§4.2#2ἔτι δὲ περὶ τοῦ ἔνια μείζω τὸν ὄγκον ὄντα κουφότερα τῶν ἐλαττόνων εἶνα σωμάτων οὐδὲν ἐπεμνήσθησαν, οὐδὲ δῆλον πῶς ἐκ τῶν εἰρημένων ὁμολογούμενα τοῖς φαινομένοις συμβήσεται λέγειν αὐτοῖς.
Furthermore, they made no mention of the fact that some bodies, being larger in volume, are lighter than smaller bodies, nor is it clear how, from what they have said, they will succeed in speaking in agreement with the phenomena.
ἀναγκαῖον δὲ καὶ τοῖς περὶ τῆς τοῦ πυρὸς κουφότητος αἰτιωμένοις τὸ πολὺ κενὸν ἔχειν σχεδὸν ἐν ταῖς αὐταῖς ἐνέχεσθαι δυσχερείαις.
It is also necessary that those who attribute the lightness of fire to its having much void should fall into virtually the same difficulties.
ἔλαττον μὲν γὰρ ἕξει στερεὸν τῶν ἄλλων σωμάτων, καὶ τὸ κενὸν πλεῖον· ἀλλʼ ὅμως ἔσται τι πυρὸς πλῆθος ἐν ᾧ τὸ στερεὸν καὶ τὸ πλῆρες ὑπερβάλλει τῶν περιεχομένων στερεῶν ἔν τινι μικρῷ πλήθει γῆς.
For it will have less solid than other bodies, and more void; but nevertheless there will be some quantity of fire in which the solid and the full exceed the solids contained in some small quantity of earth.
ἐὰν δὲ φῶσι καὶ τὸ κενόν, πῶς διοριοῦσι τὸ ἀπλῶς βαρύ;
But if they say that they also take into account the void, how will they define the absolutely heavy?
ἢ γὰρ τῷ πλεῖον στερεὸν ἔχειν ἢ τῷ ἔλαττον κενόν.
For it must be either by having more solid or by having less void.
εἰ μὲν οὖν τοῦτο φήσουσιν, ἔσται τι πλῆθος γῆς οὕτως ὀλίγον ἐν ᾧ στερεὸν ἔσται 309b ἔλαττον ἢ ἐν πολλῷ πλήθει πυρός.
If, then, they say this, there will be some quantity of earth so small in which the solid will be less than in a large quantity of fire.
ὁμοίως δὲ κἂν τῷ κενῷ διορίσωσιν, ἔσται τι κουφότερον τοῦ ἀπλῶς κούφου καὶ φερομένου ἀεὶ ἄνω αὐτὸ φερόμενον ἀεὶ κάτω.
Likewise, even if they define it by the void, there will be something lighter than the absolutely light and that which is always carried upward, which is itself carried always downward.
τοῦτο δὲ ἀδύνατον· τὸ γὰρ ἀπλῶς κοῦφον ἀεὶ κουφότερον τῶν ἐχόντων βάρος καὶ κάτω φερομένων, τὸ δὲ κουφότερον οὐκ ἀεὶ κοῦφον διὰ τὸ λέγεσθαι καὶ ἐν τοῖς ἔχουσι βάρος ἕτερον ἑτέρου κουφότερον, οἷον γῆς ὕδωρ.
But this is impossible; for the absolutely light is always lighter than those which possess weight and are carried downward, whereas the lighter is not always light, because even among those possessing weight one is said to be lighter than another, as water is of earth.
ἀλλὰ μὴν οὐδὲ τῷ τὸ κενὸν ἀνάλογον ἔχειν πρὸς τὸ πλῆρες ἱκανὸν λῦσαι τὴν λεγομένην νῦν ἀπορίαν.
Nevertheless, not even by having the void in proportion to the full is it possible to solve the difficulty now mentioned.
συμβήσεται γὰρ καὶ τοῦτον τὸν τρόπον λέγουσιν ὡσαύτως τὸ ἀδύνατον.
For to those who speak in this way, the impossible will likewise occur.
ἐν γὰρ τῷ πλείονι πυρὶ καὶ ἐν τῷ ἐλάττονι τὸν αὐτὸν ἕξει λόγον τὸ στερεὸν πρὸς τὸ κενόν.
For in a larger quantity of fire and in a smaller, the ratio of the solid to the void will be the same.
φέρεται δέ γε θᾶττον τὸ πλεῖον ἄνω πῦρ τοῦ ἐλάττονος, καὶ κάτω δὲ πάλιν ὡσαύτως ὁ πλείων χρυσὸς καὶ ὁ μόλιβδος· ὁμοίως δὲ καὶ τῶν ἄλλων ἕκαστον τῶν ἐχόντων βάρος.
Yet a larger quantity of fire is carried upward faster than a smaller, and likewise downward, on the other hand, a larger quantity of gold and of lead; and similarly with each of the other things possessing weight.
οὐκ ἔδει δὲ τοῦτο συμβαίνειν, εἴπερ τούτῳ διώρισται τὸ βαρὺ καὶ κοῦφον.
But this ought not to happen, if indeed the heavy and light are defined by this.
ἄτοπον δὲ καὶ εἰ διὰ τὸ κενὸν μὲν ἄνω φέρονται, τὸ δὲ κενὸν αὐτὸ μή.
It is also absurd if they are carried upward because of the void, but the void itself is not.
ἀλλὰ μὴν εἴ γε τὸ μὲν κενὸν ἄνω πέφυκε φέρεσθαι, κάτω δὲ τὸ πλῆρες, καὶ διὰ τοῦτο τοῖς ἄλλοις αἴτια τῆς φορᾶς, οὐθὲν περὶ τῶν συνθέτων ἔδει σκοπεῖν διὰ τί τὰ μὲν κοῦφα τὰ δὲ βαρέα τῶν σωμάτοων, ἀλλὰ περὶ τούτων αὐτῶν εἰπεῖν διὰ τί τὸ μὲν κοῦφον, τὸ δʼ ἔχει βάρος, ἔτι δὲ τί τὸ αἴτιον τοῦ μὴ διεστάναι τὸ πλῆρες καὶ τὸ κενὸν ἀεί.
Yet, if indeed the void is naturally carried upward, and the full downward, and because of this they are the causes of motion for the other things, they ought not to have examined anything about composite bodies as to why some are light and others heavy, but to have spoken about these things themselves, as to why one is light and the other has weight, and further, what is the cause of the full and the void not being always separated.
ἄλογον δὲ καὶ τὸ χώραν τῷ κενῷ ποιεῖν, ὥσπερ οὐκ αὐτῷ χώραν τινὰ οὖσαν· ἀναγκαῖον δʼ εἴῦτερ κινεῖται τὸ κενόν, εἶναι αὐτοῦ τινὰ τόπον, ἐξ οὗ μεταβάλλει καὶ εἰς ὅν.
It is also unreasonable to make a place for the void, as if the void itself were not a kind of place; but if indeed the void moves, it is necessary that there be some place of it, from which it changes and into which it changes.
πρὸς δὲ τούτοις τί τῆς κινήσεως αἴτιον;
In addition to these points, what is the cause of the motion?
οὐ γὰρ δὴ τό γε κενόν· οὐ γὰρ αὐτὸ κινεῖται μόνον, ἀλλὰ καὶ τὸ στερεόν.
For surely it is not the void; for not only does the void itself move, but also the solid.
ὡσαύτως δὲ συμβαίνει κἂν τις ἄλλως διορίζῃ, μεγέθει καὶ σμικρότητι ποιῶν βαρύτερα καὶ κουφότερα θάτερα τῶν ἑτέρων, καὶ ἄλλον ὁντινοῦν τρόπον κατασκευάζων, μόνον δὲ τὴν αὐτὴν ὕλην ἅπασιν ἀποδιδούς, ἢ πλείους μὲν ὑπεναντίας δὲ μόνον.
Likewise, the same happens even if one defines them in some other way, making some things heavier and others lighter by magnitude and smallness, or constructing it in any other way whatsoever, provided only that one attributes the same matter to all, or more than one but only contrary matters.
μιᾶς μὲν γὰρ οὔσης οὐκ ἔσται τὸ ἀπλῶς βαρύ καὶ κοῦφον, ὥσπερ τοῖς ἐκ τῶν τριγώνων συνιστᾶσιν· ἐναντίας δέ, καθάπερ οἱ τὸ κενὸν καὶ πλῆρες, οὐκ ἔσται τὰ μεταξὺ τῶν ἁπλῶς βαρέων καὶ κούφων διὰ τίνʼ αἰτίαν βαρύτερα καὶ κουφότερα ἀλλήλων καὶ τῶν ἁπλῶν ἐστίν.
For if there is one matter, there will be no absolutely heavy and light, just as for those who construct them from triangles; whereas if they are contrary, as for those who assume the void and the full, there will be no explanation of the cause why the intermediates between the absolutely heavy and light are heavier and lighter than one another and than the absolute ones.
τὸ δὲ μεγέθει καὶ μικρότητι διορίζειν πεπλασμένῳ μὲν ἔοικε μᾶλλον τῶν πρότερον, ὅτι δʼ ἐνδέχεται καθʼ ἕκαστον ποιεῖν διαφορὰς τῶν τεττάρων στοιχείων, ἀσφαλεστέρως ἔχει πρὸς τὰς ἔμπροσθεν ἀπορίας.
On the other hand, to define them by magnitude and smallness seems more artificial than the previous theories, but because it is possible to make differences for each of the four elements, it is safer against the preceding difficulties.
τῷ δὲ μίαν ποιεῖν φύσιν τῶν τῷ μεγέθει διαφερόντων ἀναγκαῖον ταὐτὸν συμβαίνειν τοῖς μίαν ποιοῦσιν ὕλην, καὶ μήθʼ ἁπλῶς εἶναι μηθὲν κοῦφον μήτε φερόμενον ἄνω, ἀλλʼ ἢ ὑστερίζον ἢ ἐκθλιβόμενον, καὶ πολλὰ μικρὰ ὀλίγων μεγάλων βαρύτερα εἶναι.
But by making one nature for things that differ in magnitude, the same must necessarily happen as to those who make one matter, namely, that nothing is absolutely light nor carried upward, except by lagging behind or being squeezed out, and that many small things are heavier than a few large ones.
εἰ δὲ τοῦτο ἔσται, συμβήσεται πολὺν ἀέρα καὶ πολὺ πῦρ ὕδατος εἶναι βαρύτερα καὶ γῆς ὀλίγης.
If this is the case, it will follow that a large quantity of air and a large quantity of fire are heavier than water and a small quantity of earth.
τοῦτο δʼ ἐστὶν ἀδύνατον.
But this is impossible.
τὰ μὲν οὖν παρὰ τῶν ἄλλων εἰρημένα ταῦτα καὶ τοῦτον λέγεται τὸν τρόπον.
These, then, are the things said by the others, and they are stated in this way.