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. Democritus and Epicurus say, that the embryos in the womb receive their aliment by the mouth, for we perceive, as soon as ever the infant is born, it applies its mouth to the breast; in the wombs of women (our understanding concludes) there are little dugs, and the embryos have small mouths by which they receive their nutriment. The Stoics, that by the secundines and navel they partake of aliment, and therefore the midwife instantly after their birth binds the navel, and opens the infant’s mouth, that it may receive another sort of aliment. Alcmaeon, that they receive their nourishment from every part of the body; as a sponge sucks in water. CHAPTER XVII. WHAT PART OF THE BODY IS FIRST FORMED IN THE WOMB. The Stoics believe that the greater part is formed at the same time. Aristotle, as the keel of a ship is first made, so the first part that is formed is the loins. Alcmaeon, the head, for that is the commanding and the principal part of the body. The physicians, the heart, in which are the veins and arteries. Some think the great toe is first formed; others affirm the navel. CHAPTER XVIII. WHENCE IS IT THAT INFANTS BORN IN THE SEVENTH MONTH ARE BORN ALIVE.