XII. Again, of philosophers some derived a surname from cities, as, the Elians, and Megaric sect, the Eretrians, and the Cyrenaics. Some from the places which they frequented, as the Academics and Stoics. Some from accidental circumstances, as the Peripatetics; or, from jests, as the Cynics. Some again from their dispositions, as the Eudæmonics; some from an opinion, as the Elenctic, and Analogical schools. Some from their masters, as the Socratic and Epicurean philosophers; and so on. The Natural Philosophers were so called from their study of nature; the Ethical philosophers from their investigation of questions of morals (περὶ τὰ ἔθη). The Dialecticians are they who devote themselves to quibbling on words. XIII. Now there are three divisions of philosophy. Natural, Ethical, and Dialectic. Natural philosophy occupies itself about the world and the things in it; Ethical philosophy about life, and the things which concern us; Dialectics are conversant with the arguments by which both the others are supported. Natural philosophy prevailed till the time of Archelaus; but after the time of Socrates, Ethical philosophy was predominant; and after the time of Zeno the Eleatic, Dialectic philosophy got the upper hand. Ethical philosophy was subdivided into ten sects; the Academic, the Cyrenaic, the Elian, the Megaric, the Cynic, the Eretrian, the Dialectic, the Peripatetic, the Stoic, and the Epicurean. Of the old Academic school Plato was the president; of the middle, Arcesilaus; and of the New, Lacydes:—the Cyrenaic school was founded by Aristippus the Cyrenian; the Elian, by Phædo, of Elis; the Megaric, by Euclid, of Megara; the Cynic, by Antisthenes, the Athenian; the Eretrian, by Menedemus, of Eretria; the Dialectic by Clitomachus, the Carthaginian; the Peripatetic, by Aristotle, the Stagirite; the Stoic, by Zeno, the Cittiæan; the Epicurean school derives its name from Epicurus, its founder. But Hippobotus, in his Treatise on Sects, says that there are nine sects and schools: first, the Megaric; secondly, the Eretrian; thirdly, the Cyrenaic; fourthly, the Epicurean; fifthly, the Annicerean; sixthly, the Theodorean; seventhly, the sect of Zeno and the Stoics; eighthly, that of the Old Academy; and ninthly, the Peripatetic;—not counting either the Cynic, or the Eliac, or the Dialectic school. That also which is called the Pyrrhonean is repudiated by many writers, on account of the obscurity of its principles. But others consider that in some particulars it is a distinct sect, and in others not. For it does appear to be a sect—for what we call a sect, say they, is one which follows, or appears to follow, a principle which appears to it to be the true one; on which principle we correctly call the Sceptics a sect. But if by the name sect we understand those who incline to rules which are consistent with the principles which they profess, then the Pyrrhonean cannot be called a sect, for they have no rules or principles.