Book 5
15
PLATO says, that the embryo is an animal; for, being contained in the mother’s womb, motion and aliment are imparted to it. The Stoics say that it is not an animal, but to be accounted part of the mother’s belly; like as we see the fruit of trees is esteemed part of the trees, until it be full ripe; then it falls and ceaseth to belong to the tree; and thus it is with the embryo. Empedocles, that the embryo is not an animal, yet whilst it remains in the belly it breathes. The first breath that it draws as an animal is when the infant is newly born; then the child having its moisture separated, the extraneous air making an entrance into the empty places, a respiration is caused in the infant by the empty vessels receiving of it. Diogenes, that infants are bred in the matrix inanimate, yet they have a natural heat; but presently, when the infant is cast into the open air, its heat draws air into the lungs, and so it becomes an animal. Herophilus acknowledgeth that infants have a natural, but not a respiratory motion, and that the nerves are the cause of that motion; that then they become animals, when being first born they suck in something of the air.
Chapter XVI. HOW EMBRYOS ARE NOURISHED, OR HOW THE INFANT IN THE BELLY RECEIVES ITS ALIMENT.
