"Also, that animals are born from one another by seeds, and that it is impossible for there to be any spontaneous production by the earth. And that seed is a drop from the brain which contains in itself a warm vapor; and that when this is applied to the womb it transmits virtue and moisture and blood from the brain, from which flesh and sinews and bones and hair and the whole body are produced. And from the vapor is produced the soul, and also sensation. And that the infant first becomes a solid body at the end of forty days; but, according to the principles of harmony, it is not perfect till seven, or perhaps nine, or at most ten months, and then it is brought forth. And that it contains in itself all the principles of life, which are all connected together, and by their union and combination form a harmonious whole, each of them developing itself at the appointed time. "The senses in general, and especially the sight, are a vapor of excessive warmth, and on this account a man is said to see through air and through water. For the hot principle is opposed by the cold one; since, if the vapor in the eyes were cold, it would have the same temperature as the air, and so would be dissipated. As it is, in some passages he calls the eyes the gates of the sun; and he speaks in a similar manner of hearing and of the other senses. "He also says that the soul of man is divided into three parts: into intuition and reason and mind, and that the first and last divisions are found also in other animals, but that the middle one, reason, is only found in man. And that the chief abode of the soul is in those parts of the body which are between the heart and the brain. And that that portion of it which is in the heart is the mind; but that deliberation and reason reside in the brain.