Book 2
3
Now, it is not for the wax to discover for itself how much of it is required; that is the business of Phidias. Accordingly the artificer will draw to itself as much blood as it needs. Here, however, we must pay attention and take care not unwittingly to credit the semen with reason and intelligence; if we were to do this, we would be making neither semen nor a nature, but an actual living animal.i.e.. we should be talking psychology, not biology; cf. stomach, p. 307, note 3. And if we retain these two principles — that of proportionate attraction,Attraction now described not merely as qualitative but also as quantitative. cf. p. 85, note 3. and that of the non-participation of intelligence — we shall ascribe to the semen a faculty for attracting blood similar to that possessed by the lodestone for iron.He still tends either to biologize physics, or to physicize biology — whichever way we prefer to look at it. cf. Book I., chap. xiv. Here, then, again, in the case of the semen, as in so many previous instances, we have been compelled to acknowledge some kind of attractive faculty. And what is the semen? Clearly the active principle of the animal, the material principle being the menstrual blood.Aristotelian and Stoic duality of an active and a passive principle. Next, seeing that the active principle employs this faculty primarily, therefore, in order that any one of the things fashioned by it may come into existence, it [the principle] must necessarily be possessed of its own faculty. How, then, was Erasistratus unaware of it, if the primary function of the semen be to draw to itself a due proportion of blood? Now, this fluid would be in due proportion if it were so thin and vaporous, that, as soon as it was drawn like dew into every part of the semen, it would everywhere cease to display its own particular character; for so the semen will easily dominate and quickly assimilate it — in fact, will use it as food. It will then, I imagine, draw to itself a second and a third quantum, and thus by feeding it acquires for itself considerable bulk and quantity.Note that early embryonic development is described as a process of nutrition. cf. p. 130, note 2. In fact, the alterative faculty has now been discovered as well, although about this also has not written a word. And, thirdly the shaping On the alterative and shaping of faculties cf. p. 18, note 1.faculty will become evident, by virtue of which the semen firstly surrounds itself with a thin membrane like a kind of superficial condensation; this is what was described by Hippocrates in the sixth-day birth, which, according to his statement, fell from the singing-girl and resembled the pellicle of an egg. And following this all the other stages will occur, such as are described by him in his work On the Child's Nature.
