§5.4Τῶν δὲ χρωμάτων αἴτιον τοῖς μὲν ἄλλοις ζῴοις, καὶ τοῦ μονόχοοα εἶναι καὶ τοῦ ποικίλα, ἡ τοῦ δέρματος φύσις· τοῖς δ᾽ ἀνθρώποις οὐδὲν πλὴν τῶν πολιῶν, οὐ τῶν διὰ γῆρας ἀλλὰ τῶν διὰ νόσον·
On the other hand, the cause of colors in other animals, both of being of one color and of being variegated, is the nature of the skin; but in humans, it is the cause of nothing except gray hair, and not that due to old age but that due to disease.
ἐν γὰρ τῇ καλουμένῃ λεύκῃ λευκαὶ γίνονται αἱ τρίχες.
For in the so-called leuce, the hairs become white.
ἐὰν δ᾽ αἱ τρίχες ὦσι λευκαί, οὐκ ἀκολουθεῖ τῷ δέρματι ἡ λευκότης.
But even if the hairs are white, the whiteness does not accompany the skin.
αἴτιον δ᾽ ὅτι αἱ τρίχες ἐκ τοῦ δέρματος φύονται· ἐκ νενοσηκότος οὖν καὶ λευκοῦ τοῦ δέρματος καὶ ἡ θρὶξ συννοσεῖ, νόσος δὲ τριχὸς πολιότης ἐστίν, ἡ δὲ δι᾽ ἡλικίαν τῶν τριχῶν πολιότης γίνεται δι᾽ ἀσθένειαν καὶ ἔνδειαν θερμότητος.
And the cause is that the hairs grow out of the skin; therefore, from a diseased and white skin, the hair also shares in the disease, and the disease of hair is grayness. On the other hand, the graying of hairs due to age occurs because of weakness and a lack of heat.
καὶ γὰρ ἡλικία πᾶσα ῥέπει ἀποκλίνοντος τοῦ σώματος, καὶ ἐν τῷ γήρᾳ, ἐπὶ ψύξιν· τὸ γὰρ γῆρας ψυχρὸν καὶ ξηρόν ἐστιν.
For indeed, every age inclines, as the body declines, and in old age, towards cooling; for old age is cold and dry.
δεῖ δὲ νοῆσαι τὴν εἰς ἕκαστον μόριον ἀφικνουμένην τροφὴν ὅτι πέττει μὲν ἡ οἰκεία θερμότης, ἀδυναρτούσης δὲ φθείρεται καὶ πήρωσις γίνεται ἢ νόσος.
But one must understand, concerning the nourishment arriving at each part, that the proper heat concocts it, but when this heat fails, the nourishment is corrupted and mutilation or disease occurs.
ἀκριβέστερον δὲ περὶ τῆς τοιαύτης αἰτίας ὕστερον λεκτέον ἐν τοῖς περὶ αὐξήσεως καὶ τροφῆς.
But concerning this kind of cause, it must be stated more precisely later in the treatise On Growth and Nourishment.
ὅσοις οὖν τῶν ἀνθρώπων ὀλιγόθερμός ἐστιν ἡ τῶν τριχῶν φύσις καὶ πλείων ἡ εἰσιοῦσα ὑγρότης ἐστί, τῆς οἰκείας θερμότητος ἀδυνατούσης πέττειν σηπεται ὑπὸ τῆς ἐν τῷ περιέχοντι θερμότητος.
Therefore, in those of humans in whom the nature of the hairs has little heat and the incoming moisture is greater, since the proper heat is unable to concoct it, it is corrupted by the heat in the surrounding environment.
γίνεται δὲ σῆψις ὑπὸ θερμότητος μὲν πάσα, οὐ τῆς συμφύτου δέ, ὥσπερ εἴρηται ἐν ἑτέροις.
And all corruption is caused by heat, but not by the innate heat, as has been said in other places.
ἔστι δ᾽ ἡ σῆψις καὶ ὕδατος καὶ γῆς καὶ τῶν σωματικῶν πάντων τῶν τοιούτων, διὸ καὶ τῆς γεώδους ἀτμίδος, οἷον ὁ λεγόμενος εὐρώς· καὶ γὰρ ὁ εὐρώς ἐστι σαπρότης γεώδους ἀτμίδος.
And corruption occurs in water, earth, and all such bodily things, and therefore also in the earthy vapor, such as the so-called mold; for indeed mold is the decay of earthy vapor.
ὥστε καὶ ἡ ἐν ταῖς θριξὶ τοιαύτη οὖσα τροφὴ οὐ πεττομένη σήπεται, καὶ γίνεται ἡ καλουμένη πολιά.
So that the nourishment of this kind in the hairs, when not concocted, corrupts, and the so-called gray hair occurs.
λευκὴ δέ, ὅτι καὶ ὁ εὐρὼς μόνον τῶν σαπρῶν ὡς εἰπεῖν λευκόν ἐστιν.
And it is white because mold also is, so to speak, the only white thing among decayed things.
αἴτιον δὲ τούτου ὅτι πολὺν ἔχει ἀέρα· πᾶσα γὰρ ἡ γεώδης ἀτμὶς ἀέρος ἔχει δύναμιν παχέος.
And the cause of this is that it contains much air; for all earthy vapor has the power of thick air.
ὥσπερ γὰρ ἀντεστραμμένον τῇ πάχνῃ ὁ εὐρώς ἐστιν· ἂν μὲν γὰρ παγῇ ἡ ἀνιοῦσα ἀτμίς, πάχνη γίνεται, ἐὰν δὲ σαπῇ, εὐρώς.
For mold is, as it were, the converse of hoar-frost; for if the rising vapor is frozen, it becomes hoar-frost, but if it decays, it becomes mold.
διὸ καὶ ἐπιπολῆς ἐστὶν ἄμφω· ἡ γὰρ ἀτμὶς ἐπιπολῆς.
Therefore, both are on the surface; for the vapor is on the surface.
καὶ εὖ δὴ οἱ ποιηταὶ ἐν ταῖς κωμῳδίαις μεταφέρουσι σκώπτοντες, τὰς πολιὰς καλοῦντες γήρως εὐρῶτα καὶ πάχνην.
And indeed, the poets in comedies make good metaphors in jest, calling gray hairs the mold and hoar-frost of old age.
τὸ μὲν γὰρ τῷ γένει τὸ δὲ τῷ εἴδει ταὐτόν ἐστιν, ἡ μὲν πάχνη τῷ γένει (ἀτμὶς γὰρ ἄμφῶ), ὁ δὲ εὐρὼς τῷ εἴδει (σῆψις γὰρ ἄμφω).
For the one is the same in genus, and the other in species; hoar-frost in genus (for both are vapor), and mold in species (for both are corruption).
σημεῖον δ᾽ ὅτι τοιοῦτόν ἐστιν· καὶ γὰρ ἐκ νόσων πολλοῖς πολιαὶ ἀνέφυσαν, ὕστερον δ᾽ ὑγιασθεῖσι μέλαιναι ἀντὶ τούτων.
And the sign that it is of this nature is as follows: for indeed, from diseases, gray hairs grew on many people, but later when they recovered, black hairs grew instead of them.
αἴτιον δ᾽ ὅτι. ἐν τῇ ἀρρωστίᾳ, ὥσπερ καὶ τὸ ἄλλο σῶμα ἐν ἐνδείᾳ φυσικῆς θερμότητός ἐστιν, οὕτω καὶ τῶν ἄλλων μορίων καὶ τὰ πάνυ μικρὰ μετέχει τῆς ἀρρωστίας ταύτης.
And the cause is that in sickness, just as the rest of the body is in a state of deficiency of natural heat, so too of the other parts even the very small ones participate in this sickness.
περίττωμα δὲ πολὺ ἐγγίνεται ἐν τοῖς σώμασι καὶ τοῖς μορίοις· διόπερ ἡ ἐν ταῖς σαρξὶν ἀπεψία ποιεῖ τὰς πολιάς.
And much residue is generated in the bodies and the parts; therefore, the lack of concoction in the flesh produces gray hairs.
ὑγιάναντες δὲ καὶ ἰσχύσαντες πάλιν μεταβάλλουσι, καὶ γίνονται ὥσπερ ἐκ γερόντων νέοι· διὸ καὶ τὰ πάθη συμμεταβάλλουσιν ὀρθῶς δ᾽ ἔχει καὶ λέγειν τὴν μὲν νόσον γῆρας ἐπίκτητον, τὸ δὲ γῆρας νόσον φυσικήν· ποιοῦσι γοῦν νόσοι τινὲς ταὐτὰ ἅπερ καὶ τὸ γῆρας.
But having become healthy and strong again, they change back, and become as if young from being old; therefore, their conditions also change along with them. And it is also correct to say that disease is an acquired old age, and old age is a natural disease; at any rate, some diseases produce the same things that old age does.
τοὺς δὲ κροτάφους πολιοῦνται πρῶτον.
And they become gray on the temples first.
τὰ μὲν γὰρ ὄπισθεν κενὰ ὑγρότητός ἐστι διὰ τὸ μὴ ἔχειν ἐγκέφαλον, τὸ δὲ βρέγμα πολλὴν ἔχει ὑγρότητα· τὸ δὲ πολὺ οὐκ εὔσηπτον.
For the back parts of the head are empty of moisture because of not having the brain, while the crown of the head has much moisture; but what is much is not easily corrupted.
αἱ δ᾽ ἐν τοῖς κροτάφοις τρίχες οὔθ᾽ οὕτως ὀλίγον ἔχουσιν ὑγρὸν ὤστε πέττειν, οὔτε πολὺ ὥστε μὴ σήπεσθαι·
On the other hand, the hairs on the temples neither have so little moisture as to concoct it, nor so much as not to corrupt; for the place, being in the middle of both, is outside both conditions.
μέσος γὰρ ὢν ὁ τόπος ἀμφοτέρων ἐκτὸς ἀμφοτέρων τῶν παθῶν ἐστίν, περὶ μὲν οὖν τῆς τῶν ἀνθρώπων πολιότητος εἴρηται τὸ αἴτιον.
Concerning, then, the cause of grayness in humans, it has been discussed.