143Ὅτι μὲν οὖν ἡ θρέψις ἀλλοιουμένου τε καὶ ὁμοιουμένου γίγνεται τοῦ τρέφοντος τῷ τρεφομένῳ καὶ ὡς ἐν ἑκάστῳ τῶν τοῦ ζῴου μορίων ἐστί τις δύναμις, ἣν ἀπὸ τῆς ἐνεργείας ἀλλοιωτικὴν μὲν κατὰ γένος, ὁμοιωτικὴν δὲ καὶ θρεπτικὴν κατ᾿ εἶδος ὀνομάζομεν, ἐν τῷ πρόσθεν δεδήλωται λόγῳ. τὴν δ᾿ εὐπορίαν τῆς ὕλης, ἣν τροφὴν ἑαυτῷ ποιεῖται τὸ τρεφόμενον, ἐξ ἑτέρας τινὸς ἔχειν ἐδείκνυτο δυνάμεως ἐπισπᾶσθαι πεφυκυίας τὸν οἰκεῖον χυμόν, εἶναι δ᾿ οἰκεῖον 144ἑκάστῳ τῶν μορίων χυμόν, ὃς ἂν ǁ ἐπιτήδειος εἰς τὴν ἐξομοίωσιν ᾖ, καὶ τὴν ἕλκουσαν αὐτὸν δύναμιν ἀπὸ τῆς ἐνεργείας ἑλκτικήν τέ τινα καὶ ἐπισπαστικὴν ὀνομάζεσθαι. δέδεικται δὲ καί, ὡς πρὸ μὲν τῆς ὁμοιώσεως ἡ πρόσφυσίς ἐστιν, ἐκείνης δ᾿ ἔμπροσθεν ἡ πρόσθεσις γίγνεται, τέλος, ὡς ἂν εἴποι τις, οὖσα τῆς κατὰ τὴν ἐπισπαστικὴν δύναμιν ἐνεργείας. αὐτὸ μὲν γὰρ τὸ παράγεσθαι τὴν τροφὴν ἐκ τῶν φλεβῶν εἰς ἕκαστον τῶν μορίων τῆς ἑλκτικῆς ἐνεργούσης γίγνεται δυνάμεως,
It has been made clear in the preceding discussion that nutrition occurs by an alteration or assimilation of that which nourishes to that which receives nourishment,1 and that there exists in every part of the animal a faculty which in view of its activity we call, in general terms, alterative, or, more specifically, assimilative and nutritive. It was also shown that a sufficient supply of the matter which the part being nourished makes into nutriment for itself is ensured by virtue of another faculty which naturally attracts its proper juice [humour] that that juice is proper to each part which is adapted for assimilation, and that the faculty which attracts the juice is called, by reason of its activity, attractive or epispastic.2 It has also been shown that assimilation is preceded by adhesion, and this, again, by presentation,3 the latter stage being, as one might say, the end or goal of the activity corresponding to the attractive faculty. For the actual bringing up of nutriment from the veins into each of the parts takes place through the activation of the attractive faculty,4 whilst to
- 1“Of food to feeder,” i.e. of the environment to the organism. cf. p. 39, chap. xi.
- 2“Drawing”; cf. p. 116, note 2.
- 3For these terms (prosthesis and prosphysis in Greek) cf. p. 39, notes 5 and 6.
- 4Lit. “through the energizing (or functioning) of the attractive faculty”; the faculty (δύναμις) in operation is an activity (ἐνέργεια). cf. p. 3, note 2.