---
title: "On the Natural Faculties · Περὶ φυσικῶν δυνάμεων"
author: "Galen"
translator: "Arthur John Brock"
languages: [grc, en]
shelf: "Classical Greek"
section: 3 of 9
url: https://scriptura.si/works/galen-on-the-natural-faculties/3/
cite: "Galen, tr. Arthur John Brock, On the Natural Faculties · Περὶ φυσικῶν δυνάμεων, section 3. Scriptura (scriptura.si), https://scriptura.si/works/galen-on-the-natural-faculties/3/"
---

# 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.

## 3. Book I · sections 14–17

Source: https://scriptura.si/works/galen-on-the-natural-faculties/3/ · cite a paragraph as https://scriptura.si/works/galen-on-the-natural-faculties/3/#p-N

[¶0] Then, again, when a small body becomes entangled with another small body, or when a body in motion becomes entangled with another also in motion, they do not rebound at once. For, further, there will of course be others which break in upon them from above, from below, from front and rear, from right and left, and which shake and agitate them and never let them rest. Moreover, we must perforce suppose that each of these small bodies has a large number of these hook-like extremities. For by one it attaches itself to its neighbours, by another — the topmost one — to the lodestone, and by the bottom one to the iron. For if it were attached to the stone above and not interlocked with the iron below, this would be of no use. Thus, the upper part of the superior extremity must hang from the lodestone, and the iron must be attached to the lower end of the inferior extremity; and, since they interlock with each other by their sides as well, they must, of course, have hooks there too. Keep in mind also, above everything, what small bodies these are which possess all these different kinds of outgrowths. Still more, remember how, in order that the second piece of iron may become attached to the first, the third to the second, and to that the fourth, these absurd little particles must both penetrate the passages in the first piece of iron and at the same time rebound from the piece coming next in the series, although this second piece is naturally in every way similar to the first.

> Greek: εἶτα μικρὸν μικρῷ, κινούμενον κινουμένῳ περιπλακὲν οὐκ εὐθὺς ἀποπάλλεται. καὶ γὰρ δὴ καὶ ἄλλʼ ἄττα πάντως αὐτοῖς, τὰ μὲν ἄνωθεν, τὰ δὲ κάτωθεν, καὶ τὰ μὲν ἔμπροσθεν, τὰ δʼ ὄπισθεν, τὰ δʼ ἐκ τῶν δεξιῶν, τὰ δʼ ἐκ τῶν ἀριστερῶν ἐκρηγνύμενα σείει τε καὶ βράττει καὶ μένειν οὐκ ἐᾷ. καὶ μέντοι καὶ πολλὰ χρὴ νοεῖν ἐξ ἀνάγκης ἕκαστον ἐκείνων τῶν σμικρῶν σωμάτων ἔχειν ἀγκιστρώδη πέρατα. διʼ ἑνὸς μὲν γὰρ ἀλλήλοις συνάπτεται, διʼ ἑτέρου δʼ ἑνὸς τοῦ μὲν ὑπερκειμένου τῇ λίθῳ, τοῦ δʼ ὑποκειμένου τῷ σιδήρῳ. εἰ γὰρ ἄνω μὲν ἐξαφθείη τῆς λίθου, κάτω δὲ τῷ σιδήρῳ μὴ συμπλακείη, πλέον οὐδέν. ὥστε τοῦ μὲν ὑπερκειμένου τὸ ἄνω μέρος ἐκκρέμασθαι χρὴ τῆς λίθου, τοῦ δʼ ὑποκειμένου τῷ κάτω πέρατι συνῆφθαι τὸν σίδηρον. ἐπεὶ δὲ κἀκ τῶν πλαγίων ἀλλήλοις περιπλέκεται, πάντως που κἀνταῦθα ἔχει τὰ ἄγκιστρα. καὶ μέμνησό μοι πρὸ πάντων, ὅπως ὄντα σμικρὰ τὰς τοιαύτας καὶ τοσαύτας ἀποφύσεις ἔχει. καὶ τούτου μᾶλλον ἔτι, πῶς, ἵνα τὸ δεύτερον σιδήριον συναφθῇ τῷ πρώτῳ καὶ τῷ δευτέρῳ τὸ τρίτον κἀκείνῳ τὸ τέταρτον, ἅμα μὲν διεξέρχεσθαι χρὴ τοὺς πόρους ταυτὶ τὰ σμικρὰ καὶ ληρώδη ψήγματα, ἅμα δʼ ἀποπάλλεσθαι τοῦ μετʼ αὐτὸ τεταγμένου, καίτοι κατὰ πᾶν ὁμοίου τὴν φύσιν ὑπάρχοντος.

[¶1] Such an hypothesis, once again, is certainly not lacking in audacity; in fact, to tell the truth, it is far more shameless than the previous ones; according to it, when five similar pieces of iron are arranged in a line, the particles of the lodestone which easily traverse the first piece of iron rebound from the second, and do not pass readily through it in the same way. Indeed, it is nonsense, whichever alternative is adopted. For, if they do rebound, how then do they pass through into the third piece? And if they do not rebound, how does the second piece become suspended to the first? For Epicurus himself looked on the rebound as the active agent in attraction.

> Greek: οὐδὲ γὰρ ἡ τοιαύτη πάλιν ὑπόθεσις ἄτολμος, ἀλλʼ, εἰ χρὴ τἀληθὲς εἰπεῖν, μακρῷ τῶν ἔμπροσθεν ἀναισχυντοτέρα, πέντε σιδηρίων ὁμοίων ἀλλήλοις ἐφεξῆς τεταγμένων διὰ τοῦ πρώτου διαδυόμενα Ῥᾳδίως τῆς λίθου τὰ μόρια κατὰ τὸ δὲύτερον ἀποπάλλεσθαι καὶ μὴ διὰ τούτου κατὰ τὸν αὐτὸν τρόπον ἑτοίμως διεξέρχεσθαι. καὶ μὴν ἑκατέρως ἄτοπον. εἰ μὲν γὰρ ἀποπάλλεται, πῶς εἰς τὸ τρίτον ὠκέως διεξέρχεται; εἰ δʼ οὐκ ἀποπάλλεται, πῶς κρεμάννυται τὸ δεύτερον ἐκ τοῦ πρώτου; τὴν γὰρ ἀπόπαλσιν αὐτὸς ὑπέθετο δημιουργὸν τῆς ὁλκῆς. ἀλλʼ, ὅπερ ἔφην, εἰς ἀδολεσχίαν ἀναγκαῖον ἐμπίπτειν, ἐπειδάν τις τοιούτοις ἀνδράσι διαλέγηται.

[¶2] But, as I have said, one is driven to talk nonsense whenever one gets into discussion with such men. Having, therefore, given a concise and summary statement of the matter, I wish to be done with it. For if one diligently familiarizes oneself with the writings of Asclepiades, one will see clearly their logical dependence on his first principles, but also their disagreement with observed facts. Thus, Epicurus, in his desire to adhere to the facts, cuts an awkward figure by aspiring to show that these agree with his principles, whereas Asclepiades safeguards the sequence of principles, but pays no attention to the obvious fact. Whoever, therefore, wishes to expose the absurdity of their hypotheses, must, if the argument be in answer to Asclepiades, keep in mind his disagreement with observed fact; or if in answer to Epicurus, his discordance with his principles. Almost all the other sects depending on similar principles are now entirely extinct, while these alone maintain a respectable existence still. Yet the tenets of Asclepiades have been unanswerably confuted by Menodotus the Empiricist, who draws his attention to their opposition to phenomena and to each other; and, again, those of Epicurus have been confuted by Asclepiades, who adhered always to logical sequence, about which Epicurus evidently cares little.

> Greek: σύντομον οὖν τινα καὶ κεφαλαιώδη λόγον εἰπὼν ἀπαλλάττεσθαι βούλομαι. τοῖς Ἀσκληπιάδου γράμμασιν εἴ τις ἐπιμελῶς ὁμιλήσειε, τήν τε πρὸς τὰς ἀρχὰς ἀκολουθίαν τῶν τοιούτων δογμάτων ἀκριβῶς ἂν ἐκμάθοι καὶ τὴν πρὸς τὰ φαινόμενα μάχην. ὁ μὲν οὖν Ἐπίκουρος τὰ φαινόμενα φυλάττειν βουλόμενος ἀσχημονεῖ φιλοτιμούμενος ἐπιδεικνύειν αὐτὰ ταῖς ἀρχαῖς ὁμολογοῦντα· ὁ δʼ Ἀσκληπιάδης τὸ μὲν ἀκόλουθον ταῖς ἀρχαῖς φυλάττει, τοῦ φαινομένου δʼ οὐδὲν αὐτῷ μέλει. ὅστις οὖν βούλεται τὴν ἀτοπίαν ἐξελέγχειν τῶν ὑποθέσεων, εἰ μὲν πρὸς Ἀσκληπιάδην ὁ λόγος αὐτῷ γίγνοιτο, τῆς πρὸς τὸ φαινόμενον ὑπομιμνησκέτω μάχης· εἰ δὲ πρὸς Ἐπίκουρον, τῆς πρὸς τὰς ἀρχὰς διαφωνίας. αἱ δʼ ἄλλαι σχεδὸν αἱρέσεις αἱ τῶν ὁμοίων ἀρχῶν ἐχόμεναι τελέως ἀπέσβησαν, αὗται δʼ ἔτι μόναι διαρκοῦσιν οὐκ ἀγεννῶς. καίτοι τὰ μὲν Ἀσκληπιάδου Μηόδοτος ὁ ἐμπειρικὸς ἀφύκτως ἐξελέγχει, τήν τε πρὸς τὰ φαινόμενα μάχην ὑπομιμνήσκων αὐτὸν καὶ τὴν πρὸς ἄλληλα· τὰ δʼ Ἐπικούρου πάλιν ὁ Ἀσκληπιάδης ἐχόμενος ἀεὶ τῆς ἀκολουθίας, ἧς ἐκεῖνος οὐ πάνυ τι φαίνεται φροντίζων.

[¶3] Now people of the present day do not begin by getting a clear comprehension of these sects, as well as of the better ones, thereafter devoting a long time to judging and testing the true and false in each of them; despite their ignorance, they style themselves, some “physicians” and others “philosophers.” No wonder, then, that they honour the false equally with the true. For everyone becomes like the first teacher that he comes across, without waiting to learn anything from anybody else. And there are some of them, who, even if they meet with more than one teacher, are yet so unintelligent and slow-witted that even by the time they have reached old age they are still incapable of understanding the steps of an argument.... In the old days such people used to be set to menial tasks.... What will be the end of it God knows!

> Greek: ἀλλʼ οἱ νῦν ἄνθρωποι, πρὶν καὶ ταύτας ἐκμαθεῖν τὰς αἱρέσεις καὶ τὰς ἄλλας τὰς βελτίους κἄπειτα χρόνῳ πολλῷ κρῖναί τε καὶ βασανίσαι τὸ καθʼ ἑκάστην αὐτῶν ἀληθές τε καὶ ψεῦδος, οἱ μὲν ἰατροὺς ἑαυτούς, οἱ δὲ φιλοσόφους ὀνομάζουσι μηδὲν εἰδότες. οὐδὲν οὖν θαυμαστὸν ἐπίσης τοῖς ἀληθέσι τὰ ψευδῆ τετιμῆσθαι. ὅτῳ γὰρ ἂν ἕκαστος πρώτῳ περιτύχῃ διδασκάλῳ, τοιοῦτος ἐγένετο, μὴ περιμείνας μηδὲν ἔτι παρʼ ἄλλου μαθεῖν. ἔνιοι δʼ αὐτῶν, εἰ καὶ πλείοσιν ἐντύχοιεν, ἀλλʼ οὕτω γʼ εἰσὶν ἀσύνετοί τε καὶ βραδεῖς τὴν διάνοιαν, ὥστε καὶ γεγηρακότες οὔπω συνιᾶσιν ἀκολουθίαν λόγου. πάλαι δὲ τοὺς τοιούτους ἐπὶ τὰς βαναύσους ἀπέλυον τέχνας. ἀλλὰ ταῦτα μὲν ἐς ὅ τι τελευτήσει θεὸς οἶδεν.

[¶4] Now, we usually refrain from arguing with people whose principles are wrong from the outset. Still, having been compelled by the natural course of events to enter into some kind of a discussion with them, we must add this further to what was said — that it is not only cathartic drugs which naturally attract their special qualities, but also those which remove thorns and the points of arrows such as sometimes become deeply embedded in the flesh. Those drugs also which draw out animal poisons or poisons applied to arrows all show the same faculty as does the lodestone. Thus, I myself have seen a thorn which was embedded in a young man's foot fail to come out when we exerted forcible traction with our fingers, and yet come away painlessly and rapidly on the application of a medicament. Yet even to this some people will object, asserting that when the inflammation is dispersed from the part the thorn comes away of itself, without being pulled out by anything. But these people seem, in the first place, to be unaware that there are certain drugs for drawing out inflammation and different ones for drawing out embedded substances; and surely if it was on the cessation of an inflammation that the abnormal matters were expelled, then all drugs which disperse inflammations ought ipso facto; to possess the power of extracting these substances as well.

> Greek: ἡμεῖς δʼ ἐπειδή, καίτοι φεύγοντες ἀντιλέγειν τοῖς ἐν αὐταῖς ταῖς ἀρχαῖς εὐθὺς ἐσφαλμένοις, ὅμως ἠναγκάσθημεν ὑπʼ αὐτῆς τῶν πραγμάτων τῆς ἀκολουθίας εἰπεῖν τινα καὶ διαλεχθῆναι πρὸς αὐτούς, ἔτι καὶ τοῦτο προσθήσομεν τοῖς εἰρημένοις, ὡς οὐ μόνον τὰ καθαίροντα φάρμακα πέφυκεν ἐπισπᾶσθαι τὰς οἰκείας ποιότητας ἀλλὰ καὶ τὰ τοὺς σκόλοπας ἀνάγοντα καὶ τὰς τῶν βελῶν ἀκίδας εἰς πολὺ βάθος σαρκὸς ἐμπεπαρμένας ἐνίοτε. καὶ μέντοι καὶ ὅσα τοὺς ἰοὺς τῶν θηρίων ἢ τοὺς ἐμπεφαρμαγμένους τοῖς βέλεσιν ἀνέλκει, καὶ ταῦτα τὴν αὐτὴν ταῖς ἡρακλείαις λίθοις ἐπιδείκνυται δύναμιν. ἔγωγʼ οὖν οἶδά ποτε καταπεπαρμένον ἐν ποδὶ νεανίσκου σκόλοπα τοῖς μὲν δακτύλοις ἕλκουσιν ἡμῖν βιαίως οὐκ ἀκολουθήσαντα, φαρμάκου δʼ ἐπιτεθέντος ἀλύπως τε καὶ διὰ ταχέων ἀνελθόντα. καίτοι καὶ πρὸς τοῦτό τινες ἀντιλέγουσι φάσκοντες, ὅταν ἡ φλεγμονὴ λυθῇ τοῦ μέρους, αὐτόματον ἐξιέναι τὸν σκόλοπα πρὸς οὐδενὸς ἀνελκόμενον. ἀλλʼ οὗτοί γε πρῶτον μὲν ἀγνοεῖν ἐοίκασιν, ὡς ἄλλα μέν ἐστι φλεγμονῆς, ἄλλα δὲ τῶν οὕτω καταπεπαρμένων ἑλκτικὰ φάρμακα· καίτοι γʼ εἴπερ ἀφλεγμάντων γενομένων ἐξεκρίνετο τὰ παρὰ φύσιν, ὅσα φλεγμονῆς ἐστι λυτικά, ταῦτʼ εὐθὺς ἂν ἦν κἀκείνων ἑλκτικά.

[¶5] And secondly, these people seem to be unaware of a still more surprising fact, namely, that not merely do certain medicaments draw out thorns and others poisons, but that of the latter there are some which attract the poison of the viper, others that of the sting-ray, and others that of some other animal; we can, in fact, plainly observe these poisons deposited on the medicaments. Here, then, we must praise Epicurus for the respect he shows towards obvious facts, but find fault with his views as to causation. For how can it be otherwise than extremely foolish to suppose that a thorn which we failed to remove by digital traction could be drawn out by these minute particles?

> Greek: δεύτερον δʼ, ὃ καὶ μᾶλλον ἄν τις θαυμάσειεν, ὡς οὐ μόνον ἄλλα μὲν τοὺς σκόλοπας, ἄλλα δὲ τοὺς ἰοὺς ἐξάγει φάρμακα, ἀλλὰ καὶ αὐτῶν τῶν τοὺς ἰοὺς ἑλκόντων τὰ μὲν τὸν τῆς ἐχίδνης, τὰ δὲ τὸν τῆς τρυγόνος, τὰ δʼ ἄλλου τινὸς ἐπισπᾶται καὶ σαφῶς ἔστιν ἰδεῖν τοῖς φαρμάκοις ἐπικειμένους αὐτούς. ἐνταῦθʼ οὖν Ἐπίκουρον μὲν ἐπαινεῖν χρὴ τῆς πρὸς τὸ φαινόμενον αἰδοῦς, μέμφεσθαι δὲ τὸν λόγον τῆς αἰτίας. ὃν γὰρ ἡμεῖς ἕλκοντες τοῖς δακτύλοις οὐκ ἀνηγάγομεν σκόλοπα, τοῦτον ὑπὸ τῶν σμικρῶν ἐκείνων ἀνέλκεσθαι ψηγμάτων, πῶς οὐ παντάπασιν ἄτοπον εἶναι χρὴ νομίζειν; ἆρʼ οὖν ἤδη πεπείσμεθα τῶν ὄντων ἑκάστῳ δύναμίν τινʼ ὑπάρχειν, ᾗ τὴν οἰκείαν ἕλκει ποιότητα, τὸ μὲν μᾶλλον, τὸ δʼ ἧττον;

[¶6] Have we now, therefore, convinced ourselves that everything which exists possesses a faculty by which it attracts its proper quality, and that some things do this more, and some less?

> Greek: ἢ καὶ τὸ τῶν πυρῶν ἔτι παράδειγμα προχειρισόμεθα τῷ λόγῳ; φανήσονται γὰρ οἶμαι καὶ τῶν γεωργῶν αὐτῶν ἀμαθέστεροι περὶ τὴν φύσιν οἱ μηδὲν ὅλως ὑπὸ μηδενὸς ἕλκεσθαι συγχωροῦντες·

[¶7] Or shall we also furnish our argument with the illustration afforded by corn? For those who refuse to admit that anything is attracted by anything else, will, I imagine, be here proved more ignorant regarding Nature than the very peasants. When, for my own part, I first learned of what happens, I was surprised, and felt anxious to see it with my own eyes. Afterwards, when experience also had confirmed its truth, I sought long among the various sects for an explanation, and, with the exception of that which gave the first place to attraction, I could find none which even approached plausibility, all the others being ridiculous and obviously quite untenable.

> Greek: ὡς ἔγωγε πρῶτον, μὲν ἀκούσας τὸ γιγνόμενον ἐθαύμασα καὶ αὐτὸς ἠβουλήθην αὐτόπτης αὐτοῦ καταστῆναι. μετὰ ταῦτα δέ, ὡς καὶ τὰ τῆς πείρας ὡμολόγει, τὴν αἰτίαν σκοπούμενος ἐν παμπόλλῳ χρόνῳ κατὰ πάσας τὰς αἱρέσεις οὐδεμίαν ἄλλην εὑρεῖν οἷός τʼ ἦν οὐδʼ ἄχρι τοῦ πιθανοῦ προϊοῦσαν ἀλλὰ καταγελάστους τε καὶ σαφῶς ἐξελεγχομένας τὰς ἄλλας ἁπάσας πλὴν τῆς τὴν ὁλκὴν πρεσβευούσης. ἔστι δὲ τὸ γιγνόμενον τοιόνδε.

[¶8] What happens, then, is the following. When our peasants are bringing corn from the country into the city in wagons, and wish to filch some away without being detected, they fill earthen jars with water and stand them among the corn; the corn then draws the moisture into itself through the jar and acquires additional bulk and weight, but the fact is never detected by the onlookers unless someone who knew about the trick before makes a more careful inspection. Yet, if you care to set down the same vessel in the very hot sun, you will find the daily loss to be very little indeed. Thus corn has a greater power than extreme solar heat of drawing to itself the moisture in its neighbourhood. Thus the theory that the water is carried towards the rarefied part of the air surrounding us (particularly when that is distinctly warm) is utter nonsense; for although it is much more rarefied there than it is amongst the corn, yet it does not take up a tenth part of the moisture which the corn does.

> Greek: κατακομίζοντες οἱ παρʼ ἡμῖν γεωργοὶ τοὺς ἐκ τῶν ἀγρῶν πυροὺς εἰς τὴν πόλιν ἐν ἁμάξαις τισίν, ὅταν ὑφελέσθαι βουληθῶσιν, ὥστε μὴ φωραθῆναι, κεράμιʼ ἄττα πληρώσαντες ὕδατος μέσοις αὐτοῖς ἐνιστᾶσιν. ἕλκοντες οὖν ἐκεῖνοι διὰ τοῦ κεραμίου τὸ ὑγρὸν εἰς αὑτοὺς ὄγκον μὲν καὶ βάρος προσκτῶνται, κατάδηλοι δʼ οὐ πάνυ γίγνονται τοῖς ὁρῶσιν, εἰ μή τις προπεπυσμένος ἤδη περιεργότερον ἐπισκοποῖτο. καίτοι γʼ εἰ βουληθείης ἐν ἡλίῳ καταθεῖναι πάνυ θερμῷ ταὐτὸν ἀγγεῖον, ἐλάχιστον παντελῶς εὑρήσεις τὸ δαπανώμενον ἐφʼ ἑκάστης ἡμέρας. οὕτως ἄρα καὶ τῆς ἡλιακῆς θερμασίας τῆς σφοδρᾶς ἰσχυροτέραν οἱ πυροὶ δύναμιν ἔχουσιν ἕλκειν εἰς ἑαυτοὺς τὴν πλησιάζουσαν ὑγρότητα. λῆρος οὖν ἐνταῦθα μακρὸς ἡ πρὸς τὸ λεπτομερὲς φορὰ τοῦ περιέχοντος ἡμᾶς ἀέρος καὶ μάλισθʼ ὅταν ἱκανῶς ᾖ θερμός, πολὺ μὲν ὑπάρχοντος ἢ κατὰ τοὺς πυροὺς λεπτομερεστέρου, δεχομένου δʼ οὐδὲ τὸ δέκατον μέρος τῆς εἰς ἐκείνους μεταλαμβανομένης ὑγρότητος.

[¶9] 15. Since, then, we have talked sufficient nonsense — not willingly, but because we were forced, as the proverb says, “to behave madly among madmen” — let us return again to the subject of urinary secretion. Here let us forget the absurdities of Asclepiades, and, in company with those who are persuaded that the urine does pass through the kidneys, let us consider what is the character of this function. For, most assuredly, either the urine is conveyed by its own motion to the kidneys, considering this the better course (as do we when we go off to market! ), or, if this be impossible, then some other reason for its conveyance must be found. What, then, is this? If we are not going to grant the kidneys a faculty for attracting this particular quality, as Hippocrates held, we shall discover no other reason. For, surely everyone sees that either the kidneys must attract the urine, or the veins must propel it — if, that is, it does not move of itself. But if the veins did exert a propulsive action when they contract, they would squeeze out into the kidneys not merely the urine, but along with it the whole of the blood which they contain. And if this is impossible, as we shall show, the remaining explanation is that the kidneys do exert traction. And how is propulsion by the veins impossible? The situation of the kidneys is against it. They do not occupy a position beneath the hollow vein [vena cava] as does the sieve-like [ethmoid] passage in the nose and palate in relation to the surplus matter from the brain; they are situated on both sides of it. Besides, if the kidneys are like sieves, and readily let the thinner serous [whey-like] portion through, and keep out the thicker portion, then the whole of the blood contained in the vena cava must go to them, just as the whole of the wine is thrown into the filters. Further, the example of milk being made into cheese will show clearly what I mean. For this, too, although it is all thrown into the wicker strainers, does not all percolate through; such part of it as is too fine in proportion to the width of the meshes passes downwards, and this is called whey [serum]; the remaining thick portion which is destined to become cheese cannot get down, since the pores of the strainers will not admit it. Thus it is that, if the blood-serum has similarly to percolate through the kidneys, the whole of the blood must come to them, and not merely one part of it. What, then, is the appearance as found on dissection? One division of the vena cava is carried upwards to the heart, and the other mounts upon the spine and extends along its whole length as far as the legs; thus one division does not even come near the kidneys, while the other approaches them but is certainly not inserted into them. Now, if the blood were destined to be purified by them as if they were sieves, the whole of it would have to fall into them, the thin part being and the thick part retained above. But, as a matter of fact, this is not so. For the kidneys lie on either side of the vena cava. They therefore do not act like sieves, filtering fluid sent to them by the vena cava, and themselves contributing no force. They obviously exert traction; for this is the only remaining alternative. How, then, do they exert this traction? If, as Epicurus thinks, all attraction takes place by virtue of the rebounds and entanglements of atoms, it would be certainly better to maintain that the kidneys have no attractive action at all; for his theory, when examined, would be found as it stands to be much more ridiculous even than the theory of the lodestone, mentioned a little while ago. Attraction occurs in the way that Hippocrates laid down; this will be stated more clearly as the discussion proceeds; for the present our task is not to demonstrate this, but to point out that no other cause of the secretion of urine can be given except that of attraction by the kidneys, and that this attraction does not take place in the way imagined by people who do not allow Nature a faculty of her own. For if it be granted that there is any attractive faculty at all in those things which are governed by Nature, a person who attempted to say anything else about the absorption of nutriment would be considered a fool.

> Greek: 15. ἐπεὶ δʼ ἱκανῶς ἠδολεσχήσαμεν οὐχ ἑκόντες, ἀλλʼ, ὡς ἡ παροιμία φησί, μαινομένοις ἀναγκασθέντες συμμανῆναι, πάλιν ἐπὶ τὴν τῶν οὔρων ἐπανέλθωμεν διάκρισιν, ἐν ᾗ τῶν μὲν Ἀσκληπιάδου λήρων ἐπιλαθώμεθα, μετὰ δὲ τῶν πεπεισμένων διηθεῖσθαι τὰ οὖρα διὰ τῶν νεφρῶν, τίς ὁ τρόπος τῆς ἐνεργείας ἐστίν, ἐπισκεψώμεθα· πάντως γὰρ ἢ ἐξ αὑτῶν ἐπὶ τοὺς νεφροὺς φέρεται τὰ οὖρα τοῦτο βέλτιον εἶναι νομίζοντα, καθάπερ ἡμεῖς, ὁπόταν εἰς τὴν ἀγορὰν ἀπίωμεν· ἤ, εἰ τοῦτʼ ἀδύνατον, ἕτερόν τι χρὴ τῆς φορᾶς αὐτῶν ἐξευρεῖν αἴτιον. τί δὴ τοῦτʼ ἔστιν; εἰ γὰρ μὴ τοῖς νεφροῖς δώσομέν τινα δύναμιν ἑλκτικὴν τῆς τοιαύτης ποιότητος, ὡς Ἱπποκράτης ἐνόμιζεν, οὐδὲν ἕτερον ἐξευρήσομεν. ὅτι μὲν γὰρ ἤτοι τούτους ἕλκειν αὐτὸ προσῆκεν ἢ τὰς φλέβας πέμπειν, εἴπερ γε μὴ ἐξ ἑαυτοῦ φέρεται, παντί που δῆλον. ἀλλʼ εἰ μὲν αἱ φλέβες περιστελλόμεναι προωθοῖεν, οὐκ ἐκεῖνο μόνον, ἀλλὰ σὺν αὐτῷ καὶ τὸ πᾶν αἷμα τὸ περιεχόμενον ἐν ἑαυταῖς εἰς τοὺς νεφροὺς ἐκθλίψουσιν· εἰ δὲ τοῦτʼ ἀδύνατον, ὡς δείξομεν, λείπεται τοὺς νεφροὺς ἕλκειν. πῶς οὖν ἀδύνατον τοῦτο; τῶν νεφρῶν ἡ θέσις ἀντιβαίνει. οὐ γὰρ δὴ οὕτω γʼ ὑπόκεινται τῇ κοίλῃ φλεβὶ καθάπερ τοῖς ἐξ ἐγκεφάλου περιττώμασιν ἔν τε τῇ Ῥινὶ καὶ κατὰ τὴν ὑπερῴαν οἱ τοῖς ἠθμοῖς ὅμοιοι πόροι, ἀλλʼ ἑκατέρωθεν αὐτῇ παράκεινται. καὶ μήν, εἴπερ ὁμοίως τοῖς ἠθμοῖς ὅσον ἂν ᾖ λεπτότερον καὶ τελέως ὀρρῶδες, τοῦτο μὲν ἑτοίμως διαπέμπουσι, τὸ δὲ παχύτερον ἀποστέγουσιν, ἅπαν ἐπʼ αὐτοὺς ἰέναι χρὴ τὸ αἷμα τὸ περιεχόμενον ἐν τῇ κοίλῃ φλεβί, καθάπερ εἰς τοὺς τρυγητοὺς ὁ πᾶς οἶνος ἐμβάλλεται. καὶ μέν γε καὶ τὸ τοῦ γάλακτος τοῦ τυρουμένου παράδειγμα σαφῶς ἄν, ὃ βούλομαι λέγειν, ἐνδείξαιτο. καὶ γὰρ καὶ τοῦτο πᾶν ἐμβληθὲν εἰς τοὺς ταλάρους οὐ πᾶν διηθεῖται, ἀλλʼ ὅσον μὲν ἂν ᾖ λεπτότερον τῆς εὐρύτητος τῶν πλοκάμων, εἰς τὸ κάταντες φέρεται καὶ τοῦτο μὲν ὀρρὸς ἐπονομάζεται· τὸ λοιπὸν δὲ τὸ παχὺ τὸ μέλλον ἔσεσθαι τυρός, ὡς ἂν οὐ παραδεχομένων αὐτὸ τῶν ἐν τοῖς ταλάροις πόρων, οὐ διεκπίπτει κάτω. καὶ τοίνυν, εἴπερ οὕτω μέλλει διηθεῖσθαι τῶν νεφρῶν ὁ τοῦ αἵματος ὀρρός, ἅπαν ἐπʼ αὐτοὺς ἥκειν χρὴ τὸ αἷμα καὶ μὴ τὸ μὲν ναί, τὸ δʼ οὔ. Πῶς οὖν ἔχει τὸ φαινόμενον ἐκ τῆς ἀνατομῆς; τὸ μὲν ἕτερον μέρος τῆς κοίλης ἄνω πρὸς τὴν καρδίαν ἀναφέρεται, τὸ λοιπὸν δʼ ἐπιβαίνει τῇ Ῥάχει καθʼ ὅλης αὐτῆς ἐκτεινόμενον ἄχρι τῶν σκελῶν, ὥστε τὸ μὲν ἕτερον οὐδʼ ἐγγὺς ἀφικνεῖται τῶν νεφρῶν, τὸ λοιπὸν δὲ πλησιάζει μέν, οὐ μὴν εἰς αὐτούς γε καταφύεται. ἐχρῆν δʼ, εἴπερ ἔμελλεν ὡς διʼ ἠθμῶν αὐτῶν καθαρθήσεσθαι τὸ αἷμα, πᾶν ἐμπίπτειν εἰς αὐτοὺς κἄπειτα κάτω μὲν φέρεσθαι τὸ λεπτόν, ἴσχεσθαι δʼ ἄνω τὸ παχύ. νυνὶ δʼ οὐχ οὕτως ἔχει· πλάγιοι γὰρ ἑκατέρωθεν τῆς κοίλης φλεβὸς οἱ νεφροὶ κεῖνται. οὔκουν ὡς ἠθμοὶ διηθοῦσι, πεμπούσης μὲν ἐκείνης, αὐτοὶ δʼ οὐδεμίαν εἰσφερόμενοι δύναμιν, ἀλλʼ ἕλκουσι δηλονότι· τοῦτο γὰρ ἔτι λείπεται. πῶς οὖν ἕλκουσιν; εἰ μέν, ὡς Ἐπίκουρος οἴεται τὰς ὁλκὰς ἁπάσας γίγνεσθαι κατὰ τὰς τῶν ἀτόμων ἀποπάλσεις τε καὶ περιπλοκάς, ἄμεινον ἦν ὄντως εἰπεῖν αὐτοὺς μηδʼ ἕλκειν ὅλως· πολὺ γὰρ ἂν οὕτω γε τῶν ἐπὶ τῆς ἡρακλείας λίθου μικρῷ πρόσθεν εἰρημένων ὁ λόγος ἐξεταζόμενος εὑρεθείη γελοιότερος· ἀλλʼ ὡς Ἱπποκράτης ἠβούλετο. λεχθήσεται δὲ σαφέστερον ἐπὶ προήκοντι τῷ λόγῳ. νυνὶ γὰρ οὐ τοῦτο πρόκειται διδάσκειν, ἀλλʼ ὡς οὔτʼ ἄλλο τι δυνατὸν εἰπεῖν αἴτιον εἶναι τῆς τῶν οὔρων διακρίσεως πλὴν τῆς ὁλκῆς τῶν νεφρῶν οὔθʼ οὕτω γίγνεσθαι τὴν ὁλκήν, ὡς οἱ μἠδεμίαν οἰκείαν διδόντες τῇ φύσει δύναμιν οἴονται γίγνεσθαι. τούτου γὰρ ὁμολογηθέντος, ὡς ἔστιν ὅλως τις ἐν τοῖς ὑπὸ φύσεως διοικουμένοις δύναμις ἑλκτική, ληρώδης νομίζοιτʼ ἂν ὁ περὶ ἀναδόσεως τροφῆς ἄλλο τι λέγειν ἐπιχειρῶν.

[¶10] 16. Now, while Erasistratus for some reason replied at great length to certain other foolish doctrines, he entirely passed over the view held by Hippocrates, not even thinking it worth while to mention it, as he did in his work “On Deglutition”; in that work, as may be seen, he did go so far as at least to make mention of the word attraction, writing somewhat as follows:

> Greek: 16. Ἐρασίστρατος δʼ οὐκ οἶδʼ ὅπως ἑτέραις μέν τισι δόξαις εὐήθεσιν ἀντεῖπε διὰ μακρῶν, ὑπερέβη δὲ τελέως τὴν Ἱπποκράτους, οὐδʼ ἄχρι τοῦ μνημονεῦσαι μόνον αὐτῆς, ὡς ἐν τοῖς περὶ καταπόσεως ἐποίησεν, ἀξιώσας. ἐν ἐκείνοις μὲν γὰρ ἄχρι τοσούτου φαίνεται μνημονεύων, ὡς τοὔνομʼ εἰπεῖν τῆς ὁλκῆς μόνον ὧδέ πως γράφων·

[¶11] “Now, the stomach does not appear to exercise any attraction.” But when he is dealing with anadosis he does not mention the Hippocratic view even to the extent of a single syllable. Yet we should have been satisfied if he had even merely written this: “Hippocrates lies in saying 'The flesh attracts both from the stomach and from without,' for it cannot attract either from the stomach or from without.” Or if he had thought it worth while to state that Hippocrates was wrong in criticizing the weakness of the neck of the uterus, “seeing that the orifice of the uterus has no power of attracting semen,” or if he [Erasistratus] had thought proper to write any other similar opinion, then we in our turn would have defended ourselves in the following terms:

> Greek: "Ὁλκὴ μὲν οὖν τῆς κοιλίας οὐδεμία φαίνεται εἶναι"· περὶ δὲ τῆς ἀναδόσεως τὸν λόγον ποιούμενος οὐδʼ ἄχρι συλλαβῆς μιᾶς ἐμνημόνευσε τῆς Ἱπποκρατείου δόξης. καίτοι γʼ ἐπήρκεσεν ἂν ἡμῖν, εἰ καὶ τοῦτʼ ἔγραψε μόνον, ὡς Ἱπποκράτης εἰπὼν "Σάρκες ὁλκοὶ καὶ ἐκ κοιλίης καὶ ἔξωθεν" ψεύδεται· οὔτε γὰρ ἐκ τῆς κοιλίας οὔτʼ ἔξωθεν ἕλκειν δύνανται. εἰ δὲ καὶ ὅτι μήτρας αἰτιώμενος ἄρρωστον αὐχένα κακῶς εἶπεν "Οὐ γὰρ δύναται αὐτέης ὁ στόμαχος εἰρύσαι τὴν γονήν," ἢ εἰ καί τι τοιοῦτον ἄλλο γράφειν ὁ Ἐρασίστρατος ἠξίωσε, τότʼ ἂν καὶ ἡμεῖς πρὸς αὐτὸν ἀπολογούμενοι εἴπομεν·

[¶12] “My good sir, do not run us down in this rhetorical fashion without some proof; state some definite objection to our view, in order that either you may convince us by a brilliant refutation of the ancient doctrine, or that, on the other hand, we may convert you from your ignorance.” Yet why do I say “rhetorical”? For we too are not to suppose that when certain rhetoricians pour ridicule upon that which they are quite incapable of refuting, without any attempt at argument, their words are really thereby constituted rhetoric. For rhetoric proceeds by persuasive reasoning; words without reasoning are buffoonery rather than rhetoric. Therefore, the reply of Erasistratus in his treatise “On Deglutition” was neither rhetoric nor logic. For what is it that he says? “Now, the stomach does not appear to exercise any traction.” Let us testify against him in return, and set our argument beside his in the same form. Now, there appears to be no peristalsis of the gullet. “And how does this appear?” one of his adherents may perchance ask. “For is it not indicative of peristalsis that always when the upper parts of the gullet contract the lower parts dilate?” Again, then, we say, “And in what way does the attraction of the stomach not appear? For is it not indicative of attraction that always when the lower parts of the gullet dilate the upper parts contract?” Now, if he would but be sensible and recognize that this phenomenon is not more indicative of the one than of the other view, but that it applies equally to both, we should then show him without further delay the proper way to the discovery of truth.

> Greek: ὦ γενναῖε, μὴ Ῥητορικῶς ἡμῶν κατάτρεχε χωρὶς ἀποδείξεως, ἀλλʼ εἰπέ τινα κατηγορίαν τοῦ δόγματος, ἵνʼ ἢ πεισθῶμέν σοι ὡς καλῶς ἐξέλεγχοντι τὸν παλαιὸν λόγον ἢ μεταπείσωμεν ὡς ἀγνοοῦντα. καίτοι τί λέγω Ῥητορικῶς; μὴ γάρ, ἐπειδή τινες τῶν Ῥητόρων, ἃ μάλιστʼ ἀδυνατοῦσι διαλύεσθαι, ταῦτα διαγελάσαντες οὐδʼ ἐπιχειροῦσιν ἀντιλέγειν, ἤδη που τοῦτο καὶ ἡμεῖς ἡγώμεθʼ εἶναι τὸ Ῥητορικῶς· τὸ γὰρ διὰ λόγου πιθανοῦ ἐστι τὸ Ῥητορικῶς, τὸ δʼ ἄνευ λόγου βωμολοχικόν, οὐ Ῥητορικόν. οὔκουν οὔτε Ῥητορικῶς οὔτε διαλεκτικῶς ἀντεῖπεν ὁ Ἐρασίστρατος ἐν τῷ περὶ τῆς καταπόσεως λόγῳ. τί γάρ φησιν; "Ὁλκὴ μὲν οὖν τῆς κοιλίας οὐδεμία φαίνεται εἶναι." πάλιν οὖν αὐτῷ παρʼ ἡμῶν ἀντιμαρτυρῶν ὁ αὐτὸς λόγος ἀντιπαραβαλλέσθω· περιστολὴ μὲν οὖν τοῦ στομάχου οὐδεμία φαίνεται εἶναι. καὶ πῶς οὐ φαίνεται; τάχʼ ἂν ἴσως εἴποι τις τῶν ἀπʼ αὐτοῦ· τὸ γὰρ ἀεὶ τῶν ἄνωθεν αὐτοῦ μερῶν συστελλομένων διαστέλλεσθαι τὰ κάτω πῶς οὐκ ἔστι τῆς περιστολῆς ἐνδεικτικόν; αὖθις οὖν ἡμεῖς, καὶ πῶς οὐ φαίνεται, φήσομεν, ἡ τῆς κοιλίας ὁλκή; τὸ γὰρ ἀεὶ τῶν κάτωθεν μερῶν τοῦ στομάχου διαστελλομένων συστέλλεσθαι τὰ ἄνω πῶς οὐκ ἔστι τῆς ὁλκῆς ἐνδεικτικόν; εἰ δὲ σωφρονήσειέ ποτε καὶ γνοίη τὸ φαινόμενον τοῦτο μηδὲν μᾶλλον τῆς ἑτέρας τῶν δοξῶν ὑπάρχειν ἐνδεικτικὸν ἀλλʼ ἀμφοτέρων εἶναι κοινόν, οὕτως ἂν ἤδη δείξαιμεν αὐτῷ τὴν ὀρθὴν ὁδὸν τῆς τοῦ ἀληθοῦς εὑρέσεως.

[¶13] We will, however, speak about the stomach again. And the dispersal of nutriment [anadosis] need not make us have recourse to the theory regarding the natural tendency of a vacuum to become refilled, when once we have granted the attractive faculty of the kidneys. Now, although Erasistratus knew that this faculty most certainly existed, he neither mentioned it nor denied it, nor did he make any statement as to his views on the secretion of urine.

> Greek: ἀλλὰ περὶ μὲν τῆς κοιλίας αὖθις. ἡ δὲ τῆς τροφῆς ἀνάδοσις οὐδὲν δεῖται τῆς πρὸς τὸ κενούμενον ἀκολουθίας ἅπαξ γε τῆς ἑλκτικῆς δυνάμεως ἐπὶ τῶν νεφρῶν ὡμολογημένης, ἣν καίτοι πάνυ σαφῶς ἀληθῆ γιγνώσκων ὑπάρχειν ὁ Ἐρασίστρατος οὔτʼ ἐμνημόνευσεν οὔτʼ ἀντεῖπεν οὔθʼ ὅλως ἀπεφήνατο, τίνʼ ἔχει δόξαν ὑπὲρ τῆς τῶν οὔρων διακρίσεως.

[¶14] Why did he give notice at the very beginning of his “General Principles” that he was going to speak about natural activities — firstly what they are, how they take place, and in what situations — and then, in the case of urinary secretion, declared that this took place through the kidneys, but left out its method of occurrence? It must, then, have been for no purpose that he told us how digestion occurs, or spends time upon the secretion of biliary superfluities; for in these cases also it would have been sufficient to have named the parts through which the function takes place, and to have omitted the method. On the contrary, in these cases he was able to tell us not merely through what organs, but also in what way it occurs — as he also did, I think, in the case of anadosis; for he was not satisfied with saying that this took place through the veins, but he also considered fully the method, which he held to be from the tendency of a vacuum to become refilled. Concerning the secretion of urine, however, he writes that this occurs through the kidneys, but does not add in what way it occurs. I do not think he could say that this was from the tendency of matter to fill a vacuum, for, if this were so, nobody would have ever died of retention of urine, since no more can flow into a vacuum than has run out. For, if no other factor comes into operation save only this tendency by which a vacuum becomes refilled, no more could ever flow in than had been evacuated. Nor, could he suggest any other plausible cause, such, for example, as the of nutriment by the stomach which occurs in the process of anadosis; this had been entirely disproved in the case of blood in the vena cava; it is excluded, not merely owing to the long distance, but also from the fact that the overlying heart, at each diastole, robs the vena cava by violence of a considerable quantity of blood.

> Greek: ἢ διὰ τί προειπὼν εὐθὺς κατʼ ἀρχὰς τῶν καθʼ ὅλου λόγων, ὡς ὑπὲρ τῶν φυσικῶν ἐνεργειῶν ἐρεῖ, πρῶτον τίνες τʼ εἰσὶ καὶ πῶς γίγνονται καὶ διὰ τίνων τόπων, ἐπὶ τῆς τῶν οὔρων διακρίσεως, ὅτι μὲν διὰ νεφρῶν, ἀπεφήνατο, τὸ δʼ ὅπως γίγνεται παρέλιπε; μάτην οὖν ἡμᾶς καὶ περὶ τῆς πέψεως ἐδίδαξεν, ὅπως γίγνεται, καὶ περὶ τῆς τοῦ χολώδους περιττώματος διακρίσεως κατατρίβει. ἤρκει γὰρ εἰπεῖν κἀνταῦθα τὰ μόρια, διʼ ὧν γίγνεται, τὸ δʼ ὅπως παραλιπεῖν. ἀλλὰ περὶ μὲν ἐκείνων εἶχε λέγειν, οὐ μόνον διʼ ὧν ὀργάνων ἀλλὰ καὶ καθʼ ὅντινα γίγνεται τρόπον, ὥσπερ οἶμαι καὶ περὶ τῆς ἀναδόσεως· οὐ γὰρ ἤρκεσεν εἰπεῖν αὐτῷ μόνον, ὅτι διὰ φλεβῶν, ἀλλὰ καὶ πῶς ἐπεξῆλθεν, ὅτι τῇ πρὸς τὸ κενούμενον ἀκολουθίᾳ· περὶ δὲ τῶν οὔρων τῆς διακρίσεως, ὅτι μὲν διὰ νεφρῶν γίγνεται, γράφει, τὸ δʼ ὅπως οὐκέτι προστίθησιν. οὐδὲ γὰρ οἶμαι τῇ πρὸς τὸ κενούμενον ἀκολουθίᾳ ἦν εἰπεῖν· οὕτω γὰρ ἂν οὐδεὶς ὑπʼ ἰσχουρίας ἀπέθανεν οὐδέποτε μὴ δυναμένου πλείονος ἐπιρρυῆναί ποτε παρὰ τὸ κενούμενον· ἄλλης γὰρ αἰτίας μηδεμιᾶς προστεθείσης, ἀλλὰ μόνης τῆς πρὸς τὸ κενούμενον ἀκολουθίας ποδηγούσης τὸ συνεχές, οὐκ ἐγχωρεῖ πλέον ἐπιρρυῆναί ποτε τοῦ κενουμένου. ἀλλʼ οὐδʼ ἄλλην τινὰ προσθεῖναι πιθανὴν αἰτίαν εἶχεν, ὡς ἐπὶ τῆς ἀναδόσεως τὴν ἔκθλιψιν τῆς γαστρός. ἀλλʼ αὕτη γʼ ἐπὶ τοῦ κατὰ τὴν κοίλην αἵματος ἀπωλώλει τελέως, οὐ τῷ μήκει μόνον τῆς ἀποστάσεως ἐκλυθεῖσα, ἀλλὰ καὶ τῷ τὴν καρδίαν ὑπερκειμένην ἐξαρπάζειν αὐτῆς σφοδρῶς καθʼ ἑκάστην διαστολὴν οὐκ ὀλίγον αἷμα.

[¶15] In relation to the lower part of the vena cava there would still remain, solitary and abandoned, the specious theory concerning the filling of a vacuum. This, however, is deprived of plausibility by the fact that people die of retention of urine, and also, no less, by the situation of the kidneys. For, if the whole of the blood were carried to the kidneys, one might properly maintain that it all undergoes purification there. But, as a matter of fact, the whole of it does not go to them, but only so much as can be contained in the veins going to the kidneys; this portion only, therefore, will be purified. Further, the thin serous part of this will pass through the kidneys as if through a sieve, while the thick sanguineous portion remaining in the veins will obstruct the blood flowing in from behind; this will first, therefore, have to run back to the vena cava, and so to empty the veins going to the kidneys; these veins will no longer be able to conduct a second quantity of unpurified blood to the kidneys — occupied as they are by the blood which had preceded, there is no passage left. What power have we, then, which will draw back the purified blood from the kidneys? And what power, in the next place, will bid this blood retire to the lower part of the vena cava, and will enjoin on another quantity coming from above not to proceed downwards before turning off into the kidneys?

> Greek: μόνη δή τις ἔτι καὶ πάντων ἔρημος ἀπελείπετο τῶν σοφισμάτων ἐν τοῖς κάτω τῆς κοίης ἡ πρὸς τὸ κενούμενον ἀκολουθία, διά τε τοὺς ἐπὶ ταῖς ἰσχουρίαις ἀποθνήσκοντας ἀπολωλεκυῖα τὴν πιθανότητα καὶ διὰ τὴν τῶν νεφρῶν θέσιν οὐδὲν ἧττον. εἰ μὲν γὰρ ἅπαν ἐπʼ αὐτοὺς ἐφέρετο τὸ αἷμα, δεόντως ἄν τις ἅπαν ἔφασκεν αὐτὸ καθαίρεσθαι. νυνὶ δέ, οὐ γὰρ ὅλον ἀλλὰ τοσοῦτον αὐτοῦ μέρος, ὅσον αἱ μέχρι νεφρῶν δέχονται φλέβες, ἐπʼ αὐτοὺς ἔρχεται, μόνον ἐκεῖνο καθαρθήσεται. καὶ τὸ μὲν ὀρρῶδες αὐτοῦ καὶ λεπτὸν οἷον διʼ ἠθμῶν τινων τῶν νεφρῶν διαδύσεται· τὸ δʼ αἱματῶδές τε καὶ παχὺ κατὰ τὰς φλέβας ὑπομένον ἐμποδὼν στήσεται τῷ κατόπιν ἐπιρρέοντι. παλινδρομεῖν οὖν αὐτὸ πρότερον ἐπὶ τὴν κοίλην ἀναγκαῖον καὶ κενὰς οὕτως ἐργάζεσθαι τὰς ἐπὶ τοὺς νεφροὺς ἰούσας φλέβας, αἳ δεύτερον οὐκέτι παρακομιοῦσιν ἐπʼ αὐτοὺς ἀκάθαρτον αἷμα· κατειληφότος γὰρ αὐτὰς τοῦ προτέρου πάροδος οὐδεμία λέλειπται. τίς οὖν ἡμῖν ἡ δύναμις ἀπάξει πάλιν ὀπίσω τῶν νεφρῶν τὸ καθαρὸν αἷμα; τίς δὲ τοῦτο μὲν διαδεξαμένη κελεύσει πάλιν πρὸς τὸ κάτω μέρος ἰέναι τῆς κοίλης, ἑτέρῳ δʼ ἄνωθεν ἐπιφερομένῳ προστάξει, πρὶν ἐπὶ τοὺς νεφροὺς ἀπελθεῖν, μὴ φέρεσθαι κάτω;

[¶16] Now Erasistratus realized that all these ideas were open to many objections, and he could only find one idea which held good in all respects — namely, that of attraction. Since, therefore, he did not wish either to get into difficulties or to mention the view of Hippocrates, he deemed it better to say nothing at all as to the manner in which secretion occurs.

> Greek: ταῦτʼ οὖν ἅπαντα συνιδὼν ὁ Ἐρασίστρατος ἀποριῶν μεστὰ καὶ μίαν μόνην δόξαν εὔπορον εὑρὼν ἐν ἅπασι τὴν τῆς ὁλκῆς, οὔτʼ ἀπορεῖσθαι βουλόμενος οὔτε τὴν Ἱπποκράτους ἐθέλων λέγειν ἄμεινον ὑπέλαβε σιωπητέον εἶναι περὶ τοῦ τρόπου τῆς διακρίσεως. ἀλλʼ εἰ κἀκεῖνος ἐσίγησεν, ἡμεῖς οὐ σιωπήσομεν·

[¶17] But even if he kept silence, I am not going to do so. For I know that if one passes over the Hippocratic view and makes some other pronouncement about the function of the kidneys, one cannot fall to make oneself utterly ridiculous. It was for this reason that Erasistratus kept silence and Asclepiades lied; they are like slaves who have had plenty to say in the early part of their career, and have managed by excessive rascality to escape many and frequent accusations, but who, later, when caught in the act of thieving, cannot find any excuse; the more modest one then keeps silence, as though thunderstruck, whilst the more shameless continues to hide the missing article beneath his arm and denies on oath that he has ever seen it. For it was in this way also that Asclepiades, when all subtle excuses had failed him and there was no longer any room for nonsense about “conveyance towards the rarefied part [of the air],” and when it was impossible without incurring the greatest derision to say that this superfluity [i.e.. the urine] is generated by the kidneys as is bile by the canals in the liver — he, then, I say, clearly lied when he swore that the urine does not reach the kidneys, and maintained that it passes, in the form of vapour, straight from the region of the vena cava, to collect in the bladder.

> Greek: ἴσμεν γάρ, ὡς οὐκ ἐνδέχεται παρελθόντα τὴν Ἱπποκράτειον δόξαν, εἶθʼ ἕτερόν τι περὶ νεφρῶν ἐνεργείας εἰπόντα μὴ οὐ καταγέλαστον εἶναι παντάπασι. διὰ τοῦτʼ Ἐρασίστρατος μὲν ἐσιώπησεν, Ἀσκληπιάδης δʼ ἐψεύσατο παραπλησίως οἰκέταις λάλοις μὲν τὰ πρόσθεν τοῦ βίου καὶ πολλὰ πολλάκις ἐγκλήματα διαλυσαμένοις ὑπὸ περιττῆς πανουργίας, ἐπʼ αὐτοφώρῳ δέ ποτε κατειλημμένοις, εἶτʼ οὐδὲν ἐξευρίσκουσι σόφισμα κἄπειτʼ ἐνταῦθα τοῦ μὲν αἰδημονεστέρου σιωπῶντος, οἷον ἀποπληξίᾳ τινὶ κατειλημμένου, τοῦ δʼ ἀναισχυντοτέρου κρύπτοντος μὲν ἔθʼ ὑπὸ μάλης τὸ ζητούμενον, ἐξομνυμένου δὲ καὶ μηδʼ ἑωρακέναι πώποτε φάσκοντος. οὕτω γάρ τοι καὶ ὁ Ἀσκληπιάδης ἐπιλειπόντων αὐτὸν τῶν τῆς πανουργίας σοφισμάτων καὶ μήτε τῆς πρὸς τὸ λεπτομερὲς φορᾶς ἐχούσης ἔτι χώραν ἐνταυθοῖ ληρεῖσθαι μήθʼ ὡς ὑπὸ τῶν νεφρῶν γεννᾶται τουτὶ τὸ περίττωμα, καθάπερ ὑπὸ τῶν ἐν ἥπατι πόρων ἡ χολή, δυνατὸν ὂν εἰπόντα μὴ οὐ μέγιστον ὀφλεῖν γέλωτα, ἐξόμνυταί τε καὶ ψεύδεται φανερῶς, οὐ διήκειν λέγων ἐπὶ τοὺς νεφροὺς τὸ οὖρον ἀλλʼ ἀτμοειδῶς εὐθὺς ἐκ τῶν κατὰ τὴν κοίλην μερῶν εἰς τὴν κύστιν ἀθροίζεσθαι.

[¶18] Like slaves, then, caught in the act of stealing, these two are quite bewildered, and while the one says nothing, the other indulges in shameless lying.

> Greek: οὗτοι μὲν οὖν τοῖς ἐπʼ αὐτοφώρῳ κατειλημμένοις οἰκέταις ὁμοίως ἐκπλαγέντες ὁ μὲν ἐσιώπησεν, ὁ δʼ ἀναισχύντως ψεύδεται.

[¶19] 17. Now such of the younger men as have dignified themselves with the names of these two authorities by taking the appellations “Erasistrateans” or “Asclepiadeans” are like the Davi and Getae — the slaves introduced by the excellent Menander into his comedies. As these slaves held that they had done nothing fine unless they had cheated their master three times, so also the men I am discussing have taken their time over the construction of impudent sophisms, the one party striving to prevent the lies of Asclepiades from ever being refuted, and the other saying stupidly what Erasistratus had the sense to keep silence about. But enough about the Asclepiadeans. The Erasistrateans, in attempting to say how the kidneys let the urine through, will do anything or suffer anything or try any shift in order to find some plausible explanation which does not demand the principle of attraction. Now those near the times of Erasistratus maintain that the parts above the kidneys receive pure blood, whilst the watery residue, being heavy, tends to run downwards; that this, after percolating through the kidneys themselves, is thus rendered serviceable, and is sent, as blood, to all the parts below the kidneys. For a certain period at least this view also found favour and flourished, and was held to be true; after a time, however, it became suspect to the Erasistrateans themselves, and at last they abandoned it. For apparently the following two points were assumed, neither of which is conceded by anyone, nor is even capable of being proved. The first is the heaviness of the serous fluid, which was said to be produced in the vena cava, and which did not exist, apparently, at the beginning, when this fluid was being carried up from the stomach to the liver. Why, then, did it not at once run downwards when it was in these situations? And if the watery fluid is so heavy, what plausibility can anyone find in the statement that it assists in the process of anadosis? In the second place there is this absurdity, that even if it be agreed that all the watery fluid does fall downwards, and only when it is in the vena cava, still it is difficult, or, rather, impossible, to say through what means it is going to fall into the kidneys, seeing that these are not situated below, but on either side of the vena cava, and that the vena cava is not inserted into them, but merely sends a branch into each of them, as it also does into all the other parts. What doctrine, then, took the place of this one when it was condemned? One which to me seems far more foolish than the first, although it also flourished at one time. For they say, that if oil be mixed with water and poured upon the ground, each will take a different route, the one flowing this way and the other that, and that, therefore, it is not surprising that the watery fluid runs into the kidneys, while the blood falls downwards along the vena cava. Now this doctrine also stands already condemned. For why, of the countless veins which spring from the vena cava, should blood flow into all the others, and the serous fluid be diverted to those going to the kidneys? They have not answered the question which was asked; they merely state what happens and imagine they have thereby assigned the reason. Once again, then (the third cup to the Saviour!), let us now speak of the worst doctrine of all, lately invented by Lycus of Macedonia, but which is popular owing to its novelty. This Lycus, then, maintains, as though uttering an oracle from the inner sanctuary, that urine is residual matter from the nutrition of the kidneys! Now, the amount of urine passed every day shows clearly that it is the whole of the fluid drunk which becomes urine, except for that which comes away with the dejections or passes off as sweat or insensible perspiration. This is most easily recognized in winter in those who are doing no work but are carousing, especially if the wine be thin and diffusible; these people rapidly pass almost the same quantity as they drink. And that even Erasistratus was aware of this is known to those who have read the first book of his “General Principles.” Thus Lycus is speaking neither good Erasistratism, nor good Asclepiadism, far less good Hippocratism. He is, therefore, as the saying is, like a white crow, which cannot mix with the genuine crows owing to its colour, nor with the pigeons owing to its size. For all this, however, he is not to be disregarded; he may, perhaps, be stating some wonderful truth, unknown to any of his predecessors. Now it is agreed that all parts which are undergoing nutrition produce a certain amount of residue, but it is neither agreed nor is it likely, that the kidneys alone, small bodies as they are, could hold four whole congii, and sometimes even more, of residual matter. For this surplus must necessarily be greater in quantity in each of the larger viscera; thus, for example, that of the lung, if it corresponds in amount to the size of the viscus, will obviously be many times more than that in the kidneys, and thus the whole of the thorax will become filled, and the animal will be at once suffocated. But if it be said that the residual matter is equal in amount in each of the other parts, where are the bladders, one may ask, through which it is excreted? For, if the kidneys produce in drinkers three and sometimes four congii of superfluous matter, that of each of the other viscera will be much more, and thus an enormous barrel will be needed to contain the waste products of them all. Yet one often urinates practically the same quantity as one has drunk, which would show that the whole of what one drinks goes to the kidneys. Thus the author of this third piece of trickery would appear to have achieved nothing, but to have been at once detected, and there still remains the original difficulty which was insoluble by Erasistratus and by all others except Hippocrates. I dwell purposely on this topic, knowing well that nobody else has anything to say about the function of the kidneys, but that either we must prove more foolish than the very butchers if we do not agree that the urine passes through the kidneys; or, if one acknowledges this, that then one cannot possibly give any other reason for the secretion than the principle of attraction. Now, if the movement of urine does not depend on the tendency of a vacuum to become refilled, it is clear that neither does that of the blood nor that of the bile; or if that of these latter does so, then so also does that of the former. For they must all be accomplished in one and the same way, even according to Erasistratus himself. This matter, however, will be discussed more fully in the book following this.

> Greek: 17. τῶν δὲ νεωτέρων ὅσοι τοῖς τούτων ὀνόμασιν ἑαυτοὺς ἐσέμνυναν Ἐρασιστρατείους τε καὶ Ἀσκληπιαδείους ἐπονομάσαντες, ὁμοίως τοῖς ὑπὸ τοῦ βελτίστου Μενάνδρου κατὰ τὰς κωμῳδίας εἰσαγομένοις οἰκέταις, Δάοις τέ τισι καὶ Γέταις, οὐδὲν ἡγουμένοις σφίσι πεπρᾶχθαι γενναῖον, εἰ μὴ τρὶς ἐξαπατήσειαν τὸν δεσπότην, οὕτω καὶ αὐτοὶ κατὰ πολλὴν σχολὴν ἀναίσχυντα σοφίσματα συνέθεσαν, οἱ μέν, ἵνα μηδʼ ὅλως ἐξελεγχθείη ποτʼ Ἀσκληπιάδης ψευδόμενος, οἱ δʼ, ἵνα κακῶς εἴπωσιν, ἃ καλῶς ἐσιώπησεν Ἐρασίστρατος. ἀλλὰ τῶν μὲν Ἀσκληπιαδείων ἅλις. οἱ δʼ Ἐρασιστράτειοι λέγειν ἐπιχειροῦντες, ὅπως οἱ νεφροὶ διηθοῦσι τὸ οὖρον, ἅπαντα δρῶσί τε καὶ πάσχουσι καὶ παντοῖοι γίγνονται πιθανὸν ἐξευρεῖν τι ζητοῦντες αἴτιον ὁλκῆς μὴ δεόμενον. οἱ μὲν δὴ πλησίον Ἐρασιστράτου τοῖς χρόνοις γενόμενοι τὰ μὲν ἄνω τῶν νεφρῶν μόρια καθαρὸν αἷμα λαμβάνειν φασί, τῷ δὲ βάρος ἔχειν τὸ ὑδατῶδες περίττωμα βρίθειν τε καὶ ὑπορρεῖν κάτω· διηθούμενον δʼ ἐνταῦθα κατὰ τοὺς νεφροὺς αὐτοὺς χρηστὸν οὕτω γενόμενον ἅπασι τοῖς κάτω τῶν νεφρῶν ἐπιπέμπεσθαι τὸ αἷμα. καὶ μέχρι γέ τινος εὐδοκίμησεν ἥδε ἡ δόξα καὶ ἤκμασε καὶ ἀληθὴς ἐνομίσθη· χρόνῳ δʼ ὕστερον καὶ αὐτοῖς τοῖς Ἐρασιστρατείοις ὕποπτος ἐφάνη καὶ τελευτῶντες ἀπέστησαν αὐτῆς. αἰτεῖσθαι γὰρ ἐδόκουν δύο ταῦτα μήτε συγχωρούμενα πρός τινος ἀλλʼ οὐδʼ ἀποδειχθῆναι δυνάμενα, πρῶτον μὲν τὸ βάρος τῆς ὀρρώδους ὑγρότητος ἐν τῇ κοίλῃ φλεβὶ γεννώενον, ὥσπερ οὐκ ἐξ ἀρχῆς ὑπάρχον, ὁπότʼ ἐκ τῆς κοιλίας εἰς ἧπαρ ἀνεφέρετο. τί δὴ οὖν οὐκ εὐθὺς ἐν ἐκείνοις τοῖς χωρίοις ὑπέρρει κάτω; πῶς δʼ ἄν τῳ δόξειεν εὐλόγως εἰρῆσθαι συντελεῖν εἰς τὴν ἀνάδοσιν ἡ ὑδατώδης ὑγρότης, εἴπερ οὕτως ἐστὶ βαρεῖα; δεύτερον δʼ ἄτοπον, ὅτι κἂν κάτω συγχωρηθῇ φέρεσθαι πᾶσα καὶ μὴ κατʼ ἄλλο χωρίον ἢ τὴν κοίλην φλέβα, τίνα τρόπον εἰς τοὺς νεφροὺς ἐμπεσεῖται, χαλεπόν, μᾶλλον δʼ ἀδύνατον εἰπεῖν, μήτʼ ἐν τοῖς κάτω μέρεσι κειμένων αὐτῶν τῆς φλεβὸς ἀλλʼ ἐκ τῶν πλαγίων μήτʼ ἐμφυομένης εἰς αὐτοὺς τῆς κοίλης ἀλλʼ ἀπόφυσίν τινα μόνον εἰς ἑκάτερον πεμπούσης, ὥσπερ καὶ εἰς τἆλλα πάντα μόρια. τίς οὖν ἡ διαδεξαμένη ταύτην δόξα καταγνωσθεῖσαν; ἐμοὶ μὲν ἠλιθιωτέρα μακρῷ φαίνεται τῆς προτέρας. ἤκμασε δʼ οὖν καὶ αὕτη ποτέ. φασὶ γάρ, εἰ κατὰ τῆς γῆς ἐκχυθείη μεμιγμένον ἔλαιον ὕδατι, διάφορον ἑκάτερον ὁδὸν βαδιεῖσθαι καὶ Ῥυήσεσθαι τὸ μὲν τῇδε, τὸ δὲ τῇδε. θαυμαστὸν οὖν οὐδὲν εἶναί φασιν, εἰ τὸ μὲν ὑδατῶδες ὑγρὸν εἰς τοὺς νεφροὺς Ῥεῖ, τὸ δʼ αἷμα διὰ τῆς κοίλης φέρεται κάτω. κατέγνωσται οὖν ἤδη καὶ ἥδε ἡ δόξα. διὰ τί γὰρ ἀπὸ τῆς κοίλης μυρίων ἐκπεφυκυιῶν φλεβῶν αἷμα μὲν εἰς τὰς ἄλλας ἁπάσας, ἡ δʼ ὀρρώδης ὑγρότης εἰς τὰς ἐπὶ τοὺς νεφροὺς φερομένας ἐκτρέπεται; τοῦτʼ αὐτὸ τὸ ζητούμενον οὐκ εἰρήκασιν, ἀλλὰ τὸ γιγνόμενον εἰπόντες μόνον οἴονται τὴν αἰτίαν ἀποδεδωκέναι. πάλιν οὖν, τὸ τρίτον τῷ σωτῆρι, τὴν χειρίστην ἁπασῶν δόξαν ἐξευρημένην νῦν ὑπὸ Λύκου τοῦ Μακεδόνος, εὐδοκιμοῦσαν δὲ διὰ τὸ καινὸν ἤδη λέγωμεν. ἀπεφήνατο γὰρ δὴ ὁ Λύκος οὗτος, ὥσπερ ἐξ ἀδύτου τινὸς χρησμὸν ἀποφθεγγόμενος, περίττωμα τῆς τῶν νεφρῶν θρέψεως εἶναι τὸ οὖρον. ὅτι μὲν οὖν αὐτὸ τὸ πινόμενον ἅπαν οὖρον γίγνεται, πλὴν εἴ τι μετὰ τῶν διαχωρημάτων ὑπῆλθεν ἢ εἰς ἱδρῶτας ἀπεχώρησεν ἢ εἰς τὴν ἄδηλον διαπνοήν, ἐναργῶς ἐνδείκνυται τὸ πλῆθος τῶν καθʼ ἑκάστην ἡμέραν οὐρουμένων. ἐν χειμῶνι δὲ μάλιστα μαθεῖν ἔστιν ἐπὶ τῶν ἀργούντων μέν, κωθωνιζομένων δέ, καὶ μάλιστʼ εἰ λεπτὸς ὁ οἶνος εἴη καὶ πόριμος. οὐροῦσι γὰρ οὗτοι διὰ ταχέων ὀλίγου δεῖν, ὅσονπερ καὶ πίνουσιν. ὅτι δὲ καὶ ὁ Ἐρασίστρατος οὕτως ἐγίγνωσκεν, οἱ τὸ πρῶτον ἀνεγνωκότες αὐτοῦ σύγγραμμα τῶν καθόλου λόγων ἐπίστανται. ὥσθʼ ὁ Λύκος οὔτʼ ἀληθῆ φαίνεται λέγων οὔτʼ Ἐρασιστράτεια, δῆλον δʼ ὡς οὐδʼ Ἀσκληπιάδεια, πολὺ δὲ μᾶλλον οὐδʼ Ἱπποκράτεια. λευκῷ τοίνυν κατὰ τὴν παροιμίαν ἔοικε κόρακι μήτʼ αὐτοῖς τοῖς κόραξιν ἀναμιχθῆναι δυναμένῳ διὰ τὴν χρόαν μήτε ταῖς περιστεραῖς διὰ τὸ μέγεθος, ἀλλʼ οὔτι που τούτου γʼ ἕνεκα παροπτέος· ἴσως γάρ τι λέγει θαυμαστόν, ὃ μηδεὶς τῶν ἔμπροσθεν ἔγνω. τὸ μὲν οὖν ἅπαντα τὰ τρεφόμενα μόρια ποιεῖν τι περίττωμα συγχωρούμενον, τὸ δὲ τοὺς νεφροὺς μόνους, οὕτω σμικρὰ σώματα, χόας ὅλους τέτταρας ἢ καὶ πλείους ἴσχειν ἐνίοτε περιττώματος οὔθʼ ὁμολογούμενον οὔτε λόγον ἔχον· τὸ γὰρ ἑκάστου τῶν μειζόνων σπλάγχνων περίττωμα πλεῖον ἀναγκαῖον ὑπάρχειν. οἷον αὐτίκα τὸ τοῦ πνεύμονος, εἴπερ ἀνάλογον τῷ μεγέθει τοῦ σπλάγχνου γίγνοιτο, πολλαπλάσιον ἔσται δήπου τοῦ κατὰ τοὺς νεφρούς, ὥσθʼ ὅλος μὲν ὁ θώραξ ἐμπλησθήσεται, πνιγήσεται δʼ αὐτίκα τὸ ζῷον. ἀλλʼ εἰ ἴσον φήσει τις γίγνεσθαι τὸ καθʼ ἕκαστον τῶν ἄλλων μορίων περίττωμα, διὰ ποίων κύστεων ἐκκρίνεται; εἰ γὰρ οἱ νεφροὶ τοῖς κωθωνιζομένοις τρεῖς ἢ τέτταρας ἐνίοτε χόας ποιοῦσι περιττώματος, ἑκάστου τῶν ἄλλων σπλάγχνων πολλῷ πλείους ἔσονται καὶ πίθου τινὸς οὕτω μεγίστου δεήσει τοῦ δεξομένου τὰ πάντων περιττώματα. καίτοι πολλάκις, ὅσον ἔπιέ τις, ὀλίγου δεῖν οὔρησεν ἅπαν, ὡς ἂν ἐπὶ τοὺς νεφροὺς φερομένου τοῦ πόματος ἅπαντος. ἔοικεν οὖν ὁ τὸ τρίτον ἐξαπατῶν οὗτος οὐδὲν ἀνύειν ἀλλʼ εὐθὺς γεγονέναι κατάφωρος καὶ μένειν ἔτι τὸ ἐξ ἀρχῆς ἄπορον Ἐρασιστράτῳ τε καὶ τοῖς ἄλλοις ἅπασι πλὴν Ἱπποκράτους. διατρίβω δʼ ἑκὼν ἐν τῷ τόπῳ σαφῶς εἰδώς, ὅτι μηδὲν εἰπεῖν ἔχει μηδεὶς ἄλλος περὶ τῆς τῶν νεφρῶν ἐνεργείας, ἀλλʼ ἀναγκαῖον ἢ τῶν μαγείρων ἀμαθεστέρους φαίνεσθαι μηδʼ ὅτι διηθεῖται διʼ αὐτῶν τὸ οὖρον ὁμολογοῦντας ἢ τοῦτο συγχωρήσαντας μηδὲν ἔτʼ ἔχειν εἰπεῖν ἕτερον αἴτιον τῆς διακρίσεως πλὴν τῆς ὁλκῆς. ἀλλʼ εἰ μὴ τῶν οὔρων ἡ φορὰ τῇ πρὸς τὸ κενούμενον ἀκολουθίᾳ γίγνεται, δῆλον, ὡς οὐδʼ ἡ τοῦ αἵματος οὐδʼ ἡ τῆς χολῆς ἢ εἴπερ ἐκείνων καὶ τούτου· πάντα γὰρ ὡσαύτως ἀναγκαῖον ἐπιτελεῖσθαι καὶ κατʼ αὐτὸν τὸν Ἐρασίστρατον. εἰρήσεται δʼ ἐπὶ πλέον ὑπὲρ αὐτῶν ἐν τῷ μετὰ ταῦτα γράμματι.