§6Κάλλιον δ’ εἶναί μοι δοκοῦσι ποιεῖν οἱ ζητοῦντες, ἆρά γε τὴν διαστολὴν, ἢ τὴν συστολὴν, ἢ ἀμφοτέρας ἐνεργείας χρὴ νομίζειν τῶν ἀρτηριῶν, ὥσπερ, οἶμαι, καὶ περὶ τῶν τῆς ἀναπνοῆς μερῶν εὐλόγως ἐζητήθη, πότερον τὴν ἐκπνοὴν, ἢ τὴν εἰσπνοὴν, ἢ ἀμφοτέρας ἐνεργείας ὑποληπτέον ὑπάρχειν.
Those who inquire whether one should consider the dilation, or the contraction, or both to be activities of the arteries, seem to me to act better, just as, I think, it was also reasonably inquired concerning the parts of respiration, whether one should suppose the exhalation, or the inhalation, or both to be activities.
ἀλλὰ περὶ μὲν ἐκείνων ἐν ἑτέροις εἴρηται τὰ εἰκότα, περὶ δὲ τῆς τῶν σφυγμῶν κινήσεως νῦν ζητητέον.
But concerning those matters, what is plausible has been said in other places, and now we must inquire about the movement of the pulses.
εἰ μὲν οὖν, ὥσπερ εἴρηται, τῆς αὐτῆς ἐνεργείας ἕνεκα γεγόνασιν ἀναπνοή τε καὶ σφυγμὸς καὶ πρὸς τῶν αὐτῶν δημιουργουσῶν δυνάμεων, ῥᾴδιον ἂν εἴη τῇ πρὸς ἐκείνην ὁμοιότητι καὶ περὶ τῶν σφυγμῶν τι τεκμήρασθαι.
If, therefore, as has been said, both respiration and pulse have come to be for the sake of the same activity and by the same demiurgic powers, it would be easy to infer something about the pulses also by similarity to that.
ἐπεὶ δὲ τῶν μὲν σφυγμῶν ἡ ζωτικὴ δύναμις ἡ ἀπὸ τῆς καρδίας ὁρμωμένη δημιουργὸς, τῆς δ’ ἀναπνοῆς, ὡς ἐδείξαμεν, ἡ ἀπ’ ἐγκεφάλου ψυχικὴ, οὐδὲν ἂν ἡμῖν ἐκ τῶν ὑπὲρ ἐκείνης εὑρημένων εὐποροῖ τῆς πρὸς τὰ παρόντα χαλεπωτέρας δήπου τῆς εὑρέσεως, καὶ διότι μετὰ τὸν θάνατον οὐχ ὥσπερ τὰς φλέβας ἔστιν ἰδεῖν εἰς ἑαυτὰς συμπιπτούσας, οὕτω καὶ τὰς ἀρτηρίας.
But since the demiurge of the pulses is the vital power starting from the heart, while that of respiration, as we showed, is the psychic power from the brain, nothing of what has been discovered concerning the latter would facilitate for us the discovery for the present matters, which is indeed more difficult, also because after death it is not possible to see the arteries collapsing into themselves in the way that one can see the veins doing so.
αἱ μὲν γὰρ, ὅταν κενωθῶσι τοῦ αἵματος, εἰς ἑαυτὰς συνιζάνουσι τελέως, ὥστε τοὺς ἄνωθεν αὐτῶν χιτῶνας ἐπιπίπτειν τοῖς κάτωθεν, αἱ δ’ ἀρτηρίαι μέχρι παντὸς διεστηκυῖαι φαίνονται, διὰ τὸν ἕτερον δηλονότι τῶν ἐν αὐταῖς χιτώνων τὸν σκληρόν.
For the veins, when they are emptied of blood, collapse completely into themselves, so that their upper tunics fall upon the lower ones, but the arteries appear dilated to the end, obviously because of the other of the tunics in them, namely the hard one.
καίτοι τινὲς καὶ αὐτὸ τοῦτο μετὰ τὸν θάνατον γίνεσθαί φασι, πηγνυμένων ὑπὸ τῆς ψύξεως αὐτῶν καὶ οὐ φύσει τοιούτων οὐσῶν.
And yet some say that this very thing happens after death, since they are congealed by the cold and are not of such a nature naturally.
ἕτεροι δὲ εἰς θερμὸν ὕδωρ ἐμβαλόντες, εἶτ’ ἔτι διεστώσας ὁρῶντες, οὕτω πείθονται διακεῖσθαι καὶ πρὸ τοῦ θανάτου· ἐπανελθεῖν γὰρ ἂν εἰς τὴν ἀρχαίαν φύσιν, ἀπελθούσης τῆς ψύξεως, εἰ δὴ ταύτῃ τι ἐνενεωτέριστο.
But others, having cast them into warm water and then seeing them still dilated, are persuaded that they are in this state also before death; for they would have returned to their ancient nature, the cold having departed, if indeed any innovation had been made by this.
παντοίως οὖν ἀπόρου τοῦ ζητουμένου ὄντος, οἷς τεκμαιρόμενος ἀμφοτέρας τὰς κινήσεις τῶν ἀρτηριῶν ἐνεργείας εἶναι νομίζω, καὶ δὴ φράσω.
Therefore, since the question is in every way difficult, I will indeed state the signs from which I infer that both movements of the arteries are activities.
τὴν μὲν διαστολὴν, ἔτι τῆς δυνάμεως ἐῤῥωμένης, μεγάλην γίνεσθαι, ὥσπερ τοὐναντίον, αὐτῆς ἀσθενούσης, μικρὰν εἶναι, πᾶσι πρόδηλον.
That the dilation becomes large while the power is still strong, just as conversely it is small when the power is weak, is clear to everyone.
ἐχρῆν δὲ, εἴπερ, ὥς τινες οἴονται, τὸ μὲν συστέλλεσθαι τῶν ἀρτηριῶν ἐνέργεια, τὸ δὲ διαστέλλεσθαι εἰς τὴν κατὰ φύσιν τῶν χιτώνων διάστασιν ἐπάνοδος αὐτόματος, πρῶτον μὲν ἴσον ἀεὶ τὸν ὄγκον ὑπάρχειν τῶν διαστολῶν, ἔπειτα μηδὲν μᾶλλον ἐῤῥωμένης ἢ ἀῤῥώστου δυνάμεως εἶναι ἔργον τὸ μέγεθος· οὐδέτερον δ’ οὕτως ἔχει.
But if, as some think, the contraction of the arteries is an activity, while the dilation is an automatic return to the natural state of expansion of the tunics, it would be necessary, first, that the volume of the dilations be always equal, and second, that the size be in no way the effect of a strong rather than a weak power; but neither is the case.
καὶ πρόσεστιν ἕτερον τεκμήριον οὐ μικρὸν εἰς ταὐτὸν συντελοῦν.
And there is another not small evidence contributing to the same conclusion.
μέγιστοι καὶ ὑψηλότατοι σφυγμοὶ τοῖς κάλλιστα κριθησομένοις γίνονται.
The greatest and highest pulses occur in those who are about to have the best crisis.
καίτοι τότ’ οὐκ ἄν τις οὐδὲ μαινόμενος εἴποι τὴν δύναμιν ἀῤῥωστεῖν.
And yet, no one, not even a madman, would say then that the power is weak.
εἰ γὰρ τὸ καλῶς κριθῆναι γίνεται ἐνδείᾳ δυνάμεως, τὸ κακῶς δι’ εὐρωστίαν δηλονότι γενήσεται· εἰ δὲ τοῦτο, καὶ τὸ ἀποθανεῖν αὐτὸ ῥώμης ἔργον εἶναι φήσομεν.
For if the favorable crisis occurs through a deficiency of power, the unfavorable one will obviously occur through strength; and if so, we shall say that dying itself is an effect of strength.
τί οὖν ἂν εἴη γελοιότερον;
What, then, could be more ridiculous?
ἀλλὰ καὶ τὸ τὸ σφοδρὸν τῆς πληγῆς ἐν τῷ διαστέλλεσθαι τοῖς μὲν μᾶλλον, τοῖς δὲ ἧττον ὑπάρχειν τῶν σφυγμῶν ἐπίτασιν καὶ ἄνεσιν ἐνεργείας ἐνδείκνυται.
Moreover, the fact that the vehemence of the stroke during dilation is present more in some pulses and less in others indicates the intensification and relaxation of an activity.
εἰ δὲ τὸ φαῦλον τῆς ἐνεργείας ἦν ἡ διαστολὴ, καθάπερ ἡ ἐκπνοὴ, οὔτ’ ἂν τὸ μᾶλλόν τε καὶ ἧττον ἦν ἐν αὐτῇ, καθὰ ἐν ταῖς ἐκπνοαῖς, οὔθ’ ὅλος ὁ τόνος τε καὶ ἡ σφοδρότης τῆς προσβολῆς.
But if the dilation were the absence of activity, just as exhalation is, there would neither be the more and the less in it, as there is in exhalations, nor indeed would there be tension and vehemence of impact at all.
ἡ μὲν οὖν διαστολὴ διὰ ταῦτά τε καὶ ἄλλα παραπλήσια τούτοις ἐκ τοῦ τῶν ἐνεργειῶν εἶναί μοι φαίνεται γένους, καὶ σώζοιτ’ ἂν ἔτι καὶ κατὰ τοῦτο ἡ πρὸς τὴν ἀναπνοὴν τῶν σφυγμῶν ὁμοιότης.
Dilation, therefore, because of these and other similar things, seems to me to belong to the class of activities, and in this way also the similarity of the pulses to respiration would still be preserved.