(18) ἐπὶ δὲ τῆς ἀλλοιώσεως ἔχει (19) τινὰ ἀπορίαν, μήποτε ἀναγκαῖον ᾖ τὸ ἀλλοιούμενον κατά τινα τῶν (20) λοιπῶν κινήσεων ἀλλοιοῦσθαι.
τοῦτο δὲ οὐκ ἀληθές ἐστιν·
σχεδὸν (21) γὰρ κατὰ πάντα τὰ πάθη ἢ τὰ πλεῖστα ἀλλοιοῦσθαι συμβέβη(22)κεν ἡμῖν οὐδεμιᾶς τῶν ἄλλων κινήσεων κοινωνοῦσιν·
οὔτε (23) γὰρ αὔξεσθαι ἀναγκαῖον τὸ κατὰ πάθος κινούμενον οὔτε (24) μειοῦσθαι, ὡσαύτως δὲ καὶ ἐπὶ τῶν ἄλλων,
ὥσθ’ ἑτέρα ἂν (25) εἴη παρὰ τὰς ἄλλας κινήσεις ἡ ἀλλοίωσις·
εἰ γὰρ ἦν ἡ (26) αὐτή, ἔδει τὸ ἀλλοιούμενον εὐθὺς καὶ αὔξεσθαι ἢ μειοῦσθαι (27) ἤ τινα τῶν ἄλλων ἀκολουθεῖν κινήσεων·
ἀλλ’ οὐκ ἀνάγκη.
(28) ὡσαύτως δὲ καὶ τὸ αὐξόμενον ἤ τινα ἄλλην κίνησιν κι(29)νούμενον ἀλλοιοῦσθαι·
(6) In commutatione uero est aliqua dubitatio, ne forte necesse sit quod (7) commutatur secundum aliquem reliquorum motuum commutari.
Hoc autem non (8) est uerum;
paene enim secundum omnes passiones uel multas commutari (9) nobis contingit nullo aliorum motuum communicante;
nam neque crescere (10) necesse est quod secundum passionem mouetur nec diminui, similiter (11) autem et in aliis:
quare diuersus erit motus ab aliis commutationibus
(12) (nam si idem esset, oporteret omne quod commutatur mox aut crescere (13) aut minui aut aliquem aliorum motuum consequi;
sed non est (14) necesse).
Similiter autem et quod crescit uel secundum quemlibet (15) alterum motum mutatur.
But in the case of alteration it may be argued that the process necessarily implies one or other of the other five sorts of motion.
This is not true,
for we may say that all affections, or nearly all, produce in us an alteration which is distinct from all other sorts of motion,
for that which is affected need not suffer either increase or diminution or any of the other sorts of motion.
Thus alteration is a distinct sort of motion;
for, if it were not, the thing altered would not only be altered, but would forthwith necessarily suffer increase or diminution or some one of the other sorts of motion in addition;
which as a matter of fact is not the case.
Similarly that which was undergoing the process of increase or was subject to some other sort of motion would, if alteration were not a distinct form of motion, necessarily be subject to alteration also.