§5.3#1Τὰ δὲ τριχώματα διαφέρουσι καὶ πρὸς αὑτὰ τοῖς ἀνθρώποις κατὰ τὰς ἡλικίας καὶ πρὸς τὰ γένη τῶν ἄλλων ζῴων, ὅσαπερ ἔχει τρίχας αὐτῶν.
hair differs both in humans themselves according to age, and in comparison with the kinds of other animals, as many of them as have hair.
ἔχει δ᾽ ὅσαπερ ἐντὸς αὑτῶν ζῳοτοκεῖ πάντα σχεδόν· καὶ γὰρ τὰ ἀκανθώδεις ἔχοντα τῶν τοιούτων τριχῶν εἶδός τι ὑποληπτέον, οἷον τάς τε τῶν χερσαίων ἐχίνων καὶ εἴ τι ἄλλο τοιοῦτόν ἐστι τῶν ζῳοτόκων.
And almost all animals that are internally viviparous have hair; for we must assume that those among such animals that have prickly spines have a certain kind of hair, such as the spines of land hedgehogs and of any other such viviparous animal.
εἰσὶ δὲ διαφοραὶ τῶν τριχῶν κατά τε σκληρότητα καὶ μαλακότητα, καὶ κατὰ μῆκος καὶ βραχύτητα, καὶ εὐθύτητα καὶ οὐλότητα, καὶ πλῆθος καὶ ὀλιγότητα, πρὸς δὲ τούτοις κατὰ τὰς χρόας, κατὰ λευκότητα καὶ μελανίαν καὶ τὰς μεταξὺ τούτων.
And there are differences in hair in respect of hardness and softness, length and shortness, straightness and curliness, abundance and sparseness, and in addition to these, in color—namely, whiteness, blackness, and the intermediate shades.
ἐνίας δὲ τούτων τῶν διαφορῶν καὶ κατὰ τὰς ἡλικίας διαφέρουσι νέα τε καὶ παλαιούμενα.
And in some of these differences, animals differ also according to age, both when young and when growing old.
μάλιστα δὲ τοῦτ᾽ ἐπίδηλον ἐπὶ τῶν ἀνθρώπων· καὶ γὰρ δασύνεται μᾶλλον πρεσβύτερα γιγνόμενα, καὶ φαλακροῦνται τῆς κεφαλῆς ἔνιοι τὰ πρόσθεν.
And this is most manifest in the case of humans; for they become hairier as they grow older, and some become bald on the front parts of the head.
καὶ παῖδες μὲν ὄντες οὐ γίγνονται φαλακροί, οὐδ᾽ αἱ γυναῖκες· οἱ δ᾽ ἄνδρες προϊούσης ἤδη τῆς ἡλικίας.
And while they are children they do not become bald, nor do women; but men do so when their age is already advancing.
καὶ πολιοῦνται δὲ τὰς κεφαλὰς γηράσκοντες οἱ ἄνθρωποι.
And humans also turn grey on their heads as they grow old.
τῶν δ᾽ ἄλλων ζῴων οὐθενὶ τοῦθ᾽ ὡς εἰπεῖν γίνεται ἐπίδηλον, μάλιστα δ᾽ ἵππῳ τῶν ἄλλων.
And in none of the other animals, so to speak, does this become manifest, though most of all in the horse among the others.
καὶ φαλακροῦνται μὲν οἱ ἄνθρωποι τὰ ἔμπροσθεν τῆς κεφαλῆς, πολιοὶ δὲ πρῶτον γίνονται τοὺς κροτάφους· φαλακροῦται δ᾽ οὐθεὶς οὔτε τούτους οὔτε τὰ ὄπισθεν τῆς κεφαλῆς.
And indeed, humans become bald on the front parts of the head, and they first become grey at the temples; but no one becomes bald either on these or on the back of the head.
ὅσα δὲ τῶν ζῴων μὴ ἔχει τρίχας ἀλλὰ τὸ ἀνάλογον αὐταῖς, οἷον ὄρνιθες μὲν πτερά, τὸ δὲ τῶν ἰχθύων γένος λεπίδας, καὶ τούτοις συμβαίνει τῶν τοιούτων παθημάτων ἔνια κατὰ τὸν αὐτὸν λόγον.
And for as many of the animals as do not have hair but its analogue—such as birds having feathers, and the class of fish having scales—some of such affections happen to these as well according to the same principle.
τίνος μὲν οὖν ἕνεκα τὸ τῶν τριχῶν ἡ φύσις ἐποίησε γένος τοῖς ζῴοις, εἴρηται πρότερον ἐν ταῖς αἰτοίαις ταῖς περὶ τὰ μέρη τῶν ζῴων· τίνων δ᾽ ὑπαρχόντων καὶ διὰ τίνας ἀνάγκας συμβαίνει τούτων ἕκαστον, δηλῶσαι τῆς μεθόδου τῆς νῦν ἐστίν.
For what purpose, then, nature made the genus of hair for animals has been said before in the explanations concerning the parts of animals; but from what underlying conditions and through what necessities each of these things happens, it is the task of the present inquiry to show.
παχύτητος μὲν οὖν καὶ λεπτότητος αἴτιον μάλιστα τὸ δέρμα· τοῖς μὲν γὰρ παχὺ τοῖς δὲ λεπτόν, καὶ τοῖς μὲν μανὸν τοῖς δὲ πυκνόν ἐστιν.
Now, of thickness and thinness, the skin is the primary cause; for in some animals it is thick, in others thin, and in some loose-textured, in others dense.
ἔτι δὲ συναίτιον καὶ τῆς ἐνούσης ὑγρότητος ἡ διαφορά· τοῖς μὲν γὰρ ὑπάρχει λιπαρὰ τοῖς δ᾽ ὑδατώδης.
And furthermore, the difference in the inherent moisture is also a contributing cause; for in some it is oily, and in others watery.
ὅλως μὲν γὰρ ἡ τοῦ δέρματος φύσις ὑπόκειται γεώδης ἐπιπολῆς γὰρ οὖσα ἐξατμίζοντος τοῦ ὑγροῦ στερεὰ γίνεται καὶ γεώδης, αἱ δὲ τρίχες καὶ τὸ ἀνάλογον αὐταῖς οὐκ ἐκ τῆς σαρκὸς γίνονται ἀλλ᾽ ἐκ τοῦ δέρματος, ἐξατμίζοντος καὶ ἀναθυμιωμένου ἐν αὐτοῖς τοῦ ὑγροῦ.
For in general, the nature of the skin is fundamentally earthy; for being on the surface, as the moisture evaporates, it becomes solid and earthy; and the hairs and their analogue do not arise from the flesh but from the skin, as the moisture in them evaporates and is exhaled.
διὸ παχεῖαι μὲν ἐκ τοῦ παχέος, λεπταὶ δὲ ἐκ τοῦ λεπτοῦ δέρματος γίνονται.
Therefore, thick hairs arise from thick skin, and thin ones from thin skin.
ἂν μὲν οὖν ᾖ τὸ δέρμα μανότερον καὶ παχύτερον, παχεῖαι διά τε τὸ πλῆθος τοῦ γεώδους καὶ διὰ τὸ μέγεθος τῶν πόρων εἰσίν· ἂν δὲ πυκνότερον, λεπταὶ διὰ τὴν στενότητα τῶν πόρων.
If, then, the skin is looser and thicker, the hairs are thick both because of the abundance of the earthy matter and because of the size of the pores; but if it is denser, they are thin because of the narrowness of the pores.
ἔτι δ᾽ ἂν ᾖ ἡ ἰκμὰς ὑδατώδης, ταχὺ ἀναξηραινομένης οὐ λαμβάνουσι μέγεθος αἱ τρίχες, ἂν δὲ λιπαρά, τοὐναντίον· οὐ γὰρ εὐξήραντον τὸ λιπαρόν.
And furthermore, if the moisture is watery, since it dries up quickly, the hairs do not acquire size; but if it is oily, the opposite happens, for what is oily is not easily dried.
διόπερ ὅλως μὲν τὰ παχυδερμότερα παχυτριχώτερα τῶν ζῴων, οὐ μέντοι τὰ μάλιστα μᾶλλον, διὰ τὰς εἰρημένας αἰτίας, οἷον τὸ τῶν ὑῶν γένος πρὸς τὸ τῶν βοῶν πέπονθε καὶ πρὸς ἐλέφαντα καὶ πολλὰ τῶν ἄλλων.
Therefore, in general, those animals that are thicker-skinned have thicker hair, yet those that are extremely so are not necessarily more so, because of the reasons mentioned; as is the case with the genus of swine in relation to that of oxen, and to the elephant and many other animals.
διὰ τὴν αὐτὴν δ᾽ αἰτίαν καὶ αἱ ἐν τῇ κεφαλῇ τρίχες τοῖς ἀνθρώποις παχύταται· τοῦ γὰρ δέρματος τοῦτο παχύτατον καὶ ἐν πλείστῃ ὑγρότητι, ἔτι δ᾽ ἔχει μανότητα πολλήν.
And for the same reason, the hairs on the head are the thickest in humans; for this part of the skin is the thickest and has the most moisture, and furthermore, it has great looseness.
αἴτιον δὲ καὶ τοῦ μακρὰς ἢ βραχείας τὰς τρίχας εἶναι τὸ μὴ εὐξήραντον εἶναι τὸ ἐξατμίζον ὑγρόν.
And the cause of the hairs being long or short is also that the evaporating moisture is not easily dried up.
τοῦ δὲ μὴ εὐξήραντον εἶναι δύ᾽ αἰτίαι, τό τε ποσὸν καὶ τὸ ποιόν· ἄν τε γὰρ πολὺ ᾖ τὸ ὑγρόν, οὐκ εὐξήραντον, καὶ ἂν λιπαρόν.
And of its not being easily dried up, there are two causes: both quantity and quality; for if the moisture is abundant, it is not easily dried, and also if it is oily.