examined the more important sources of fragments, in order that the student may be able to estimate the relative value of the sources, both as to text and as to directness of transmission, in his own study of them.

II.

§ 15.(Turning now to the doxographic tradition, we may state the problem as follows: In the Placita philosophorum attributed to Plutarch, in the Eclogae physicae of Stobaeos, in fragments from Arius Didymos, in Hippolytos, and in other writers, we find copious statements as to the opinions of the early philosophers. These opinions shed light on many points not mentioned in the fragments of their writings now remaining, and so they have great importance for the student of their systems. At the same time they are often confused and unreliable. The problem is to determine the relation of these writers to each other, as well as to the source of the whole series, in order that we may estimate their relative value. This work has been most successfully accomplished in the Prolegomena to Diels' Doxographi Graeci, a work that is absolutely indispensable to the student of this subject. There is no occasion to reopen here a question that Diels has so successfully solved, but I propose to state briefly a few of the conclusions which the reader will find substantiated in the work of Diels.

The most obvious fact to one who takes up the study of the doxographic writers is that the Placita attributed to Plutarch, and the Eclogae physicae, which was originally a part of the Florilegium of Stobaeos, are intimately related; and when the two are printed side by side, as the reader finds them in the text of Diels, the likeness of the two is most striking. At the same time the two books are not identical, and each gives much material that the other omits. Stobaeos cannot have copied from the work attributed to Plutarch, for even in passages that occur in the Placita Stobaeos not infrequently gives the fuller form; nor can the writer of the Placita have copied from Stobaeos, for his work can be traced back nearly three centuries before the time of Stobaeos. It was used by

Athenagoras in his defence of the Christians 177 A.D. (Dox. p. 4); it was mentioned by Theodoret (Dox. p. 47); and important corrections of the text are made by Diels on the authority of Eusebios, Cyril, and the pseudo-Galen, all of whom had used it. Theodoret (Therap. IV. 31, Dox. 47) mentions the epitome by Plutarch, but only after he has mentioned the Placita of Aetios, Αετίου τὴν περὶ ἀρεσκόντων συναγωγήν, and it is this work of Aetios which Diels vindicates as the source both of Plutarch and of Stobaeos, while Theodoret also quotes from it occasionally. A careful study of these three writers and their methods enables Diels to reconstruct a large part of the work of Aetios; and it is the sections of this work bearing on the earlier philosophers which I have translated (see III. English Index under 'Aetios '). Of Aetios himself almost nothing is known; the work assigned to him must have been written between the age of Augustus and the age of the Antonines (Dox. 100). It was in four books, divided into chapters by topics, and in each chapter the opinions of the philosophers were given not by schools but by affinity of their opinions.

§ 16. Fortunately we are in a position to say what was the beginning of that style of composition of which the work of Aetios is an example. Aristotle, as we have seen, paid considerable attention to the earlier thinkers and often stated their opinions as the introduction to his own position. A list of the works of his pupil and successor Theophrastos is given by Diogenes Laertios (v. 46, 48), and in the list there is mentioned a book in eighteen chapters περὶ τῶν φυσικῶν, and a little later another book in sixteen chapters of pvoIK@V Sógov. We have a long fragment de sensibus which Diels has edited in connection with the later doxographists (Dox. pp. 499 f.), and from this we can learn something of his method. In this fragment he discusses the opinions of his predecessors as to sense-perception, grouping them by affinity, and not chronologically or by schools. The work is done conscientiously, and is based on a study of the original writings of the thinkers he treats (v. supra, pp. 230 f.). Other fragments from the first book have been pointed out by Brandis and Usener (Analecta Theophrastea) in Simplicius' Commentary on

Aristotle's Physics; while we have also several pages preserved in Philo de incorrupt. mundi. In the first book, to judge from the fragments in Simplicius, Theophrastos arranged the earlier thinkers by schools and accompanied his statements with brief biographical notices (e.g. pp. 11, 257 supra). Such a work was of the greatest convenience to later writers, and especially to the compilers who were so numerous in the age of the decadenceIn fact the whole doxographic tradition may be traced back to this work of Theophrastos.

In the last centuries of the pre-Christian era there was an unusual interest in the biographies of famous men. Apocryphal anecdotes were gathered from popular gossip, deduced from the works of these writers, or made up with no foundation at all. In the second century several writers of the peripatetic school wrote the lives of the philosophers after this fashion. We hear of ẞío by Hermippos and by Satyros, and of the διαδοχαὶ τῶν φιλοσόφων of Satyros; and we are told that Herakleides of Lembos worked over what his immediate predecessors had collected. Phanias of Eresos is one of the ' authorities' of this school. Much of this material has come down to us in the work of Diogenes Laertios.

On the book of Theophrastos, and on the 'Lives' or the 'Successions of the philosophers,' as they were often called, the later doxographic writers based their work. Even in Diogenes Laertios there is material from both sources, and we can define some fragments almost in Theophrastos' own words.) In the Philosophumena of Hippolytos the two sources are pretty clearly distinguished: chapters 1-4 and 10 (on Thales, Pythagoras, Empedokles, Herakleitos and Parmenides, see III. English Index under Hippolytos') are made up of personal anecdotes such as writers of the lives were eager to collect and to repeat; chapters 6-8 and 11 (on Anaximandros, Anaximenes, Anaxagoras, and Xenophanes) come indirectly from the work of Theophrastos. The Stromateis attributed by Eusebios to Plutarch (see III. English Index under ' Plutarch,' and Dox. pp. 579 f.) are like the last-mentioned chapters of Hippolytos, though the language is often more careless.

A comparison of Aetios with Hippolytos, the Stromateis, and the doxographic material in Cicero and Censorinus (from

Varro) makes it clear that the Placita of Aetios are not based directly on the work of Theophrastos. Indeed (Dox. p. 100, and pp. 178 f.) it is evident from an examination of the work of Aetios by itself that much of his material is drawn from Stoic and Epicurean sources. As the main source for what remains after Stoic and Epicurean passages have been cut out, Diels postulates an earlier Placita (Vetusta placita, pp. 215 f.). He finds traces of this in the work of Varro as used by Censorinus, in Cicero's Tusculan Disputations, and in some later writers.

$ 17. Résumé. (The doxographic tradition starts with

the work of Theophrastos on the opinions of his predecessors. On this work is based immediately the Vetusta placita; on the Vetusta placita is based the Placita of Aetios, and there are traces of its use by later writers; the Placita of Aetios may be partially reconstructed from Plutarch's Placita and Stobaeos' Eclogae. Again, using Theophrastos and gathering anecdotes from every side, writers of the second century B.C. wrote the lives of the philosophers.) A line of tradition probably independent of the Placita just considered appears in the work of Hippolytos, who used now the work of Theophrastos, now the lives; in Diogenes Laertios, where material from most various sources is indiscriminately mixed; and in the Stromateis attributed to Plutarch by Eusebios, which are related to the better material of Hippolytos. Simplicius used Theophrastos directly. Finally in the fragments of Philodemos and the related material in Cicero's Lucullus and De natura deorum we find traces of a use of Theophrastos either by Philodemos himself, or in a common source of both Cicero and Philodemos-probably a Stoic epitome of Theophrastos made by the Phaedros whom Cicero mentions.

INDEXES

I. INDEX OF SOURCES

The references are to the critical notes.
Zeno (Z.), Melissos (M.), and Anaxagoras
menides (P.) and Empedokles (E.) by lines.