---
title: "On the Natural Faculties · Περὶ φυσικῶν δυνάμεων"
author: "Galen"
translator: "Arthur John Brock"
languages: [grc, en]
shelf: "Classical Greek"
section: 4 of 9
url: https://scriptura.si/works/galen-on-the-natural-faculties/4/
cite: "Galen, tr. Arthur John Brock, On the Natural Faculties · Περὶ φυσικῶν δυνάμεων, section 4. Scriptura (scriptura.si), https://scriptura.si/works/galen-on-the-natural-faculties/4/"
---

# On the Natural Faculties · Περὶ φυσικῶν δυνάμεων

*Galen, tr. Arthur John Brock*

The great physician of Rome on how the body grows, nourishes itself and gets rid of waste, against the atomists who think nature works blindly.

> Greek: ed. A. J. Brock, from the Perseus Digital Library (canonical-greekLit, tlg0057.tlg010, CC BY-SA 4.0).

> English: Arthur John Brock, from the Perseus Digital Library (tlg0057.tlg010.perseus-eng2). Notes are not included.

> Rows follow the references the two texts share (books, chapters and sections), cut where both reach the end of a sentence.

## 4. Book II · sections 1–6

Source: https://scriptura.si/works/galen-on-the-natural-faculties/4/ · cite a paragraph as https://scriptura.si/works/galen-on-the-natural-faculties/4/#p-N

[¶0] 1. In the previous book we demonstrated that not only Erasistratus, but also all others who would say anything to the purpose about urinary secretion, must acknowledge that the kidneys possess some faculty which attracts to them this particular quality existing in the urine. Besides this we drew attention to the fact that the urine is not carried through the kidneys into the bladder by one method, the blood into parts of the animal by another, and the yellow bile separated out on yet another principle. For when once there has been demonstrated in any one organ, the drawing, or so-called epispastic faculty, there is then no difficulty in transferring it to the rest. Certainly Nature did not give a power such as this to the kidneys without giving it also to the vessels which abstract the biliary fluid, nor did she give it to the latter without also it to each of the other parts. And, assuredly, if this is true, we must marvel that Erasistratus should make statements concerning the delivery of nutriment from the food-canal which are so false as to be detected even by Asclepiades. Now, Erasistratus considers it absolutely certain that, if anything flows from the veins, one of two things must happen: either a completely empty space will result, or the contiguous quantum of fluid will run in and take the place of that which has been evacuated. Asclepiades, however, holds that not one of two, but one of three things must be said to result in the emptied vessels: either there will be an entirely empty space, or the contiguous portion will flow in, or the vessel will contract. For whereas, in the case of reeds and tubes it is true to say that, if these be submerged in water, and are emptied of the air which they contain in their lumens, then either a completely empty space will be left, or the contiguous portion will move onwards; in the case of veins this no longer holds, since their coats can collapse and so fall in upon the interior cavity. It may be seen, then, how false this hypothesis — by Zeus, I cannot call it a demonstration! — of Erasistratus is. And, from another point of view, even if it were true, it is superfluous, if the stomach has the power of compressing the veins, as he himself supposed, and the veins again of contracting upon their contents and propelling them forwards. For, apart from other considerations, no plethora would ever take place in the body, if delivery of nutriment resulted merely from the tendency of a vacuum to become refilled. Now, if the compression of the stomach becomes weaker the further it goes, and cannot reach to an indefinite distance, and if, therefore, there is need of some other mechanism to explain why the blood is conveyed in all directions, then the principle of the refilling of a vacuum may be looked on as a necessary addition; there will not, however, be a plethora in any of the parts coming after the liver, or, if there be, it will be in the region of the heart and lungs; for the heart alone of the parts which come after the liver draws the nutriment into its right ventricle, thereafter sending it through the arterioid vein to the lungs (for Erasistratus himself will have it that, owing to the membranous excrescences, no other parts save the lungs receive nourishment from the heart). If, however, in order to explain how plethora comes about, we suppose the force of compression by the stomach to persist indefinitely, we have no further need of the principle of the refilling of a vacuum, especially if we assume contraction of the veins in addition — as is, again, agreeable to Erasistratus himself.

> Greek: 1. Ὅτι μὲν οὖν ἀναγκαῖόν ἐστιν οὐκ Ἐρασιστράτῳ μόνον ἀλλὰ καὶ τοῖς ἄλλοις ἅπασιν, ὅσοι μέλλουσι περὶ διακρίσεως οὔρων ἐρεῖν τι χρηστόν, ὁμολογῆσαι δύναμίν τινʼ ὑπάρχειν τοῖς νεφροῖς ἕλκουσαν εἰς ἑαυτοὺς ποιότητα τοιαύτην, οἵα ἐν τοῖς οὔροις ἐστί, διὰ τοῦ πρόσθεν ἐπιδέδεικται γράμματος, ἀναμιμνησκόντων ἅμʼ αὐτῷ καὶ τοῦθʼ ἡμῶν, ὡς οὐκ ἄλλως μὲν εἰς τὴν κύστιν φέρεται τὰ οὖρα διὰ τῶν νεφρῶν, ἄλλως δʼ εἰς ἅπαντα τοῦ ζῴου τὰ μόρια τὸ αἷμα, κατʼ ἄλλον δέ τινα τρόπον ἡ ξανθὴ χολὴ διακρίνεται. δειχθείσης γὰρ ἐναργῶς ἐφʼ ἑνὸς οὑτινοσοῦν ὀργάνου τῆς ἑλκτικῆς τε καὶ ἐπισπαστικῆς ὀνομαζομένης δυνάμεως οὐδὲν ἔτι χαλεπὸν ἐπὶ τὰ λοιπὰ μεταφέρειν αὐτήν· οὐ γὰρ δὴ τοῖς μὲν νεφροῖς ἡ φύσις ἔδωκέ τινα τοιαύτην δύναμιν, οὐχὶ δέ γε καὶ τοῖς τὸ χολῶδες ὑγρὸν ἕλκουσιν ἀγγείοις οὐδὲ τούτοις μέν, οὐκέτι δὲ καὶ τῶν ἄλλων μορίων ἑκάστῳ. καὶ μὴν εἰ τοῦτʼ ἀληθές ἐστι, θαυμάζειν χρὴ τοῦ Ἐρασιστράτου ψευδεῖς οὕτω λόγους ὑπὲρ ἀναδόσεως τροφῆς εἰπόντος, ὡς μηδʼ Ἀσκληπιάδην λαθεῖν. καίτοι γʼ οἴεται παντὸς μᾶλλον ἀληθὲς ὑπάρχειν, ὡς, εἴπερ ἐκ τῶν φλεβῶν ἀπορρέοι τι, δυοῖν θάτερον ἢ κενὸς ἔσται τόπος ἀθρόως ἢ τὸ συνεχὲς ἐπιρρυήσεται τὴν βάσιν ἀναπληροῦν τοῦ κενουμένου. ἀλλʼ ὅ γʼ Ἀσκληπιάδης οὐ δυοῖν θάτερόν φησιν, ἀλλὰ τριῶν ἕν τι χρῆναι λέγειν ἐπὶ τοῖς κενουμένοις ἀγγείοις ἕπεσθαι ἢ κενὸν ἀθρόως τόπον ἢ τὸ συνεχὲς ἀκολουθήσειν ἢ συσταλήσεσθαι τὸ ἀγγεῖον. ἐπὶ μὲν γὰρ τῶν καλάμων καὶ τῶν αὐλίσκων τῶν εἰς τὸ ὕδωρ καθιεμένων ἀληθὲς εἰπεῖν, ὅτι κενουμένου τοῦ περιεχομένου κατὰ τὴν εὐρυχωρίαν αὐτῶν ἀέρος ἢ κενὸς ἀθρόως ἔσται τόπος ἢ ἀκολουθήσει τὸ συνεχές· ἐπὶ δὲ τῶν φλεβῶν οὐκέτʼ ἐγχωρεῖ, δυναμένου δὴ τοῦ χιτῶνος αὐτῶν εἰς ἑαυτὸν συνιζάνειν καὶ διὰ τοῦτο καταπίπτειν εἰς τὴν ἐντὸς εὐρυχωρίαν. οὕτω μὲν δὴ ψευδὴς ἡ περὶ τῆς πρὸς τὸ κενούμενον ἀκολουθίας οὐκ ἀπόδειξις μὰ Διʼ εἴποιμʼ ἂν ἀλλʼ ὑπόθεσις Ἐρασιστράτειος. καθʼ ἕτερον δʼ αὖ τρόπον, εἰ καὶ ἀληθὴς εἴη, περιττή, τῆς μὲν κοιλίας ἐνθλίβειν ταῖς φλεψὶ δυναμένης, ὡς αὐτὸς ὑπέθετο, τῶν φλεβῶν δʼ αὖ περιστέλλεσθαι τῷ ἐνυπάρχοντι καὶ προωθεῖν αὐτό. τά τε γὰρ ἄλλα καὶ πλῆθος οὐκ ἂν ἐν τῷ σώματι γένοιτο, τῇ πρὸς τὸ κενούμενον ἀκολουθίᾳ μόνῃ τῆς ἀναδόσεως ἐπιτελουμένης. εἰ μὲν οὖν ἡ τῆς γαστρὸς ἔνθλιψις ἐκλύεται προϊοῦσα καὶ μέχρι παντὸς ἀδυνατός ἐστιν ἐξικνεῖσθαι καὶ διὰ τοῦτʼ ἄλλης τινὸς δεῖ μηχανῆς εἰς τὴν πάντη φορὰν τοῦ αἵματος, ἀναγκαία μὲν ἡ πρὸς τὸ κενούμενον ἀκολουθία προσεξεύρηται· πλῆθος δʼ ἐν οὐδενὶ τῶν μεθʼ ἧπαρ ἔσται μορίων, ἤ, εἴπερ ἄρα, περὶ τὴν καρδίαν τε καὶ τὸν πνεύμονα. μόνη γὰρ αὕτη τῶν μεθʼ ἧπαρ εἰς τὴν δεξιὰν αὑτῆς κοιλίαν ἕλκει τὴν τροφήν, εἶτα διὰ τῆς φλεβὸς τῆς ἀρτηριώδους ἐκπέμπει τῷ πνεύμονι· τῶν γὰρ ἄλλων οὐδὲν οὐδʼ αὐτὸς ὁ Ἐρασίστρατος ἐκ καρδίας βούλεται τρέφεσθαι διὰ τὴν τῶν ὑμένων ἐπίφυσιν. εἰ δέ γʼ, ἵνα πλῆθος γένηται, φυλάξομεν ἄχρι παντὸς τὴν Ῥώμην τῆς κατὰ τὴν κοιλίαν ἐνθλίψεως, οὐδὲν ἔτι δεόμεθα τῆς πρὸς τὸ κενούμενον ἀκολουθίας, μάλιστʼ εἰ καὶ τὴν τῶν φλεβῶν συνυποθοίμεθα περιστολήν, ὡς αὖ καὶ τοῦτʼ αὐτῷ πάλιν ἀρέσκει τῷ Ἐρασιστράτῳ.

[¶1] 2. Let me draw his attention, then, once again, even if he does not wish it, to the kidneys, and let me state that these confute in the very clearest manner such people as object to the principle of attraction. Nobody has ever said anything plausible, nor, as we previously showed, has anyone been able to discover, by any means, any other cause for the secretion of urine; we necessarily appear mad if we maintain that the urine passes into the kidneys in the form of vapour, and we certainly cut a poor figure when we talk about the tendency of a vacuum to become refilled; this idea is foolish in the case of blood, and impossible, nay, perfectly nonsensical, in the case of the urine. This, then, is one blunder made by those who dissociate themselves from the principle of attraction. Another is that which they make about the secretion of yellow bile. For in this case, too, it is not a fact that when the blood runs past the mouths [stomata] of the bile-ducts there will be a thorough separation out [secretion] of biliary waste-matter. “Well,” say they, “let us suppose that it is not secreted but carried with the blood all over the body.” But, you sapient folk, Erasistratus himself supposed that Nature took thought for the animals' future, and was workmanlike in her method; and at the same time he maintained that the biliary fluid was useless in every way for the animals. Now these two things are incompatible. For how could Nature be still looked on as exercising forethought for the animal when she allowed a noxious humour such as this to be carried off and distributed with the blood?... This, however, is a small matter. I shall again point out here the greatest and most obvious error. For if the yellow bile adjusts itself to the narrower vessels and stomata, and the blood to the wider ones, for no other reason than that blood is thicker and bile thinner, and that the stomata of the veins are wider and those of the bile-ducts narrower, then it is clear that this watery and serous superfluity, too, will run out into the bile-ducts quicker than does the bile, exactly in proportion as it is thinner than the bile! How is it, then, that it does not run out? “Because,” it may be said, “urine is thicker than bile!” This was what one of our Erasistrateans ventured to say, herein clearly disregarding the evidence of his senses, although he had trusted these in the case of the bile and blood. For, if it be that we are to look on bile as thinner than blood because it runs more, then, since the serous residue passes through fine linen or lint or a or a sieve more easily even than does bile, by these tokens bile must also be thicker than the watery fluid. For here, again, there is no argument which will demonstrate that bile is thinner than the serous superfluities. But when a man shamelessly goes on using circumlocutions, and never acknowledges when he has had a fall, he is like the amateur wrestlers, who, when they have been overthrown by the experts and are lying on their backs on the ground, so far from recognizing their fall, actually seize their victorious adversaries by the necks and prevent them from getting away, thus supposing themselves to be the winners!

> Greek: 2. Ἀναμνηστέον οὖν αὖθις αὐτόν, κἂν μὴ βούληται, τῶν νεφρῶν καὶ λεκτέον, ὡς ἔλεγχος οὗτοι φανερώτατος ἁπάντων τῶν ἀποχωρούντων τῆς ὁλκῆς· οὐδεὶς γὰρ οὐδὲν οὔτʼ εἶπε πιθανόν, ἀλλʼ οὐδʼ ἐξευρεῖν εἶχε κατʼ οὐδένα τρόπον, ὡς ἔμπροσθεν ἐδείκνυμεν, ἕτερον αἴτιον οὔρων διακρίσεως, ἀλλʼ ἀναγκαῖον ἢ μαίνεσθαι δοκεῖν, εἰ φήσαιμεν ἀτμοειδῶς εἰς τὴν κύστιν ἴέναι τὸ οὖρον ἢ ἀσχημονεῖν τῆς πρὸς τὸ κενούμενον ἀκολουθίας μνημονεύοντας, ληρώδους μὲν οὔσης κἀπὶ τοῦ αἵματος, ἀδυνάτου δὲ καὶ ἠλιθίου παντάπασιν ἐπὶ τῶν οὔρων. Ν̔ μὲν δὴ τοῦτο σφάλμα τῶν ἀποστάντων τῆς ὁλκῆς· ἕτερον δὲ τὸ περὶ τῆς κατὰ τὴν ξανθὴν χολὴν διακρίσεως. οὐδὲ γὰρ οὐδʼ ἐκεῖ παραρρέοντος τοῦ αἵματος τὰ στόματα τῶν χοληδόχων ἀγγείων ἀκριβῶς διακριθήσεται τὸ χολῶδες περίττωμα. καὶ μὴ διακρινέσθω, φασίν, ἀλλὰ συναναφερέσθω τῷ αἵματι πάντη τοῦ σώματος. ἀλλʼ, ὦ σοφώτατοι, προνοητικὴν τοῦ ζῴου καὶ τεχνικὴν αὐτὸς ὁ Ἐρασίστρατος ὑπέθετο τὴν φυσιν. ἀλλὰ καὶ τὸ χολῶδες ὑγρὸν ἄχρηστον εἶναι πανταπάσι τοῖς ζῴοις ἔφασκεν. οὐ συμβαίνει δʼ ἀλλήλοις ἄμφω ταῦτα. πῶς γὰρ ἂν ἔτι προνοεῖσθαι τοῦ ζῴου δόξειεν ἐπιτρέπουσα συναναφέρεσθαι τῷ αἵματι μοχθηρὸν οὕτω χυμόν; ἀλλὰ ταῦτα μὲν σμικρά· τὸ δὲ μέγιστον καὶ σαφέστατον πάλιν ἐνταῦθʼ ἁμάρτημα καὶ δὴ φράσω. εἴπερ γὰρ διʼ οὐδὲν ἄλλʼ ἢ ὅτι παχύτερον μέν ἐστι τὸ αἷμα, λεπτοτέρα δʼ ἡ ξανθὴ χολὴ καὶ τὰ μὲν τῶν φλεβῶν εὐρύτερα στόματα, τὰ δὲ τῶν χοληδόχων ἀγγείων στενότερα, διὰ τοῦθʼ ἡ μὲν χολὴ τοῖς στενοτέροις ἀγγείοις τε καὶ στόμασιν ἐναρμόττει, τὸ δʼ αἷμα τοῖς εὐρυτέροις, δῆλον, ὡς καὶ τὸ ὑδατῶδες τοῦτο καὶ ὀρρῶδες περίττωμα τοσούτῳ πρότερον εἰσρυήσεται τοῖς χοληδόχοις ἀγγείοις, ὅσῳ λεπτότερόν ἐστι τῆς χολῆς. πῶς οὖν οὐκ εἰσρεῖ; ὅτι παχύτερόν ἐστι νὴ Δία τὸ οὖρον τῆς χολῆς· τοῦτο γὰρ ἐτόλμησέ τις εἰπεῖν τῶν καθʼ ἡμᾶς Ἐρασιστρατείων ἀποστὰς δηλονότι τῶν αἰσθήσεων, αἷς ἐπίστευσεν ἐπί τε τῆς χολῆς καὶ τοῦ αἵματος. εἴτε γὰρ ὅτι μᾶλλον ἡ χολὴ τοῦ αἵματος Ῥεῖ, διὰ τοῦτο λεπτοτέραν αὐτὴν ἡμῖν ἐστι νομιστέον, εἴθʼ ὅτι διʼ ὀθόνης ἢ Ῥάκους ἤ τινος ἠθμοῦ Ῥᾷον διεξέρχεται καὶ ταύτης τὸ ὀρρῶδες περίττωμα, κατὰ ταῦτα τὰ γνωρίσματα παχυτέρα τῆς ὑδατώδους ὑγρότητος καὶ αὕτη γενήσεται. πάλιν γὰρ οὐδʼ ἐνταῦθα λόγος οὐδείς ἐστιν, ὃς ἀποδείξει λεπτὸτέραν τὴν χολὴν τῶν ὀρρωδῶν περιττωμάτων. ἀλλʼ ὅταν τις ἀναισχυντῇ περιπλέκων τε καὶ μήπω καταπεπτωκέναι συγχωρῶν, ὅμοιος ἔσται τοῖς ἰδιώταις τῶν παλαιστῶν, οἳ καταβληθέντες ὑπὸ τῶν παλαιστρικῶν καὶ κατὰ τῆς γῆς ὕπτιοι κείμενοι τοσούτου δέουσι τὸ πτῶμα γνωρίζειν, ὥστε καὶ κρατοῦσι τῶν αὐχένων αὐτοὺς τοὺς καταβαλόντας οὐκ ἐῶντες ἀπαλλάττεσθαι, κἀν τούτῳ νικᾶν ὑπολαμβάνουσι.

[¶2] 3. Thus, every hypothesis of channels as an explanation of natural functioning is perfect nonsense. For, if there were not an inborn faculty given by Nature to each one of the organs at the very beginning, then animals could not continue to live even for a few days, far less for the number of years which they actually do. For let us suppose they were under no guardianship, lacking in creative ingenuity and forethought; let us suppose they were steered only by material forces, and not by any special faculties (the one attracting what is proper to it, another rejecting what is foreign, and yet another causing alteration and adhesion of the matter destined to nourish it); if we suppose this, I am sure it would be ridiculous for us to discuss natural, or, still more, psychical, activities — or, in fact, life as a whole.

> Greek: 3. λῆρος οὖν μακρὸς ἅπασα πόρων ὑπόθεσις εἰς φυσικὴν ἐνέργειαν. εἰ μὴ γὰρ δύναμίς τις σύμφυτος ἑκάστῳ τῶν ὀργάνων ὑπὸ τῆς φύσεως εὐθὺς ἐξ ἀρχῆς δοθείη, διαρκεῖν οὐ δυνήσεται τὰ ζῷα, μὴ ὅτι τοσοῦτον ἀριθμὸν ἐτῶν ἀλλʼ οὐδʼ ἡμερῶν ὀλιγίστων· ἀνεπιτρόπευτα γὰρ ἐάσαντες αὐτὰ καὶ τέχνης καὶ προνοίας ἔρημα μόναις ταῖς τῶν ὑλῶν οἰακιζόμενα Ῥοπαῖς, οὐδαμοῦ δυνάμεως οὐδεμιᾶς τῆς μὲν ἑλκούσης τὸ προσῆκον ἑαυτῇ, τῆς δʼ ἀπωθούσης τὸ ἀλλότριον, τῆς δʼ ἀλλοιούσης τε καὶ προσφυούσης τὸ θρέψον, οὐκ οἶδʼ ὅπως οὐκ ἂν εἴημεν καταγέλαστοι περί τε τῶν φυσικῶν ἐνεργειῶν διαλεγόμενοι καὶ πολὺ μᾶλλον ἔτι περὶ τῶν ψυχικῶν καὶ συμπάσης γε τῆς ζωῆς.

[¶3] For there is not a single animal which could live or endure for the shortest time if, possessing within itself so many different parts, it did not employ faculties which were attractive of what is appropriate, eliminative of what is foreign, and alterative of what is destined for nutrition. On the other hand, if we have these faculties, we no longer need channels, little or big, resting on an unproven hypothesis, for explaining the secretion of urine and bile, and the conception of some favourable situation (in which point alone Erasistratus shows some common sense, since he does regard all the parts of the body as having been well and truly placed and shaped by Nature).

> Greek: οὐδὲ γὰρ ζῆν οὐδὲ διαμένειν οὐδενὶ τῶν ζῴων οὐδʼ εἰς ἐλάχιστον χρόνον ἔσται δυνατόν, εἰ τοσαῦτα κεκτημένον ἐν ἑαυτῷ μόρια καὶ οὕτω διαφέροντα μήθʼ ἑλκτικῇ τῶν οἰκείων χρήσεται δυνάμει μήτʼ ἀποκριτικῇ τῶν ἀλλοτρίων μήτʼ ἀλλοιωτικῇ τῶν θρεψόντων. καὶ μὴν εἰ ταύτας ἔχοιμεν, οὐδὲν ἔτι πόρων μικρῶν ἢ μεγάλων ἐξ ὑποθέσεως ἀναποδείκτου λαμβανομένων εἰς οὔρου καὶ χολῆς διάκρισιν δεόμεθα καί τινος ἐπικαίρου θέσεως, ἐν ᾧ μόνῳ σωφρονεῖν ἔοικεν ὁ Ἐρασίστρατος ἅπαντα καλῶς τεθῆναί τε καὶ διαπλας θῆναι τὰ μόρια τοῦ σώματος ὑπὸ τῆς φύσεως οἰόμενος.

[¶4] But let us suppose he remained true to his own statement that Nature is “artistic” — this Nature which, at the beginning, well and truly shaped and disposed all the parts of the animal, and, after carrying out this function (for she left nothing undone), brought it forward to the light of day, endowed with certain faculties necessary for its very existence, and, thereafter, gradually increased it until it reached its due size. If he argued consistently on this principle, I fail to see how he can continue to refer natural functions to the smallness or largeness of canals, or to any other similarly absurd hypothesis. For this Nature which shapes and gradually adds to the parts is most certainly extended throughout their whole substance. Yes indeed, she shapes and nourishes and increases them through and through, not on the outside only. For Praxiteles and Phidias and all the other statuaries used merely to decorate their material on the outside, in so far as they were able to touch it; but its inner parts they left unembellished, unwrought, unaffected by art or forethought, since they were unable to penetrate therein and to reach and handle all portions of the material. It is not so, however, with Nature. Every part of a bone she makes bone, every part of the flesh she makes flesh, and so with fat and all the rest; there is no part which she has not touched, elaborated, and embellished. Phidias, on the other hand, could not turn wax into ivory and gold, nor yet gold into wax: for each of these remains as it was at the commencement, and becomes a perfect statue simply by being clothed externally in a form and artificial shape. But Nature does not preserve the original character of any kind of matter; if she did so, then all parts of the animal would be blood — that blood, namely, which flows to the semen from the impregnated female and which is, so to speak, like the statuary's wax, a single uniform matter, subjected to the artificer. From this blood there arises no part of the animal which is as red and moist [as blood is], for bone, artery, vein, nerve, cartilage, fat, gland, membrane, and marrow are not blood, though they arise from it.

> Greek: ἀλλʼ εἰ παρακολουθήσειεν ἑαυτῷ φύσιν ὀνομάζοντι τεχνικήν, εὐθὺς μὲν ἐξ ἀρχῆς ἅπαντα καλῶς διαπλάσασάν τε καὶ διαθεῖσαν τοῦ ζῴου τὰ μόρια, μετὰ δὲ τὴν τοιαύτην ἐνέργειαν, ὡς οὐδὲν ἔλειπεν, ἔτι προαγαγοῦσαν εἰς φῶς αὐτὸ σύν τισι δυνάμεσιν, ὧν ἄνευ ζῆν οὐκ ἠδύνατο, καὶ μετὰ ταῦτα κατὰ βραχὺ προσαυξήσασαν ἄχρι τοῦ πρέποντος μεγέθους, οὐκ οἶδα πῶς ὑπομένει πόρων σμικρότησιν ἢ μεγέθεσιν ἤ τισιν ἄλλαις οὕτω ληρώδεσιν ὑποθέσεσι φυσικὰς ἐνεργείας ἐπιτρέπειν. ἡ γὰρ διαπλάττουσα τὰ μόρια φύσις ἐκείνη καὶ κατὰ βραχὺ προσαύξουσα πάντως δήπου διʼ ὅλων αὐτῶν ἐκτέταται· καὶ γὰρ ὅλα διʼ ὅλων οὐκ ἔξωθεν μόνον αὐτὰ διαπλάττει τε καὶ τρέφει καὶ προσαύξει. Πραξιτέλης μὲν γὰρ ἢ Φειδίας ἤ τις ἄλλος ἀγαλματοποιὸς ἔξωθεν μόνον ἐκόσμουν τὰς ὕλας, καθὰ καὶ ψαύειν αὐτῶν ἠδύναντο, τὸ βάθος δʼ ἀκόσμητον καὶ ἀργὸν καὶ ἄτεχνον καὶ ἀπρονόητον ἀπέλιπον, ὡς ἂν μὴ δυνάμενοι κατελθεῖν εἰς αὐτὸ καὶ καταδῦναι καὶ θιγεῖν ἁπάντων τῆς ὕλης τῶν μερῶν. ἡ φύσις δʼ οὐχ οὕτως, ἀλλὰ τὸ μὲν ὀστοῦ μέρος ἅπαν ὀστοῦν ἀποτελεῖ, τὸ δὲ σαρκὸς σάρκα, τὸ δὲ πιμελῆς πιμελὴν καὶ τῶν ἄλλων ἕκαστον· οὐδὲν γάρ ἐστιν ἄψαυστον αὐτῇ μέρος οὐδʼ ἀνεξέργαστον οὐδʼ ἀκόσμητον. ἀλλὰ τὸν μὲν κηρὸν ὁ Φειδίας οὐκ ἠδύνατο ποιεῖν ἐλέφαντα καὶ χρυσόν, ἀλλʼ οὐδὲ τὸν χρυσὸν κηρόν· ἕκαστον γὰρ αὐτῶν μένον, οἷον ἦν ἐξ ἀρχῆς, ἔξωθεν μόνον ἠμφιεσμένον εἶδός τι καὶ σχῆμα τεχνικόν, ἄγαλμα τέλειον γέγονεν. ἡ φύσις δʼ οὐδεμιᾶς ἔτι φυλάττει τῶν ὑλῶν τὴν ἀρχαίαν ἰδέαν· αἷμα γὰρ ἂν ἦν οὕτως ἅπαντα τοῦ ζῴου τὰ μόρια, τὸ παρὰ τῆς κυούσης ἐπιρρέον τῷ σπέρματι, δίκην κηροῦ τινος ὕλη μία καὶ μονοειδὴς ὑποβεβλημένη τῷ τεχνίτῃ. γίγνεται δʼ ἐξ αὐτῆς οὐδὲν τῶν τοῦ ζῴου μορίων οὔτʼ ἐρυθρὸν οὕτως οὔθʼ ὑγρόν. ὀστοῦν γὰρ καὶ ἀρτηρία καὶ φλὲψ καὶ νεῦρον καὶ χόνδρος καὶ πιμελὴ καὶ ἀδὴν καὶ ὑμὴν καὶ μυελὸς ἄναιμα μέν, ἐξ αἵματος δὲ γέγονε.

[¶5] I would then ask Erasistratus himself to inform me what the altering, coagulating, and shaping agent is. He would doubtless say, “Either Nature or the semen,” meaning the same thing in both cases, but explaining it by different devices. For that which was previously semen, when it begins to procreate and to shape the animal, becomes, so to say, a special nature. For in the same way that Phidias possessed the faculties of his art even before touching his material, and then activated these in connection with this material (for every faculty remains inoperative in the absence of its proper material), so it is with the semen: its faculties it possessed from the beginning, while its activities it does not receive from its material, but it manifests them in connection therewith.

> Greek: τίνος ἀλλοιώσαντος καὶ τίνος πήξαντος καὶ τίνος διαπλάσαντος ἐδεόμην ἄν μοι τὸν Ἐρασίστρατον αὐτὸν ἀποκρίνασθαι. πάντως γὰρ ἂν εἶπεν ἤτοι τὴν φύσιν ἢ τὸ σπέρμα, ταὐτὸν μὲν λέγων καθʼ ἑκάτερον, διαφόροις δʼ ἐπινοίαις ἑρμηνεύων· ὃ γὰρ ἦν πρότερον σπέρμα, τοῦθʼ, ὅταν ἄρξηται φύειν τε καὶ διαπλάττειν τὸ ζῷον, φύσις τις γίγνεται. καθάπερ γὰρ ὁ Φειδίας εἶχε μὲν τὰς δυνάμεις τῆς τέχνης καὶ πρὶν ψαύειν τῆς ὕλης, ἐνήργει δʼ αὐταῖς περὶ τὴν ὕλην--ἅπασα γὰρ δύναμις ἀργεῖ ἀποροῦσα τῆς οἰκείας ὕλησ--, οὕτω καὶ τὸ σπέρμα τὰς μὲν δυνάμεις οἴκοθεν ἐκέκτητο, τὰς δʼ ἐνεργείας οὐκ ἐκ τῆς ὕλης ἔλαβεν, ἀλλὰ περὶ τὴν ὕλην ἐπεδείξατο.

[¶6] And, of course, if it were to be overwhelmed with a great quantity of blood, it would perish, while if it were to be entirely deprived of blood it would remain inoperative and would not turn into a nature. Therefore, in order that it may not perish, but may become a nature in place of semen, there must be an afflux to it of a little blood — or, rather, one should not say a little, but a quantity commensurate with that of the semen. What is it then that measures the quantity of this afflux? What prevents more from coming? What ensures against a deficiency? What is this third overseer of animal generation that we are to look for, which will furnish the semen with a due amount of blood? What would Erasistratus have said if he had been alive, and had been asked this question? Obviously, the semen itself. This, in fact, is the artificer analogous with Phidias, whilst the blood corresponds to the statuary's wax.

> Greek: καὶ μὴν εἰ πολλῷ μὲν ἐπικλύζοιτο τῷ αἵματι τὸ σπέρμα, διαφθείροιτʼ ἄν· εἰ δʼ ὅλως ἀποροίη παντάπασιν ἀργοῦν, οὐκ ἂν γένοιτο φύσις. ἵνʼ οὖν μήτε φθείρηται καὶ γίγνηται φύσις ἀντὶ σπέρματος, ὀλίγον ἐπιρρεῖν ἀναγκαῖον αὐτῷ τοῦ αἵματος, μᾶλλον δʼ οὐκ ὀλίγον λέγειν χρή, ἀλλὰ σύμμετρον τῷ πλήθει τοῦ σπέρματος. τίς οὖν ὁ μετρῶν αὐτοῦ τὸ ποσὸν τῆς ἐπιρροῆς; τίς ὁ κωλύων ἰέναι πλέον; τίς ὁ προτρέπων, ἵνʼ ἐνδεέστερον μὴ ἴῃ; τίνα ζητήσομεν ἐνταῦθα τρίτον ἐπιστάτην τοῦ ζῴου τῆς γενέσεως, ὃς χορηγήσει τῷ σπέρματι τὸ σύμμετρον αἷμα; τί ἂν εἶπεν Ἐρασίστρατος, εἰ ζῶν ταῦτʼ ἠρωτήθη; τὸ σπέρμα αὐτὸ δηλονότι· τοῦτο γάρ ἐστιν ὁ τεχνίτης ὁ ἀναλογῶν τῷ Φειδίᾳ, τὸ δʼ αἷμα τῷ κηρῷ προσέοικεν.

[¶7] Now, it is not for the wax to discover for itself how much of it is required; that is the business of Phidias. Accordingly the artificer will draw to itself as much blood as it needs. Here, however, we must pay attention and take care not unwittingly to credit the semen with reason and intelligence; if we were to do this, we would be making neither semen nor a nature, but an actual living animal. And if we retain these two principles — that of proportionate attraction, and that of the non-participation of intelligence — we shall ascribe to the semen a faculty for attracting blood similar to that possessed by the lodestone for iron. Here, then, again, in the case of the semen, as in so many previous instances, we have been compelled to acknowledge some kind of attractive faculty.

> Greek: οὔκουν πρέπει τὸν κηρὸν αὐτὸν ἑαυτῷ τὸ μέτρον ἐξευρίσκειν, ἀλλὰ τὸν Φειδίαν. ἕλξει δὴ τοσοῦτον αἵματος ὁ τεχνίτης εἰς ἑαυτόν, ὁπόσου δεῖται. ἀλλʼ ἐνταῦθα χρὴ προσέχειν ἤδη τὸν νοῦν καὶ σκοπεῖν, μή πως λάθωμεν τῷ σπέρματι λογισμόν τινα καὶ νοῦν χαρισάμενοι· οὕτω γὰρ ἂν οὔτε σπέρμα ποιήσαιμεν οὔτε φύσιν ἀλλʼ ἤδη ζῷον αὐτό. καὶ μὴν εἰ φυλάξομεν ἀμφότερα, τήν θʼ ὁλκὴν τοῦ συμμέτρου καὶ τὸ χωρὶς λογισμοῦ, δύναμίν τινα, καθάπερ ἡ λίθος ἑλκτικὴν εἶχε τοῦ σιδήρου, καὶ τῷ σπέρματι φήσομεν ὑπάρχειν αἵματος ἐπισπαστικήν. ἠναγκάσθημεν οὖν πάλιν κἀνταῦθα, καθάπερ ἤδη πολλάκις ἔμπροσθεν, ἑλκτικήν τινα δύναμιν ὁμολογῆσαι κατὰ τὸ σπέρμα.

[¶8] And what is the semen? Clearly the active principle of the animal, the material principle being the menstrual blood. Next, seeing that the active principle employs this faculty primarily, therefore, in order that any one of the things fashioned by it may come into existence, it [the principle] must necessarily be possessed of its own faculty. How, then, was Erasistratus unaware of it, if the primary function of the semen be to draw to itself a due proportion of blood? Now, this fluid would be in due proportion if it were so thin and vaporous, that, as soon as it was drawn like dew into every part of the semen, it would everywhere cease to display its own particular character; for so the semen will easily dominate and quickly assimilate it — in fact, will use it as food. It will then, I imagine, draw to itself a second and a third quantum, and thus by feeding it acquires for itself considerable bulk and quantity. In fact, the alterative faculty has now been discovered as well, although about this also has not written a word. And, thirdly the shaping faculty will become evident, by virtue of which the semen firstly surrounds itself with a thin membrane like a kind of superficial condensation; this is what was described by Hippocrates in the sixth-day birth, which, according to his statement, fell from the singing-girl and resembled the pellicle of an egg.

> Greek: τί δʼ ἦν τὸ σπέρμα; ἡ ἀρχὴ τοῦ ζῴου δηλονότι ἡ δραστική· ἡ γὰρ ὑλικὴ τὸ καταμήνιόν ἐστιν. εἶτʼ αὐτῆς τῆς ἀρχῆς πρώτῃ ταύτῃ τῇ δυνάμει χρωμένης, ἵνα γένηται τῶν ὑπʼ αὐτῆς τι δεδημιουργημένων, ἄμοιρον εἶναι τῆς οἰκείας δυνάμεως οὐκ νδέχεται. πῶς οὖν Ἐρασίστρατος αὐτὴν οὐκ οἶδεν, εἰ δὴ πρώτη μὲν αὕτη τοῦ σπέρματος ἐνέργ ια τὸ σύμμετρον αἵματος ἐπισπᾶσθαι πρὸς ἑαυτό; σύμμετρον δʼ ἂν εἴη τὸ λεπτὸν οὕτω καὶ ἀτμῶδες, ὥστʼ εὐθὺς εἰς πᾶν μόριον ἑλκόμενον τοῦ σπέρματος δροσοειδῶς μηδαμοῦ τὴν ἑαυτοῦ παρεμφαίνειν ἰδέαν. οὕτω γὰρ αὐτοῦ καὶ κρατήσει Ῥαδίως τὸ σπέρμα καὶ ταχέως ἐξομοιώσει καὶ τροφὴν ἑαυτῷ ποιήσεται κἄπειτʼ οἶμαι δεύτερον ἐπισπάσεται καὶ τρίτον, ὡς ὄγκον ἑαυτῷ καὶ πλῆθος ἀξιόλογον ἐργάσασθαι τραφέντι. καὶ μὴν ἤδη καὶ ἡ ἀλλοιωτικὴ δύναμις ἐξεύρηται μηδʼ αὐτὴ πρὸς Ἐρασιστράτου γεγραμμένη. τρίτη δʼ ἂν ἡ διαπλαστικὴ φανείη, καθʼ ἣν πρῶτον μὲν οἷον ἐπίπαγόν τινα λεπτὸν ὑμένα περιτίθησιν ἑαυτῷ τὸ σπέρμα, τὸν ὑφʼ Ἱπποκράτους ἐπὶ τῆς ἑκταίας γονῆς, ἣν ἐκπεσεῖν ἔλεγε τῆς μουσουργοῦ, τῷ τῶν ὠῶν εἰκασθέντα χιτῶνι· μετὰ δὲ τοῦτον ἤδη καὶ τἆλλʼ, ὅσα πρὸς ἐκείνου λέγεται διὰ τοῦ περὶ φύσιος παιδίου συγγράμματος.

[¶9] And following this all the other stages will occur, such as are described by him in his work “On the Child's Nature.” But if each of the parts formed were to remain as small as when it first came into existence, of what use would that be? They have, then, to grow. Now, how will they grow? By becoming extended in all directions and at the same time receiving nourishment.

> Greek: ἀλλʼ εἰ τῶν διαπλασθέντων ἕκαστον οὕτω μείνειε σμικρόν, ὡς ἐξ ἀρχῆς ἐγένετο, τί ἂν εἴη πλέον; αὐξάνεσθαι τοίνυν αὐτὰ χρή. πῶς οὖν αὐξηθήσεται; πάντη διατεινόμενα θʼ ἅμα καὶ τρεφόμενα. καί μοι τῶν ἔμπροσθεν εἰρημένων ἐπὶ τῆς κύστεως, ἣν οἱ παῖδες ἐμφυσῶντες ἔτριβον, ἀναμνησθεὶς μαθήσῃ μᾶλλον κἀκ τῶν νῦν Ῥηθησομένων.

[¶10] And if you will recall what I previously said about the bladder which the children blew up and rubbed, you will also understand my meaning better as expressed in what I am now about to say. Imagine the heart to be, at the beginning, so small as to differ in no respect from a millet-seed, or, if you will, a bean; and consider how otherwise it is to become large than by being extended in all directions and acquiring nourishment throughout its whole substance, in the way that, as I showed a short while ago, the semen is nourished. But even this was unknown to Erasistratus — the man who sings the artistic skill of Nature! He imagines that animals grow like webs, ropes, sacks, or baskets, each of which has, woven on to its end or margin, other material similar to that of which it was originally composed.

> Greek: ἐννόησον γὰρ δὴ τὴν καρδίαν οὕτω μὲν μικρὰν εἶναι κατʼ ἀρχάς, ὡς κέγχρου μηδὲν διαφέρειν ἤ, εἰ βούλει, κυάμου, καὶ ζήτησον, ὅπως ἂν ἄλλως αὕτη γένοιτο μεγάλη χωρὶς τοῦ πάντη διατεινομένην τρέφεσθαι διʼ ὅλης ἑαυτῆς, ὡς ὀλίγῳ πρόσθεν ἐδείκνυτο τὸ σπέρμα τρεφόμενον. ἀλλʼ οὐδὲ τοῦτʼ Ἐρασίστρατος οἶδεν ὁ τὴν τέχνην τῆς φύσεως ὑμνῶν, ἀλλʼ οὕτως αὐξάνεσθαι τὰ ζῷα νομίζει καθάπερ τινὰ κρησέραν ἢ σειρὰν ἢ σάκκον ἢ τάλαρον, ὧν ἑκάστῳ κατὰ τὸ πέρας ἐπιπλεκομένων ὁμοίων ἑτέρων τοῖς ἐξ ἀρχῆς αὐτὰ συντιθεῖσιν ἡ πρόσθεσις γίγνεται.

[¶11] But this, most sapient sir, is not growth, but genesis! For a bag, sack, garment, house, ship, or the like is said to be still coming into existence [undergoing genesis] so long as the appropriate form for the sake of which it is being constructed by the artificer is still incomplete. Then, when does it grow? Only when the basket, being complete, with a bottom, a mouth, and a belly, as it were, as well as the intermediate parts, now becomes larger in all these respects. “And how can this happen?” someone will ask. Only by our basket suddenly becoming an animal or a plant; for growth belongs to living things alone. Possibly you imagine that a house grows when it is being built, or a basket when being plated, or a garment when being woven? It is not so, however. Growth belongs to that which has already been completed in respect to its form, whereas the process by which that which is still becoming attains its form is termed not growth but genesis. That which is, grows, while that which is not, becomes.

> Greek: ἀλλὰ τοῦτό γʼ οὐκ αὔξησίς ἐστιν ἀλλὰ γένεσις, ὦ σοφώτατε· γίγνεται γὰρ ὁ θύλακος ἔτι καὶ ὁ σάκκος καὶ θοἰμάτιον καὶ ἡ οἰκία καὶ τὸ πλοῖον καὶ τῶν ἄλλων ἕκαστον, ὅταν μηδέπω τὸ προσῆκον εἶδος, οὗ χάριν ὑπὸ τοῦ τεχνίτου δημιουργεῖται, συμπεπληρωμένον ᾖ. πότʼ οὖν αὐξάνεται; ὅταν ἤδη τέλειος ὢν ὁ τάλαρος, ὡς ἔχειν πυθμένα τέ τινα καὶ στόμα καὶ οἷον γαστέρα καὶ τὰ τούτων μεταξύ, μείζων ἅπασι τούτοις γένηται. καὶ πῶς ἔσται τοῦτο; φήσει τις. πῶς δʼ ἄλλως ἢ εἰ ζῷον ἐξαίφνης ἢ φυτὸν ὁ τάλαρος ἡμῖν γένοιτο; μόνων γὰρ τῶν ζώντων ἡ αὔξησις. σὺ δʼ ἴσως οἴει τὴν οἰκίαν οἰκοδομουμένην αὐξάνεσθαι καὶ τὸν τάλαρον πλεκόμενον καὶ θοἰμάτιον ὑφαινόμενον. ἀλλʼ οὐχ ὧδʼ ἔχει· τοῦ μὲν γὰρ ἤδη συμπεπληρωμένου κατὰ τὸ εἶδος ἡ αὔξησις, τοῦ δʼ ἔτι γιγνομένου ἡ εἰς τὸ εἶδος ὁδὸς οὐκ αὔξησις ἀλλὰ γένεσις ὀνομάζεται· αὐξάνεται μὲν γὰρ τὸ ὄν, γίγνεται δὲ τὸ οὐκ ὄν.

[¶12] 4. This also was unknown to Erasistratus, whom nothing escaped, if his followers speak in any way truly in maintaining that he was familiar with the Peripatetic philosophers. Now, in so far as he acclaims Nature as being an artist in construction, even I recognize the Peripatetic teachings, but in other respects he does not come near them. For if anyone will make himself acquainted with the writings of Aristotle and Theophrastus, these will appear to him to consist of commentaries on the Nature-lore [physiology] of Hippocrates — according to which the principles of heat, cold, dryness and moisture act upon and are acted upon by one another, the hot principle being the most active, and the cold coming next to it in power; all this was stated in the first place by Hippocrates and secondly by Aristotle. Further, it is at once the Hippocratic and the Aristotelian teaching that the parts which receive that nourishment throughout their whole substance, and that, similarly, processes of mingling and alteration involve the entire substance. Moreover, that digestion is a species of alteration — a transmutation of the nutriment into the proper quality of the thing receiving it; that blood-production also is an alteration, and nutrition as well; that growth results from extension in all directions, combined with nutrition; that alteration is effected mainly by the warm principle, and that therefore digestion, nutrition, and the generation of the various humours, as well as the qualities of the surplus substances, result from the innate heat; all these and many other points besides in regard to the aforesaid faculties, the origin of diseases, and the discovery of remedies, were correctly stated first by Hippocrates of all writers whom we know, and were in the second place correctly expounded by Aristotle. Now, if all these views meet with the approval of the Peripatetics, as they undoubtedly do, and if none of them satisfy Erasistratus, what can the Erasistrateans possibly mean by claiming that their leader was associated with these philosophers? The fact is, they revere him as a god, and think that everything he says is true. If this be so, then we must suppose the Peripatetics to have strayed very far from truth, since they approve of none of the ideas of Erasistratus. And, indeed, the disciples of the latter produce his connection with the Peripatetics in order to furnish his Nature-lore with a respectable pedigree. Now, let us reverse our argument and put it in a different way from that which we have just employed. For if the Peripatetics were correct in their teaching about Nature, there could be nothing more absurd than the contentions of Erasistratus. And, I will leave it to the Erasistrateans themselves to decide; they must either advance the one proposition or the other. According to the former one the Peripatetics had no accurate acquaintance with Nature, and according to the second, Erasistratus. It is my task, then, to point out the opposition between the two doctrines, and theirs to make the choice.... But they certainly will not abandon their reverence for Erasistratus. Very well, then; let them stop talking about the Peripatetic philosophers. For among the numerous physiological teachings regarding the genesis and destruction of animals, their health, their diseases, and the methods of treating these, there will be found one only which is common to Erasistratus and the Peripatetics — namely, the view that Nature does everything for some purpose, and nothing in vain. But even as regards this doctrine their agreement is only verbal; in practice Erasistratus makes havoc of it a thousand times over. For, according to him, the spleen was made for no purpose, as also the omentum; similarly, too, the arteries which are inserted into kidneys — although these are practically the largest of all those that spring from the great artery [aorta]! And to judge by the Erasistratean argument, there must be countless other useless structures; for, if he knows nothing at all about these structures, he has little more anatomical knowledge than a butcher, while, if he is acquainted with them and yet does not state their use, he clearly imagines that they were made for no purpose, like the spleen. Why, however, should I discuss these structures fully, belonging as they do to the treatise “On the Use of Parts,” which I am personally about to complete? Let us, then, sum up again this same argument, and, having said a few words more in answer to the Erasistrateans, proceed to our next topic. The fact is, these people seem to me to have read none of Aristotle's writings, but to have heard from others how great an authority he was on “Nature,” and that those of the Porch follow in the steps of his Nature-lore; apparently they then discovered a single one of the current ideas which is common to Aristotle and Erasistratus, and made up some story of a connection between Erasistratus and these people. That Erasistratus, however, has no share in the Nature-lore of Aristotle is shown by an enumeration of the aforesaid doctrines, which emanated first from Hippocrates, secondly from Aristotle, thirdly from the Stoics (with a single modification, namely, that for them the qualities are bodies ). Perhaps, however, they will maintain that it was in the matter of logic that Erasistratus associated himself with the Peripatetic philosophers? Here they show ignorance of the fact that these philosophers never brought forward false or inconclusive arguments, while the Erasistratean books are full of them. So perhaps somebody may already be asking, in some surprise, what possessed Erasistratus that he turned so completely from the doctrines of Hippocrates, and why it is that he takes away the attractive faculty from the biliary passages in the liver — for we have sufficiently discussed the kidneys — alleging [as the cause of bile-secretion] a favourable situation, the narrowness of vessels, and a common space into which the veins from the gateway [of the liver] conduct the unpurified blood, and from which, in the first place, the [biliary] passages take over the bile, and secondly, the [branches] of the vena cava take over the purified blood. For it would not only have done him no harm to have mentioned the idea of attraction, but he would thereby have been able to get rid of countless other disputed questions.

> Greek: 4. καὶ ταῦτʼ Ἐρασίστρατος οὐκ οἶδεν, ὃν οὐδὲν λανθάνει, εἴπερ ὅλως ἀληθεύουσιν οἱ ἀπʼ αὐτοῦ φάσκοντες ὡμιληκέναι τοῖς ἐκ τοῦ περιπάτου φιλοσόφοις αὐτόν. ἄχρι μὲν οὖν τοῦ τὴν φύσιν ὑμνεῖν ὡς τεχνικὴν κἀγὼ γνωρίζω τὰ τοῦ περιπάτου δόγματα, τῶν δʼ ἄλλων οὐδὲν οὐδʼ ἐγγύς. εἰ γάρ τις ὁμιλήσειε τοῖς Ἀριστοτέλους καὶ Θεοφράστου γράμμασι, τῆς Ἱπποκράτους ἂν αὐτὰ δόξειε φυσιολογίας ὑπομνήματα συγκεῖσθαι, τὸ θερμὸν καὶ τὸ ψυχρὸν καὶ τὸ ξηρὸν καὶ τὸ ὑγρὸν εἰς ἄλληλα δρῶντα καὶ πάσχοντα καὶ τούτων αὐτῶν δραστικώτατον μὲν τὸ θερμόν, δεύτερον δὲ τῇ δυνάμει τὸ ψυχρὸν Ἱπποκράτους ταῦτα σύμπαντα πρώτου, δευτέρου δʼ Ἀριστοτέλους εἰπόντος. τρέφεσθαι δὲ διʼ ὅλων αὑτῶν τὰ τρεφόμενα καὶ κεράννυσθαι διʼ ὅλων τὰ κεραννύμενα καὶ ἀλλοιοῦσθαι διʼ ὅλων τὰ ἀλλοιούμενα, καὶ ταῦθʼ Ἱπποκράτειά θʼ ἅμα καὶ Ἀριστοτέλεια. καὶ τὴν πέψιν ἀλλοίωσίν τινʼ ὑπάρχειν καὶ μεταβολὴν τοῦ τρέφοντος εἰς τὴν οἰκείαν τοῦ τρεφομένου ποιότητα, τὴν δʼ ἐξαιμάτωσιν ἀλλοίωσιν εἶναι καὶ τὴν θρέψιν ὡσαύτως καὶ τὴν αὔξησιν ἐκ τῆς πάντη διατάσεως καὶ θρέψεως γίγνεσθαι, τὴν δʼ ἀλλοίωσιν ὑπὸ τοῦ θερμοῦ μάλιστα συντελεῖσθαι καὶ διὰ τοῦτο καὶ τὴν πέψιν καὶ τὴν θρέψιν καὶ τὴν τῶν χυμῶν ἁπάντων γένεσιν, ἤδη δὲ καὶ τοῖς περιττώμασι τὰς ποιότητας ὑπὸ τῆς ἐμφύτου θερμασίας ἐγγίγνεσθαι, ταῦτα σύμπαντα καὶ πρὸς τούτοις ἕτερα πολλὰ τά τε τῶν προειρημένων δυνάμεων καὶ τὰ τῶν νοσημάτων τῆς γενέσεως καὶ τὰ τῶν ἰαμάτων τῆς εὑρέσεως Ἱπποκράτης μὲν πρῶτος ἁπάντων ὧν ἴσμεν ὀρθῶς εἶπεν, Ἀριστοτέλης δὲ δεύτερος ὀρθῶς ἐξηγήσατο. καὶ μὴν εἰ ταῦτα σύμπαντα τοῖς ἐκ τοῦ περιπάτου δοκεῖ, καθάπερ οὖν δοκεῖ, μηδὲν δʼ αὐτῶν ἀρέσκει τῷ Ἐρασιστράτῳ, τί ποτε βούλεται τοῖς Ἐρασιστρατείοις ἡ προς τοὺς φιλοσόφους ἐκείνους τοῦ τῆς αἱρέσεως αὐτῶν ἡγεμόνος ὁμιλία; θαυμάζουσι μὲν γὰρ αὐτὸν ὡς θεὸν καὶ πάντʼ ἀληθεύειν νομίζουσιν. εἰ δʼ οὕτως ἔχει ταῦτα, πάμπολυ δήπου τῆς ἀληθείας ἐσφάλθαι χρὴ νομίζειν τοὺς ἐκ τοῦ περιπάτου φιλοσόφους, οἷς μηδὲν ὧν Ἐρασίστρατος ὑπελάμβανεν ἀρέσκει. καὶ μὴν ὥσπερ τινʼ εὐγένειαν αὐτῷ τῆς φυσιολογίας τὴν πρὸς τοὺς ἄνδρας ἐκείνους συνουσίαν ἐκπορίζουσι. πάλιν οὖν ἀναστρέψωμεν τὸν λόγον ἑτέρως ἢ ὡς ὀλίγῳ πρόσθεν ἐτύχομεν εἰπόντες. εἴπερ γὰρ οἱ ἐκ τοῦ περιπάτου καλῶς ἐφυσιολόγησαν, οὐδὲν ἂν εἴη ληρωδέστερον Ἐρασιστράτου καὶ δίδωμι τοῖς Ἐρασιστρατείοις αὐτοῖς τὴν αἵρεσιν· ἢ γὰρ τὸν πρότερον λόγον ἢ τοῦτον προσήσονται. λέγει δʼ ὁ μὲν πρότερος οὐδὲν ὀρθῶς ἐγνωκέναι περὶ φύσεως τοὺς περιπατητικούς, ὁ δὲ δεύτερος Ἐρασίστρατον. ἐμὸν μὲν οὖν ὑπομνῆσαι τῶν δογμάτων τὴν μάχην, ἐκείνων δʼ ἡ αἵρεσις. ἀλλʼ οὐκ ἂν ἀποσταῖεν τοῦ θαυμάζειν Ἐρασίστρατον· οὐκοῦν σιωπάτωσαν περὶ τῶν ἐκ τοῦ περιπάτου φιλοσόφων. παμπόλλων γὰρ ὄντων δογμάτων φυσικῶν περί τε γένεσιν καὶ φθορὰν τῶν ζῴων καὶ ὑγίειαν καὶ νόσους καὶ τὰς θεραπείας αὐτῶν ἓν μόνον εὑρεθήσεται ταὐτὸν Ἐρασιστράτῳ κἀκείνοις τοῖς ἀνδράσι, τό τινος ἕνεκα πάντα ποιεῖν τὴν φύσιν καὶ μάτην μηδέν. ἀλλὰ καὶ αὐτὸ τοῦτο μέχρι λόγου κοινόν, ἔργῳ δὲ μυριάκις Ἐρασίστρατος αὐτὸ διαφθείρει· μάτην μὲν γὰρ ὁ σπλὴν ἐγένετο, μάτην δὲ τὸ ἐπίπλοον, μάτην δʼ αἱ εἰς τοὺς νεφροὺς ἀρτηρίαι καταφυόμεναι, σχεδὸν ἁπασῶν τῶν ἀπὸ τῆς μεγάλης ἀρτηρίας ἀποβλαστανουσῶν οὖσαι μέγισται, μάτην δʼ ἄλλα μυρία κατά γε τὸν Ἐρασιστράτειον λόγον· ἅπερ εἰ μὲν οὐδʼ ὅλως γιγνώσκει, βραχεῖ μαγείρου σοφώτερός ἐστιν ἐν ταῖς ἀνατομαῖς, εἰ δʼ εἰδὼς οὐ λέγει τὴν χρείαν αὐτῶν, οἴεται δηλονότι παραπλησίως τῷ σπληνὶ μάτην αὐτὰ γεγονέναι. καίτοι τί ταῦτʼ ἐπεξέρχομαι τῆς περὶ χρείας μορίων πραγματείας ὄντα μελλούσης ἡμῖν ἰδίᾳ περαίνεσθαι; πάλιν οὖν ἀναλάβωμεν τὸν αὐτὸν λόγον εἰπόντες τέ τι βραχὺ πρὸς τοὺς Ἐρασιστρατείους ἔτι τῶν ἐφεξῆς ἐχώμεθα. δοκοῦσι γάρ μοι μηδὲν ἀνεγνωκέναι τῶν Ἀριστοτέλους οὗτοι συγγραμμάτων, ἀλλʼ ἄλλων ἀκούοντες, ὡς δεινὸς ἦν περὶ φύσιν ὁ ἄνθρωπος καὶ ὡς οἱ ἀπὸ τῆς στοᾶς κατʼ ἴχνη τῆς ἐκείνου φυσιολογίας βαδίζουσιν, εἶθʼ εὑρόντες ἕν τι τῶν περιφερομένων δογμάτων κοινὸν αὐτῷ πρὸς Ἐρασίστρατον ἀναπλάσαι τινὰ συνουσίαν αὐτοῦ πρὸς ἐκείνους τοὺς ἄνδρας. ἀλλʼ ὅτι μὲν τῆς Ἀριστοτέλους φυσιολογίας οὐδὲν Ἐρασιστράτῳ μέτεστιν, ὁ κατάλογος τῶν προειρημένων ἐνδείκνυται δογμάτων, ἃ πρώτου μὲν Ἱπποκράτους ἦν, δευτέρου δʼ Ἀριστοτέλους, τρίτων δὲ τῶν Στωϊκῶν, ἑνὸς μόνου μετατιθεμένου τοῦ τὰς ποιότητας εἶναι σώματα. τάχα δʼ ἂν τῆς λογικῆς ἕνεκα θεωρίας ὡμιληκέναι φαῖεν τὸν Ἐρασίστρατον τοῖς ἐκ τοῦ περιπάτου φιλοσόφοις, οὐκ εἰδότες, ὡς ἐκεῖνοι μὲν ψευδεῖς καὶ ἀπεράντους οὐκ ἔγραψαν λόγους, τὰ δʼ Ἐρασιστράτεια βιβλία παμπόλλους ἔχει τοὺς τοιούτους. τάχʼ ἂν οὖν ἤδη τις θαυμάζοι καὶ διαποροίη, τί παθὼν ὁ Ἐρασίστρατος εἰς τοσοῦτον τῶν Ἱπποκράτους δογμάτων ἀπετράπετο καὶ διὰ τί τῶν ἐν ἥπατι πόρων τῶν χοληδόχων, ἅλις γὰρ ἤδη νεφρῶν, ἀφελόμενος τὴν ἑλκτικὴν δύναμιν ἐπίκαιρον αἰτιᾶται θέσιν καὶ στομάτων στενότητα καὶ χώραν τινὰ κοινήν, εἰς ἣν παράγουσι μὲν αἱ ἀπὸ τῶν πυλῶν τὸ ἀκάθαρτον αἷμα, μεταλαμβάνουσι δὲ πρότεροι μὲν οἱ πόροι τὴν χολήν, δεύτεραι δʼ αἱ ἀπὸ τῆς κοίλης φλεβὸς τὸ καθαρὸν αἷμα. πρὸς γὰρ τῷ μηδὲν ἂν βλαβῆναι τὴν ὁλκὴν εἰπὼν ἄλλων μυρίων ἔμελλεν ἀμφισβητουμένων ἀπαλλάξεσθαι λόγων.

[¶13] 5. At the actual moment, however, the Erasistrateans are engaged in a considerable battle, not only with others but also amongst themselves, and so they cannot explain the passage from the first book of the “General Principles,” in which Erasistratus says, “Since there are two kinds of vessels opening at the same place, the one kind extending to the gall-bladder and the other to the vena cava, the result is that, of the nutriment carried up from the alimentary canal, that part which fits both kinds of stomata is received into both kinds of vessels, some being carried into the gall-bladder, and the rest passing over into the vena cava.” For it is difficult to say what we are to understand by the words “opening at the same place” which are written at the beginning of this passage. Either they mean there is a junction between the termination of the vein which is on the concave surface of the liver and two other vascular terminations (that of the vessel on the convex surface of the liver and that of the bile-duct), or, if not, then we must suppose that there is, as it were, a common space for all three vessels, which becomes filled from the lower vein, and empties itself both into the bile-duct and into the branches of the vena cava. Now, there are many difficulties in both of these explanations, but if I were to state them all, I should find myself inadvertently writing an exposition of the teaching of Erasistratus, instead of carrying out my original undertaking. There is, however, one difficulty common to both these explanations, namely, that the whole of the blood does not become purified. For it ought to fall into the bile-duct as into a kind of sieve, instead of going (running, in fact, rapidly) past it, into the larger stoma, by virtue of the impulse of anadosis. Are these, then, the only inevitable difficulties in which the argument of Erasistratus becomes involved through his disinclination to make any use of the attractive faculty, or is it that the difficulty is greatest here, and also so obvious that even a child could not avoid seeing it?

> Greek: 5. ὡς νῦν γε πόλεμος οὐ σμικρός ἐστι τοῖς Ἐρασιστρατείοις οὐ πρὸς τοὺς ἄλλους μόνον ἀλλὰ καὶ πρὸς ἀλλήλους, οὐκ ἔχουσιν, ὅπως ἐξηγήσωνται τὴν ἐκ τοῦ πρώτου τῶν καθόλου λόγων λέξιν, ἐν ᾗ φησιν· "Εἰς τὸ αὐτὸ δʼ ἀνεστομωμένων ἑτέρων δύο ἀγγείων τῶν τʼ ἐπὶ τὴν χοληδόχον τεινόντων καὶ τῶν ἐπὶ τὴν κοίλην φλέβα συμβαίνει τῆς ἀναφερομένης ἐκ τῆς κοιλίας τροφῆς τὰ ἐναρμόζοντα ἑκατέροις τῶν στομάτων εἰς ἑκάτερα τῶν ἀγγείων μεταλαμβάνεσθαι καὶ τὰ μὲν ἐπὶ τὴν χοληδόχον φέρεσθαι, τὰ δʼ ἐπὶ τὴν κοίλην φλέβα περαιοῦσθαι." τὸ γὰρ "εἰς τὸ αὐτὸ ἀνεστομωμένων," ὃ κατʼ ἀρχὰς τῆς λέξεως γέγραπται, τί ποτε χρὴ νοῆσαι, χαλεπὸν εἰπεῖν. ἤτοι γὰρ οὕτως εἰς ταὐτόν, ὥστε τῷ τῆς ἐν τοῖς σιμοῖς φλεβὸς πέρατι συνάπτειν δύο ἕτερα πέρατα, τό τʼ ἐν τοῖς κυρτοῖς καὶ τὸ τοῦ χοληδόχου πόρου, ἤ, εἰ μὴ οὕτω, χώραν τινὰ κοινὴν ἐπινοῆσαι χρὴ τῶν τριῶν ἀγγείων οἷον δεξαμενήν τινα, πληρουμένην μὲν ὑπὸ τῆς κάτω φλεβός, ἐκκενουμένην δʼ εἴς τε τοὺς χοληδόχους πόρους καὶ τὰς τῆς κοίλης ἀποσχίδας· καθʼ ἑκατέραν δὲ τῶν ἐξηγήσεων ἄτοπα πολλά, περὶ ὧν εἰ πάντων λέγοιμι, λάθοιμʼ ἂν ἐμαυτὸν ἐξηγήσεις Ἐρασιστράτου γράφων, οὐχ, ὅπερ ἐξ ἀρχῆς προὐθέμην, περαίνων. κοινὸν δʼ ἀμφοτέραις ταῖς ἐξηγήσεσιν ἄτοπον τὸ μὴ καθαίρεσθαι πᾶν τὸ αἷμα. χρὴ γὰρ ὡς εἰς ἠθμόν τινα τὸ χοληδόχον ἀγγεῖον ἐμπίπτειν αὐτό, οὐ παρέρχεσθαι καὶ παραρρεῖν ὠκέως εἰς τὸ μεῖζον στόμα τῇ Ῥύμῃ τῆς ἀναδόσεως φερόμενον. ἆρʼ οὖν ἐν τούτοις μόνον ἀπορίαις ἀφύκτοις ὁ Ἐρασιστράτου λόγος ἐνέχεται μὴ βουληθέντος χρήσασθαι ταῖς ἑλκτικαῖς δυνάμεσιν εἰς μηδέν, ἢ σφοδρότατα μὲν ἐν τούτοις καὶ σαφῶς οὕτως, ὡς ἂν μηδὲ παῖδα λαθεῖν;

[¶14] 6. And if one looks carefully into the matter one will find that even Erasistratus' reasoning on the subject of nutrition, which he takes up in the second book of his “General Principles,” fails to escape this same difficulty. For, having conceded one premise to the principle that matter tends to fill a vacuum, as we previously showed, he was only able to draw a conclusion in the case of the veins and their contained blood. That is to say, when blood is running away through the stomata of the veins, and is being dispersed, then, since an absolutely empty space cannot result, and the veins cannot collapse (for this was what he overlooked), it was therefore shown to be necessary that the that the adjoining quantum of fluid should flow in and fill the place of the fluid evacuated. It is in this way that we may suppose the veins to be nourished; they get the benefit of the blood which they contain. But how about the nerves? For they do not also contain blood. One might obviously say that they draw their supply from the veins. But Erasistratus will not have it so. What further contrivance, then, does he suppose? He says that a nerve has within itself veins and arteries, like a rope woven by Nature out of three different strands. By means of this hypothesis he imagined that his theory would escape from the idea of attraction. For if the nerve contain within itself a blood-vessel it will no longer need the adventitious flow of other blood from the real vein lying adjacent;

> Greek: 6. εἰ δʼ ἐπισκοποῖτό τις ἐπιμελῶς, οὐδʼ ὁ περὶ θρέψεως αὐτοῦ λόγος, ὃν ἐν τῷ δευτέρῳ τῶν καθόλου λόγων διεξέρχεται, τὰς αὐτὰς ἀπορίας ἐκφεύγει. τῇ γὰρ πρὸς τὸ κενούμενον ἀκολουθίᾳ συγχωρηθέντος ἑνὸς λήμματος, ὡς πρόσθεν ἐδείκνυμεν, ἐπέραινέ τι περὶ φλεβῶν μόνων καὶ τοῦ κατʼ αὐτὰς αἵματος. ἐκρέοντος γάρ τινος κατὰ τὰ στόματʼ αὐτῶν καὶ διαφορουμένου καὶ μήτʼ ἀθρόως τόπου κενοῦ δυναμένου γενέσθαι μήτε τῶν φλεβῶν συμπεσεῖν, τοῦτο γὰρ ἦν τὸ παραλειπόμενον, ἀναγκαῖον ἦν ἕπεσθαι τὸ συνεχὲς ἀναπληροῦν τοῦ κενου μένου τὴν βάσιν. αἱ μὲν δὴ φλέβες ἡμῖν οὕτω θρέψονται τοῦ περιεχομένου κατʼ αὐτὰς αἵματος ἀπολαύουσαι· τὰ δὲ νεῦρα πῶς; οὐ γὰρ δὴ κἀν τούτοις ἐστὶν αἷμα. πρόχειρον μὲν γὰρ ἦν εἰπεῖν, ἕλκοντα παρὰ τῶν φλεβῶν· ἀλλʼ οὐ βούλεται. τί ποτʼ οὖν κἀνταῦθα ἐπιτεχνᾶται; φλέβας ἔχειν ἐν ἑαυτῷ καὶ ἀρτηρίας τὸ νεῦρον ὥσπερ τινὰ σειρὰν ἐκ τριῶν ἱμάντων διαφερόντων τῇ φύσει πεπλεγμένην. ὠήθη γὰρ ἐκ ταύτης τῆς ὑποθέσεως ἐκφεύξεσθαι τῷ λόγῳ τὴν ὁλκήν· οὐ γὰρ ἂν ἔτι δεήσεσθαι τὸ νεῦρον ἐν ἑαυτῷ περιέχον αἵματος ἀγγεῖον ἐπιρρύτου τινὸς ἔξωθεν ἐκ τῆς παρακειμένης φλεβὸς τῆς ἀληθινῆς αἵματος ἑτέρου, ἀλλʼ ἱκανὸν αὐτῷ πρὸς τὴν θρέψιν ἔσεσθαι τὸ κατεψευσμένον ἀγγεῖον ἐκεῖνο τὸ λόγῳ θεωρητόν.

[¶15] this fictitious vessel, perceptible only in theory, will suffice it for nourishment. But this, again, is succeeded by another similar difficulty. For this small vessel will nourish itself, but it will not be able to nourish this adjacent simple nerve or artery, unless these possess some innate proclivity for attracting nutriment. For how could the nerve, being simple, attract its nourishment, as do the composite veins, by virtue of the tendency of a vacuum to become refilled? For, although according to Erasistratus, it contains within itself a cavity of sorts, this is not occupied with blood, but with psychic pneuma, and we are required to imagine the nutriment introduced, not into this cavity, but into the vessel containing it, whether it needs merely to be nourished, or to grow as well. How, then, are we to imagine it introduced? For this simple vessel [i.e.. nerve] is so small — as are also the other two — that if you prick it at any part with the finest needle you will tear the whole three of them at once. Thus there could never be in it a perceptible space entirely empty.

> Greek: ἀλλὰ κἀνταῦθα πάλιν αὐτὸν ὁμοία τις ἀπορία διεδέξατο. τουτὶ γὰρ τὸ σμικρὸν ἀγγεῖον ἑαυτὸ μὲν θρέψει, τὸ παρακείμενον μέντοι νεῦρον ἐκεῖνο τὸ ἁπλοῦν ἢ τὴν ἀρτηρίαν οὐχ οἷόν τʼ ἔσται τρέφειν ἄνευ τοῦ σύμφυτόν τινʼ ὑπάρχειν αὐτοῖς ὁλκὴν τῆς τροφῆς. τῇ μὲν γὰρ πρὸς τὸ κενούμενον ἀκολουθίᾳ πῶς ἂν ἔτι δύναιτο τὴν τροφὴν ἐπισπᾶσθαι τὸ ἁπλοῦν νεῦρον, ὥσπερ αἱ φλέβες αἱ σύνθετοι; κοιλότης μὲν γάρ τίς ἐστιν ἐν αὐτῷ κατʼ αὐτόν, ἀλλʼ οὐχ αἵματος αὕτη γʼ ἀλλὰ πνεύματος ψυχικοῦ μεστή. δεόμεθα δʼ ἡμεῖς οὐκ εἰς τὴν κοιλότητα ταύτην εἰσάγειν τῷ λόγῳ τὴν τροφὴν ἀλλʼ εἰς τὸ περιέχον αὐτὴν ἀγγεῖον, εἴτʼ οὖν τρέφεσθαι μόνον εἴτε καὶ αὔξεσθαι δέοιτο. πῶς οὖν εἰσάξομεν; οὕτω γάρ ἐστι σμικρὸν ἐκεῖνο τὸ ἁπλοῦν ἀγγεῖον καὶ μέντοι καὶ τῶν ἄλλων ἑκάτερον, ὥστʼ, εἰ τῇ λεπτοτάτῃ βελόνῃ νύξειάς τι μέρος, ἅμα διαιρήσεις τὰ τρία. τόπος οὖν αἰσθητὸς ἀθρόως κενὸς οὐκ ἄν ποτʼ ἐν αὐτῷ γένοιτο· λόγῳ δὲ θεωρητὸς τόπος κενούμενος οὐκ ἦν ἀναγκαστικὸς τῆς τοῦ συνεχοῦς ἀκολουθίας.