remedies now used, which was neither necessary in ancient times, nor is yet in other nations, scarcely protracts the lives of a few of us to the verge of old age. For the same reason, after those, whom I have mentioned, no men of eminence practised medicine, till learning began to be pursued with greater application; which, as it is of all things most necessary to the mind, so it is no less hurtful to the body. And at first the science of healing was accounted a branch of philosophy; so that the cure of diseases, and the study of nature, owed their rise to the same persons: and for this very good reason, because they, who had impaired their bodies by anxious thought, and nightly watchings, stood most in need of its assistance. And thus we find, that many amongst the philosophers were skilled in this science; of whom the most celebrated were Pythagoras, Empedocles, and Democritus. Hippocrates of Cos, who, according to some authors, was the disciple of the last mentioned of these, and is so justly admired both for his knowledge in this profession, and for his eloquence, was the first worthy of notice, who separated medicine from the study of philosophy. After him, Diocles the Carystian, then Praxagoras and Chrysippus; after these, Herophilus and Erasistratus applied themselves to this art, and differed widely from each other in their methods of cure. (1) For references 1, 2, 3, &c. see Notes at the end. During this period, physick was divided into three parts: the first cured by diet, the second by medicines, the third by manual operations: the first they termed, in Greek, Diætetice,[X] the second Pharmaceutice,[Y] and the third Chirurgice.[Z] The most illustrious professors of that branch, which treats diseases by diet, endeavoured to extend their views farther, and took in the assistance of natural philosophy; being persuaded that, without it, medicine would be a weak and imperfect science. After these came Serapion, who first of all maintained, that the rational method of study was foreign to the art of medicine, and confined it to practice and experience. In his steps followed Appollonius and Glaucias, and some time after Heraclides of Tarentum, and others of no small note; who, from the doctrine they asserted, stiled themselves Empiricks[AA]. And thus the Dietetick branch was also divided into two parts, one set of physicians pursuing theory, the other following experience alone. However, after these we have enumerated above, no one attempted any thing new, till Asclepiades, who greatly changed the art of medicine. And Themison, one of his successors, has also lately, in his old age, departed from him in some things. And these are the men, to whom we are chiefly indebted for the improvements made in this salutary profession. [X] Διαιτητικὴ. [Y] Φαρμακευτικὴ. [Z] Χειρουργικὴ. [AA] Εμπειρικοὶ.