§5Τὴν δ’ αἰτίαν περὶ τούτων ἁπάντων ἐντεῦθεν ἄν τις θεωρήσειεν.
And one might contemplate the cause of all these things from what follows.
Δεῖ γὰρ λαβεῖν ὅτι τὸ ζῷόν ἐστι φύσει ὑγρὸν καὶ θερμόν, καὶ τὸ ζῆν τοιοῦτον, τὸ δὲ γῆρας ψυχρὸν καὶ ξηρόν, καὶ τὸ τεθνηκός· φαίνεται γὰρ οὕτως.
For we must grasp that an animal is by nature moist and hot, and life is of this character, while old age is cold and dry, and so is that which has died; for so it appears.
Ὕλη δὲ τῶν σωμάτων τοῖς οὖσι ταῦτα, τὸ θερμὸν καὶ τὸ ψυχρόν, καὶ τὸ ξηρὸν καὶ τὸ ὑγρόν.
And the matter of the bodies for existing things is these: the hot and the cold, the dry and the moist.
Ἀνάγκη τοίνυν γηράσκοντα ξηραίνεσθαι.
It is necessary, therefore, that what grows old should dry up.
Διὸ δεῖ μὴ εὐξήραντον εἶναι τὸ ὑγρόν.
Therefore, the moisture must not be easily dried up.
Καὶ διὰ τοῦτο τὰ λιπαρὰ ἄσηπτα.
And for this reason, fatty substances do not rot.
Αἴτιον δ’ ὅτι ἀέρος· ὁ δ’ ἀὴρ πρὸς τἆλλα πῦρ· πῦρ δ’ οὐ γίνεται σαπρόν.
The cause is that it consists of air; and air, in comparison with the others, is fire; and fire does not become rotten.
Οὐδ’ αὖ ὀλίγον δεῖ εἶναι τὸ ὑγρόν· εὐξήραντον γὰρ καὶ τὸ ὀλίγον.
Nor again must the moisture be little; for even a little is easily dried up.
Διὸ καὶ τὰ μεγάλα καὶ ζῷα καὶ φυτὰ ὡς ὅλως εἰπεῖν μακροβιώτερα, καθάπερ ἐλέχθη πρότερον· εὔλογον γὰρ τὰ μείζω πλέον ἔχειν ὑγρόν.
Wherefore also large animals and plants are, to speak generally, longer-lived, as was said before; for it is reasonable that the larger have more moisture.
Οὐ μόνον δὲ διὰ τοῦτο μακροβιώτερα· δύο γὰρ τὰ αἴτια, τό τε ποσὸν καὶ τὸ ποιόν, ὥστε δεῖ μὴ μόνον πλῆθος εἶναι ὑγροῦ, ἀλλὰ τοῦτο καὶ θερμόν, ἵνα μήτε εὔπηκτον μήτε εὐξήραντον ᾖ.
And they are longer-lived not only for this reason; for the causes are two, namely quantity and quality, so that there must not only be an abundance of moisture, but this must also be hot, so that it may be neither easily congealed nor easily dried.
Καὶ διὰ τοῦτο ἄνθρωπος μακρόβιον μᾶλλον ἐνίων μειζόνων· μακροβιώτερα γὰρ τὰ λειπόμενα τῷ πλήθει τοῦ ὑγροῦ, ἐὰν πλείονι λόγῳ ὑπερέχῃ κατὰ τὸ ποιὸν ἢ λείπεται κατὰ τὸ ποσόν.
And for this reason man is longer-lived than some larger things; for those which fall short in the quantity of moisture are longer-lived, if they exceed in quality by a greater ratio than they fall short in quantity.
Ἔστι δ’ ἐνίοις μὲν τὸ θερμὸν τὸ λιπαρόν, ὃ ἅμα ποιεῖ τό τε μὴ εὐξήραντον καὶ τὸ μὴ εὔψυκτον· ἐνίοις δ’ ἄλλον ἔχει χυμόν.
And for some, the hot is the fatty, which at the same time makes it neither easily dried nor easily cooled; while for others, it has another humor.
Ἔτι δεῖ τὸ μέλλον εἶναι μὴ εὔφθαρτον μὴ περιττωματικὸν εἶναι.
Furthermore, that which is going to be indestructible must not be full of residue.
Ἀναιρεῖ γὰρ τὸ τοιοῦτον ἢ νόσῳ ἢ φύσει· ἐναντία δ’ ἡ τοῦ περιττώματος δύναμις καὶ φθαρτικὴ ἡ μὲν τῆς φύσεως ἡ δὲ μορίου.
For such a thing destroys either by disease or by nature; and the power of the residue is contrary and destructive, the one of nature as a whole, the other of a part.
Διὸ τὰ ὀχευτικὰ καὶ πολύσπερμα γηράσκει ταχύ· τὸ γὰρ σπέρμα περίττωμα, καὶ ἔτι ξηραίνει ἀπιόν.
Wherefore those that are prone to mating and have abundant semen age quickly; for semen is a residue, and moreover, by departing, it dries them up.
Καὶ διὰ τοῦτο ἡμίονος μακροβιώτερος ἵππου καὶ ὄνου, ἐξ ὧν ἐγένετο, καὶ τὰ θήλεα τῶν ἀρρένων, ἐὰν ὀχευτικὰ ᾖ τὰ ἄρρενα· διὸ οἱ στρουθοὶ οἱ ἄρρενες βραχυβιώτεροι τῶν θηλειῶν.
And for this reason, the mule is longer-lived than the horse and the ass from which it was generated, and females than males, if the males are prone to mating; wherefore male sparrows are shorter-lived than females.
Ἔτι δὲ καὶ ὅσα πονητικὰ τῶν ἀρρένων, καὶ διὰ τὸν πόνον γηράσκει μᾶλλον· ξηραίνει γὰρ ὁ πόνος, τὸ δὲ γῆρας ξηρόν ἐστιν.
Furthermore, those of the males that are laborious also age more on account of their labor; for labor dries, and old age is dry.
Φύσει δὲ καὶ ὡς ἐπὶ τὸ πᾶν εἰπεῖν τὰ ἄρρενα τῶν θηλειῶν μακροβιώτερα· αἴτιον δ’ ὅτι θερμότερον ζῷον τὸ ἄρρεν ἐστὶ τοῦ θήλεος.
But by nature and to speak generally, males are longer-lived than females; the cause is that the male is a hotter animal than the female.
Τὰ δ’ αὐτὰ ἐν τοῖς ἀλεεινοῖς μακροβιώτερά ἐστιν ἢ ἐν τοῖς ψυχροῖς τόποις, διὰ τὴν αὐτὴν αἰτίαν δι’ ἥνπερ τὰ μείζω.
And the same things are longer-lived in warm than in cold places, for the same cause for which the larger ones are.
Καὶ μάλιστ’ ἐπίδηλον τὸ μέγεθος τῶν τὴν φύσιν ψυχρῶν ζῴων· διὸ οἵ τ’ ὄφεις καὶ αἱ σαῦραι καὶ τὰ φολιδωτὰ μεγάλα ἐν τοῖς θερμοῖς τόποις, καὶ ἐν τῇ θαλάττῃ τῇ ἐρυθρᾷ τὰ ὀστρακόδερμα· τῆς τε γὰρ αὐξήσεως ἡ θερμὴ ὑγρότης αἰτία καὶ τῆς ζωῆς.
And the size of animals that are cold by nature is especially evident; wherefore snakes, lizards, and scaly animals are large in warm places, and in the Red Sea the testaceans; for hot moisture is the cause of both growth and life.
Ἐν δὲ τοῖς ψυχροῖς τόποις ὑδατωδέστερον τὸ ὑγρὸν τὸ ἐν τοῖς ζῴοις ἐστίν· διὸ εὔπηκτον, ὥστε τὰ μὲν οὐ γίνεται ὅλως τῶν ζῴων τῶν ὀλιγαίμων ἢ ἀναίμων ἐν τοῖς πρὸς τὴν ἄρκτον τόποις, οὔτε τὰ πεζὰ ἐν τῇ γῇ οὔτε τὰ ἔνυδρα ἐν τῇ θαλάττῃ, τὰ δὲ γίνεται μέν, ἐλάττω δὲ καὶ βραχυβιώτερα· ἀφαιρεῖται γὰρ ὁ πάγος τὴν αὔξησιν.
But in cold places, the moisture in animals is more watery; wherefore it is easily congealed, so that in the northern regions some of the scanty-blooded or bloodless animals do not exist at all, neither terrestrial ones on land nor aquatic ones in the sea, while others do exist, but are smaller and shorter-lived; for the frost deprives them of growth.
Τροφὴν δὲ μὴ λαμβάνοντα καὶ τὰ φυτὰ καὶ τὰ ζῷα φθείρονται· συντήκει γὰρ αὐτὰ ἑαυτά· ὥσπερ γὰρ ἡ πολλὴ φλὸξ κατακαίει καὶ φθείρει τὴν ὀλίγην τῷ τὴν τροφὴν ἀναλίσκειν, οὕτω τὸ φυσικὸν θερμὸν τὸ πρῶτον πεπτικὸν ἀναλίσκει τὴν ὕλην ἐν ᾗ ἐστίν.
And when they do not receive nourishment, both plants and animals are destroyed; for they consume themselves; for just as a large flame burns up and destroys a small one by consuming its fuel, so the natural heat, which is the primary digestive agent, consumes the matter in which it resides.
Τὰ δ’ ἔνυδρα τῶν πεζῶν ἧττον μακρόβια οὐχ ὅτι ὑγρὰ ἁπλῶς, ἀλλ’ ὅτι ὑδατώδη· τὸ δὲ τοιοῦτον ὑγρὸν εὔφθαρτον, ὅτι ψυχρὸν καὶ εὔπηκτον.
And aquatic animals are less long-lived than terrestrial ones, not because they are simply moist, but because they are watery; and such moisture is easily destroyed because it is cold and easily congealed.
Καὶ τὸ ἄναιμον διὰ τὸ αὐτό, ἐὰν μὴ μεγέθει ἀπαμύνηται· οὔτε γὰρ λίπος οὔτε γλυκὺ ἔχει.
And the bloodless animal is so for the same reason, unless it is protected by its size; for it has neither fat nor sweetness.
Ἐν γὰρ ζῴῳ τὸ λιπαρὸν γλυκύ· διὸ αἱ μέλιτται μακροβιώτεραι ἑτέρων μειζόνων ζῴων.
For in an animal, the fatty is sweet; wherefore bees are longer-lived than other larger animals.