Herophilus attributes a moving faculty to the nerves, arteries, and muscles, but believes that the lungs are affected only with a natural desire of enlarging and contracting themselves. Farther, there is the first operation of the lungs by attraction of the outward air, which is drawn in because of the abundance of the external air. Next to this, there is a second natural appetite of the lungs; the breast, pouring in upon itself the breath, and being filled, is no longer able to make an attraction, and throws the superfluity of it upon the lungs, whereby it is in turn sent forth by way of expiration; the parts of the body mutually concurring to this function by the alternate participation of fulness and emptiness. So that to lungs pertain four motions;—first, when the lungs receive the outward air; secondly, when the outward air thus entertained is transmitted to the breast; thirdly, when the lungs again receive that air which they imparted to the breast; fourthly, when this air then received from the breast is thrown outwards. Of these four motions two are dilatations, one when the lungs attract the external air, another when the breast dischargeth itself of it upon the lungs; two are contractions, one when the breast draws into itself the air, the second when it expels this which was insinuated into it. The breast admits only of two motions;—of dilatation, when it draws from the lungs the breath, and of contraction, when it returns what it did receive. CHAPTER XXIII. OF THE PASSIONS OF THE BODY, AND WHETHER THE SOUL HATH A SYMPATHETICAL CONDOLENCY WITH IT. The Stoics say that all the passions are seated in those parts of the body which are affected, the senses have their residence in the commanding part of the soul. Epicurus, that all the passions and all the senses are in those parts which are affected, but the commanding part is subject to no passion. Strato, that all the passions and senses of the soul are in the rational or commanding part of it, and are not fixed in those places which are affected; for in this part patience takes its residence, and this is apparent in terrible and dolorous things, as also in timorous and valiant persons. BOOK V. CHAPTER I. OF DIVINATION. Plato and the Stoics introduce divination as a divine enthusiasm, the soul itself being of a divine constitution, and this prophetic faculty being an inspiration, or an illapse of the divine knowledge into man; and so likewise they explain interpretation by dreams. And these same admit many divisions of the art of divination. Xenophanes and Epicurus utterly refuse any such art of foretelling future contingencies. Pythagoras rejects all manner of divination which is by sacrifices. Aristotle and Dicaearchus admit only these two kinds of it, a fury by a divine inspiration, and dreams; they deny the immortality of the soul, yet they affirm that the mind of man hath a participation of something that is divine. CHAPTER II. WHENCE DREAMS DO ARISE.