Note 130 — Chapter XXXVIII · TIMÆUS AND KRITIAS.
Reading edition
Galen, Hipp. et Plat. Dogm. viii. pp. 656-657, Kühn. ἐξ ὧν ἐπεραίνετο ἡ τῶν φλεβῶν ἀρχὴ τὸ ἧπαρ ὑπάρχειν· ᾧ πάλιν εἵπετο, καὶ τῆς κοινῆς πρὸς τὰ φυτὰ δυνάμεως ἀρχὴν εἶναι τοῦτο τὸ σπλάγχνον, ἥντινα δύναμιν ὁ Πλάτων ἐπιθυμητικὴν ὀνομάζει. Compare vi. 519-572, vii. 600-601.
The same triplicity of ἀρχαὶ in the organism had been recognised by Erasistratus, later than Aristotle, though long before Galen. Καὶ Ἐρασίστρατος δὲ ὡς ἀρχὰς καὶ στοιχεῖα ὅλου σώματος ὑποτιθέμενος τὴν τριπλοκίαν τῶν ἀγγείων, νεῦρα, καὶ φλέβας, καὶ ἀρτηρίας (Galen, T. iv. p. 375, ed. Basil). See Littré, Introduction aux Œuvres d’Hippocrate, T. i. p. 203.
Plato does not say, as Galen declares him to say, that the appetitive soul has its primary seat or ἀρχὴ in the liver. It has its seat between the diaphragm and the navel; the liver is placed in this region as an outlying fort, occupied by the rational soul, and used for the purpose of controuling the rebellious tendencies of the appetitive soul. Chrysippus (ap. Galen, Hipp. et Plat. Dogm. iii. p. 288, Kühn) stated Plato’s doctrine about the τριμερὴς ψυχὴ more simply and faithfully than Galen himself. Compare his words ib. viii. p. 651, vi. p. 519. Galen represents Plato as saying that nourishment is furnished by the stomach first to the liver, to be there made into blood and sent round the body through the veins (pp. 576-578). This is Galen’s own theory (De Usu Partium, iv. p. 268, Kühn), but it is not to be found in Plato. Whoever reads the Timæus, pp. 77-78, will see that Plato’s theory of the conversion of food into blood, and its transmission as blood through the veins, is altogether different. It is here that he propounds his singular hypothesis — the interior network of air and fire, and the oscillating ebb and flow of these intense agencies in the cavity of the abdomen. The liver has nothing to do with the process.
So again Galen (p. 573) puts upon the words of Plato about the heart — πηγὴν τοῦ περιφερομένου σφοδρῶς αἵματος — an interpretation conformable to the Galenian theory, but noway consistent with the statements of the Timæus itself. And he treats the comparison of the cranium and the rotations of the brain within, to the rotations of the spherical Kosmos — which comparison weighed greatly in Plato’s mind — as an illustrative simile without any philosophical value (Galen, H. et P. D. ii. 4, p. 230, Kühn; Plato, Tim. pp. 41 B, 90 A).