ μεταξύ τούτων· εἰ γὰρ ὁμώνυμα ταῦτα καὶ μὴ κατὰ τὴν αὐτὴν ἰδέαν λέγονται τἀκεῖ τοῖς παρʼ ἡμῖν, καὶ τὸ πᾶν ὁμωνύμως ἂν λέγοιτο κόσμος.
But indeed, it is also necessary for each of the bodies to have the same power—I mean, for instance, fire and earth and the intermediates; for if those things there are homonymous and not spoken of according to the same idea as those with us, the whole would also be called a 'world' only homonymously.
δῆλον τοίνυν ὅτι τὸ μὲν ἀπὸ τοῦ μέσου φέρεσθαι πέφυκε, τὸ δʼ ἐπὶ τὸ μέσον αὐτῶν, εἴπερ πἄν ὁμοειδὲς τὸ πῦρ τῷ πυρὶ καὶ τῶν ἄλλάων ἕκαστον, ὥσπερ καὶ τὰ ἐν τούτῳ μόρια τοῦ πυρός.
It is clear, then, that some of them are by nature carried away from the center, and others toward the center, if indeed all fire is of the same kind as fire, and each of the other elements likewise, just as the parts of fire in this world are.
ὅτι δʼ ἀνάγκη οὕτως ἔχειν, ἐκ τῶν περὶ τὰς κινήσεις ὑποθέσεωνφανερόν· αἵτε γὰρ κινήσεις πεπερασμέναι, ἕκαστόν τε τῶν στοιχείων λέγεται καθʼ ἑκάστην τῶν κινήσεων.
And that it must be so is clear from the assumptions concerning motions; for motions are finite, and each of the elements is spoken of in accordance with each of the motions.
ὥστʼ εἴπερ καὶ αἱ κινήσεις αἱ αὐταί, καὶ τὰ στοιχεῖα ἀνάγκη εἶναι πανταχοῦ ταὐτά.
So that if the motions are the same, the elements must also be the same everywhere.
πέφυκεν ἄρα φέρεσθαι καὶ ἐπὶ τόδε τὸ μέσον τὰ ἐν ἄλλῳ κόσμῳ τῆς γῆς μόρια, καὶ πρὸς τόδε τὸ ἔσχατον τὸ ἐκεῖ πῦρ: ἀλλʼ ἀδύνατον·
Therefore, the parts of earth in another world are also by nature carried toward this center here, and the fire there toward this extremity here.
τούτου γὰρ συμβαίνοντος ἀνάγκη φέρεσθαι ἄνω μὲν τὴν γῆν ἐν τῷ οἰκείῳ κόσμῳ, τὸ δὲ πῦρ ἐπὶ τό μέσον, ὁμοίως δὲ κοὶ τὴν ἐντεῦθεν γῆν ἀπὸ τοῦ μέσου φέρεσθαι κατὰ φύσιν, πρὸς τὸ ἐκεῖ φερομένην μέσον διὰ τὸ τοὺς κόσμους δὴ] δὲ ex uno codice Βekker. 273b 5. ὁμοειδὲς cum Simpl. Torstrik, ὁμοιοειδὲς Bekker. οὕτω κεῖσθαι πρὸς ἀλλήλους.
But this is impossible; for if this happens, it is necessary that in its own world earth is carried upward, and fire toward the center, and similarly that the earth from here is carried by nature away from the center, as it is carried toward the center there, because of the worlds being thus situated in relation to one another.
ἢ γὰρ οὐ θετέον τὴν αὐτὴν εἶναι φύσιν τῶν ἁπλῶν σωμάτων ἐν τοῖς πλείοσιν οὐρανοῖς, ἢ λέ. γοντας οὕτως τὸ μέσον ὲν ποιεῖν ἀνάγκη καὶ τὸ ἔσχατονʼ τούτου δʼ ὅντοςἀτόπουἀδύνατον εἶναι κόσμους πλείους ἑνός.
For either we must not assume that the nature of simple bodies is the same in the several heavens, or, if we say so, we must make the center one and the extremity one; but this being absurd, it is impossible for there to be more worlds than one.
τὸ δʼ ἀξιοῦν ἄλλην εἶναι φύσιν τῶν ἁπλῶν σωμάτων, ἄν ἀποσχῶσιν ἔλαττον ἢ πλεῖον τῶν οἰκείων τόπων, ἄλογον· τί γὰρ διαφέρει τοσονδὶ φάναι μῆκος ἀπέχειν ἢ τοσονδί;
But to claim that the nature of simple bodies is different if they are more or less distant from their proper places is unreasonable; for what difference does it make to say they are distant by this much length or by that much?
διοίσει γὰρ κατὰ λόγον, ὅσῳ πλεῖον μᾶλλον, τὸ δʼ εἶδος τὸ αὐτό.
For the difference will be proportional, greater as the distance is greater, but the form remains the same.
ἀλλὰ μὴν ἀνάγκη γʼ εἶναί τινα κίνησιν αὐτῶν· ὅτι μὲν γὰρ κινοῶνται, φανερόν.
But indeed, there must be some motion of them; for that they move is clear.
πότερον οὖν βίᾳ πάσας ἐροὔμεν κινεῖσθαι καὶ τὰς ἐναντίας;
Shall we say then that they move by force in all motions, even contrary ones?
ἀλλʼ ὃ μὴ πέφυκεν ὅλως κινεῖσθαι, ἀδόνατον τοῦτο κινεῖσθαι βίᾳ.
But that which has no nature at all to move cannot be moved by force.
εἰ τοίνυν ἐστί τις κίνησις αὐτῶν κατὰ φύσιν, ἀνάγκη τῶν ὁμοειδῶν καὶ τῶν καθʼ ἕκαστον πρὸς ἕνα ἀριθμῷ τόπον ὑπάρχειν τὴν κίνησιν, οἷον πρὸς τόδε τι μέσονκαὶ πρὸς τόδε τι ἔσχατον.
If, then, there is some motion of them according to nature, it is necessary that for things of the same kind, and for each individual, the motion is toward a place that is numerically one, as for instance toward this particular center and toward this particular extremity.
εἰ δὲ πρὸς εἴδει ταὐτά, πλείω δέ, διότι καὶ τὰ καθʼ ἕκαστα πλείω μέν, εἴδει δʼ ὅκαστον ἀδιάφορον, οὐ τῷ μὲντῷ δʼ οὐ τοιοῦτον ἔσται τῶν μορίων, ἀλλʼ ὁμοίως πᾶσιν· ὁμοίως γὰρ ἅπαντα κατʼ εἶδος ἀδιάφορα ἀλλήλων, ἀριθμῷ δʼ ἕτερον ὁτιοῦν ὁτουοῦν.
But if they are the same in species but multiple [in number], because the individuals are also multiple, though each is indistinguishable in species, it will not be that this is so for one part and not for another, but similarly for all; for similarly all are indistinguishable in species from one another, though any one is numerically different from any other.
λέγω δὲ τοῦτο, ὅτι εἰ τὰ ἐνταῦθα μόρια πρὸς ἄλληλα καὶ τά ἐν ἑτέρῳ κόσμῳ ὁμοίως ἔχει, καὶ τὸ ληφθὲν ἐντεῦθεν οὐδὲν διαφερόντως πρὸς τῶν ἐν ἄλλῳ τινὶ κόσμῳ μορίων καὶ πρὸς τῶν ἐν τῷ αὐτῷ, ἀλλʼ ὡσαύτως· διαφέρουσι γὰρ οὐθὲν εἴδει ἀλλήλων.
I say this because, if the parts here have a similar relation to one another as those in another world, any part taken from here will behave in no way differently toward the parts in another world than toward those in the same world, but in just the same way; for they differ in no way in species from one another.