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[165] 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,[166] 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.
[5] That is, “On the Natural Powers,” the powers of the Physis or Nature. By that Galen practically means what we would call the physiological or biological powers, the characteristic faculties of the living organism; his Physis is the subconscious vital principle of the animal or plant. Like Aristotle, however, he also ascribes quasi-vital properties to inanimate things, cf. Introduction, p. [xxvii].
[6] Ergon, here rendered an effect, is literally a work or deed; strictly speaking, it is something done, completed, as distinguished from energeia, which is the actual doing, the activity which produces this ergon, cf. p. [13], and Introduction, p. [xxx].
[7] Gk. psyche, Lat. anima.
[8] Gk. physis, Lat. natura.
[9] Motion (kinesis) is Aristotle’s general term for what we would rather call change. It includes various kinds of change, as well as movement proper, cf. Introduction, p. [xxix].
[10] “Conveyance,” “transport,” “transit”; purely mechanical or passive motion, as distinguished from alteration (qualitative change).
[11] “Waxing and waning,” the latter literally phthisis, a wasting or “decline;” cf. Scotch divining, Dutch verdwijnen.