sthenes calls him a pupil of Anaximenes ; but he lived in Anaxagoras's time. This man, a so great was his unpopularity at Athens, almost lost his life, as Demetrius of Phalerum states in his Defence of Socrates. The doctrines of Diogenes were as folio ws. b Air is the universal element. There are worlds unlimited in number, and unlimited empty space. Air by condensation and rarefaction generates the worlds. Nothing comes into being from what is not or passes away into what is not. The earth is spherical, firmly supported in the centre, having its construction determined by the revolution which comes from heat and by the congealment caused by cold. The words with which his treatise begins are these : At the beginning of every discourse I consider that one ought to make the starting-point unmistakably clear and the exposition simple and dignified." Chapter 10. ANAXARCHUS Anaxarchus, a native of Abdera, studied under Diogenes of Smyrna, and the latter under Metrodorus of Chios, who used to declare that he knew nothing, not even the fact that he knew nothing while Metrodorus Mas a pupil of Nessas of Chios, though some say that he was taught by Democritus. Now Anaxarchus accompanied Alexander and flourished in the 110th Olympiad/* He made an enemy of Nicocreon, tyrant of Cyprus. Once at a