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 φυσικῶν δόξων. 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 decadence. In 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 βίοι 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.