§5#3ὥστε ἀνοίγνυσθαι τοὺς πόρους ἐχρῆν ἐν ταῖς τοσαύταις ἐμπτώσεσιν εἰς τὴν ῥῖνα τοῦ πέριξ ἀέρος, ἀνοιχθέντων δὲ ἕπεσθαι τὴν αἴσθησιν τῶν ὀσμῶν.
Consequently, it would have been necessary for the passages to be opened during so many incursions of the surrounding air into the nose, and, once they were opened, for the perception of smells to follow.
εἴπερ οὖν οὐχ ἕπεται, τοὺς εἰρημένους πόρους ἀδύνατον ὑπάρχειν.
If, therefore, it does not follow, it is impossible for the aforementioned passages to exist.
οὐ μὴν οὐδὲ πιθανὸν, τὴν φύσιν ἐπιτεχνήσασθαί τι τοιοῦτον μηδενὸς ἕνεκα.
Nor indeed is it probable that nature contrived such a thing for no purpose.
εἰ γὰρ ἐπεποιήκει τινὰς αἰσθητικοὺς πόρους ὀσμῶν, οὐκ ἂν ἐπέφραξεν αὐτοὺς, ὥσπερ οὐδὲ τοὺς κατὰ τὰ ὦτα.
For if it had made any sensory passages of smells, it would not have blocked them, just as it did not block those near the ears.
βέλτιον γάρ ἐστι διὰ παντὸς ἑκάστην αἴσθησιν διαγνωστικὴν εἶναι τῶν ἰδίων αἰσθητῶν, οὐκ ἐν χρόνῳ μόνῳ τῷ τῆς εἰσπνοῆς.
For it is better for each sense to be diagnostic of its own sensible objects at all times, and not only at the time of inhalation.
οὐδὲ διὰ τοῦτο τοῖς ὀφθαλμοῖς ἐποίησεν ἡ φύσις ἐπιθέματα, διότι βέλτιον ἦν αὐτοὺς μὴ διὰ παντὸς ἐνεργεῖν, ἀλλὰ διὰ τὸ αὐτοὺς εἶναι μαλακοὺς, καὶ διὰ τοῦτο ὑπὸ τῶν προσπιπτόντων ῥᾳδίως βλάπτεσθαι, ἀφ’ ὦν ἵνα φρουρῶνται, ἡ φύσις αὐτοὺς τοῖς βλεφάροις ὠχύρωσεν οἷόν τισι προβλήμασι.
Nor for this reason did nature make coverings for the eyes, because it was better for them not to be active at all times, but because they are soft and therefore easily harmed by things falling upon them, to guard against which nature fortified them with eyelids like some kind of ramparts.
ἀμέλει καὶ αὐτὸς ὁ Ἀριστοτέλης εἴρηκεν, ὡς ἐν τοῖς σκληρὸν ἔχουσι ζώοις τὸν ἔξωθεν χιτῶνα τῶν ὀφθαλμῶν ἡ φύσις οὐκ ἐποίησε βλέφαρα, διότι δυσπαθεῖς εἰσιν, καὶ αὐτὸ καθ’ ἑαυτὸ οὐδὲν οὔτε προβλημάτων οὔτε στεγασμάτων οὔτε καλυμμάτων ἐπὶ τούτων χρῄζουσι τῶν ζώων, ἀλλ’ ἡμεῖς γε χρῄζομεν δεόντως, ἕνεκά τε τῶν εἰρημένων, κᾀπειδὰν ὕπνου καιρὸς ἥκῃ.
Indeed, even Aristotle himself has said that in animals that have a hard outer coat of the eyes, nature did not make eyelids, because they are not easily harmed, and of themselves they need neither ramparts nor shelters nor coverings in these animals; but we, at least, need them properly, both for the aforementioned reasons and when the time of sleep arrives.
ἀδύνατον γὰρ ἐν ἀέρι φῶς ἔχοντι καθυπνῶσαί τινα χωρὶς τοῦ σκεπασθῆναι τοὺς ὀφθαλμούς.
For it is impossible for anyone to sleep in air containing light without the eyes being covered.
οὕτω γοῦν καὶ αὐτοῖς ἐκείνοις τοῖς ζώοις, οἷς οὐκ ἔστι βλέφαρα, καράβοις, καὶ ἀστακοῖς, καὶ παγούροις, καὶ καρκίνοις, ἡ φύσις ἐποίησεν κοιλότητάς τινας, οἷον θαλάμους ὑποδεχομένους ὅλους τοὺς ὀφθαλμοὺς, ἐπειδὰν ὑπνοῦν ἐθέλωσιν· ὡς, ὅταν γε χρῆσθαι βουληθῶσιν αὐτοῖς, ἐξαίρουσιν ὅλους ὀρθίους ἅμα τοῖς αὐχέσιν, ἐφ’ ὧν βεβήκασιν, εἰς τὴν οἰκείαν ὀφθαλμοῖς καθιστῶντες χώραν, ἥπερ ἐστὶν ἐπὶ τῶν ὑψηλοτάτων ἐν τοῖς ζώοις μορίων.
In this way, at any rate, even for those animals that do not have eyelids, such as lobsters, crawfish, hermit crabs, and crabs, nature made certain cavities like chambers receiving the eyes entirely when they wish to sleep; so that whenever they wish to use them, they raise them all upright along with the necks on which they are mounted, restoring them to the proper place for eyes, which is on the highest parts in animals.
εἴρηται δὲ περὶ τῶν τοιούτων ἁπάντων αὐτάρκως ἐν τοῖς περὶ χρείας μορίων, ἅπερ εἴ τις ἀναλέξεται, γνώσεται μὲν καὶ τῶν βλεφάρων τὴν χρῆσιν, γνώσεται δὲ καὶ ὡς ἀεὶ τῇ φύσει πρόκειται ταῖς αἰσθήσεσιν ἐνεργεῖν.
Concerning all such matters, enough has been said in "On the Usefulness of the Parts", which if anyone reads, they will know both the use of the eyelids and also that it is always proposed by nature for the senses to be active.
εἰ δέ ποτ’ ἄλλου τινὸς ἕνεκα χρησιμωτέρου κατά τινα καιρὸν ἡσυχάζειν ἀναγκαῖον αὐταῖς ἐστιν, οὐδὲν τοῦτό γε ἀπόρημα τῷ λόγῳ.
But if at some time, for the sake of some other more useful purpose, it is necessary for them to be at rest at a certain time, this is no difficulty for the argument.
τὰ γὰρ μὴ δυνάμενα μετ’ ἀλλήλων ὑπάρχειν, οὐδ’ ἂν οἱ πάντες θεοὶ ζεῦξαι βουληθῶσιν, οἷόν τε αὐτοῖς ἐργάσασθαι τοῦτο.
For things that cannot exist together, not even if all the gods wished to yoke them together, would be able to bring this about for themselves.
ὅσα γοῦν ἀδύνατα τῇ σφῶν αὐτῶν φύσει, καὶ θεοῖς ἐστιν ἀδύνατα.
Indeed, whatever things are impossible by their own nature are impossible also for the gods.
μὴ τοίνυν θαύμαζε τὸ πῶς ἡ φύσις, ἀεὶ βουλομένη τὰς αἰσθήσεις ἐνεργεῖν, ἡσυχάζειν ἐπιτρέπει κατὰ τοὺς ὕπνους, βούλεται γὰρ ἐν τῷδε τὸν ὕπνον, ἀλλ’ ὅτι μᾶλλον.
Do not therefore wonder how nature, always wishing the senses to be active, permits them to be at rest during sleep, for in this situation it wills sleep, but rather more so.
οὐ μὴν οὐδ’ ἐν καιρῷ μοι νῦν ἐστιν ἐξηγεῖσθαι φύσεως ὕπνου· λέλεκται γὰρ ἐν ἑτέροις ὑπὲρ ἑκάστου τῶν φυσικῶν ἐν ἡμῖν ἔργων τε καὶ παθημάτων.
Nor indeed is it the right time for me now to explain the nature of sleep; for it has been discussed in other works concerning each of the natural works and affections in us.
εἴτ’ οὖν ἔργον ἐστὶ φυσικὸν, εἴτε πάθος ὁ ὕπνος, οὐδὲ γὰρ οὐδὲ τοῦτο εὐδιαίτητον, ἀδύνατον αὐτῷ τὰς αἰσθήσεις ἀκριβῶς αἰσθανομένας φυλάττειν.
Whether, therefore, sleep is a natural work or an affection—for indeed not even this is easy to determine—it is impossible for the senses to preserve themselves perceiving accurately during it.
οὔτ’ οὖν, ὅτι κατὰ τοὺς ὕπνους ἐνεργεῖν ὁμοίως οὐ δυνάμεθα ταῖς αἰσθήσεσιν, διὰ τοῦθ’ ὁ λόγος ἐστὶ ψευδὴς, ἄμεινον εἶναι φάσκων διὰ παντὸς ἑκάστην αἴσθησιν ἐνεργεῖν τοῦ διαλείπειν· οὔθ’, ὅτι φυλαττόμενοί τινα τῶν ἐμπιπτόντων τε καὶ προσπιπτόντων ἔξωθεν ἀναγκαζόμεθα κλείειν τὰ βλέφαρα, διὰ τοῦτ’ ἔστι μὴ ὁρᾷν τηνικαῦτα.
Neither, therefore, because we cannot be active with our senses in the same way during sleep, is the argument false which claims that it is better for each sense to be active at all times than to intermit; nor, because we are forced to close our eyelids to guard against things falling and striking from outside, is it for this reason better not to see at that time.
βέλτιον γὰρ, εἴπερ οἷόν τε ἦν ἀβλαβεῖς αὐτοὺς φυλάττεσθαι, καὶ τοῦθ’ ἡμᾶς ὁρᾷν.
For it would be better, if indeed it were possible for them to be kept unharmed, for us to see then as well.
ἐπειδὴ δ’ οὐχ οἷόν τε ἐνεργαζομένην, ἀναγκαζόμεθα κλείειν τὰ βλέφαρα.
But since it is not possible when they are active, we are forced to close our eyelids.
ταυτὶ μὲν οὖν εἰρήσθω μοι περὶ βλεφάρων χρείας· ἀπὸ γὰρ πολλῶν ὀλίγα, μηκύνειν γὰρ οὐ καιρός.
Let these things, then, be said by me concerning the use of eyelids; for I have said a few out of many, as it is not the time to protract the discussion.
μεταφέρωμεν ἤδη τὸν λόγον ἐπὶ τοὺς ὀσφρητικοὺς πόρους, οὓς Ἀριστοτέλης φησὶν ἐπιθέματα γεγονέναι πρὸς τῆς φύσεως, οὔτε χρείαν τινὰ εἰπὼν τῆς τοιαύτης κατασκευῆς, οὔτ’ ἀποδείξεις ὑπάρχειν.
Let us now transfer the argument to the olfactory passages, which Aristotle says have been made as coverings by nature, without having stated any use of such a structure, nor that proofs exist.
οὐ μόνον γὰρ οὐδενὸς ἕνεκα χρηστοῦ τοιοῦτοι γεγόνασιν, οἵους Ἀριστοτέλης αὐτοὺς εἶναι λέγει, ἀλλὰ καὶ βλάβην ἐργάζονται μεγάλην ἐν τῷ πλείονι χρόνῳ τῆς ζωῆς πηροῦντες ἡμῶν τὴν ὀσφρητικὴν αἴσθησιν, ὅπερ οὐδὲ κατὰ μίαν τῶν ἄλλων ὁρᾶται γεγονός.
For not only have they not been made for any good purpose, such as Aristotle says they are, but they also cause great harm, disabling our sense of smell for the greater part of our life, which is not seen to have happened in the case of any of the other senses.
ἐγρηγορότων γὰρ ἐνεργοῦσιν ἅπασαι διὰ παντὸς, ὅταν γε εὐπορῶσι τῶν οἰκείων αἰσθητῶν.
For when we are awake, all of them are active at all times, at least when they have an abundance of their own sensible objects.
ὅτι μὲν οὖν τὰ καλύμματα τῶν ὀσφρητικῶν πόρων ἄδηλός ἐστι καὶ ἀναπόδεικτος ὑπόθεσις, οὐδ’ ὑφ’ ἑνὸς τῶν ἐναργῶν μαρτυρουμένη, δεδειχέναι μοι δοκῶ.
That, therefore, the coverings of the olfactory passages are an unclear and unproven hypothesis, witnessed by none of the evident facts, I think I have shown.