BOOK VI. ANTISTHENES 217 DIOGENES 224 MONIMUS 248 ONESICRITUS 249 CRATES 249 METROCLES 253 HIPPARCHIA 254 MENIPPUS 256 MENEDEMUS 257 BOOK VII. ZENO 259 ARISTON 318 HERILLUS 320 DIONYSIUS 321 CLEANTHES 322 SPHÆRUS 326 CHRYSIPPUS 327 BOOK VIII. PYTHAGORAS 338 EMPEDOCLES 359 EPICHARMUS 368 ARCHYTAS 369 ALCMÆON 371 HIPPASUS 371 PHILOLAUS 372 EUDOXUS 372 BOOK IX. HERACLITUS 376 XENOPHANES 382 PARMENIDES 384 MELISSUS 386 ZENO, THE ELEATIC 386 LEUCIPPUS 388 DEMOCRITUS 390 PROTAGORAS 397 DIOGENES, OF APOLLONIA 400 ANAXARCHUS 400 PYRRHO 402 TIMON 420 BOOK X. EPICURUS 424 PREFACE. Diogenes, the author of the following work, was a native (as is generally believed) of Laërte, in Cilicia, from which circumstance he derived the cognomen of Laërtius. Little is known of him personally, nor is even the age in which he lived very clearly ascertained. But as Plutarch, Sextus Empiricus, and Saturninus are among the writers whom he quotes, he is generally believed to have lived near the end of the second century of our era: although some place him in the time of Alexander Severus, and others as late as Constantine. His work consists of ten books, variously called: The Lives of Philosophers, A History of Philosophy, and The Lives of Sophists. From internal evidence (iii. 47, 29), we learn that he wrote it for a noble lady (according to some, Arria; according to others, Julia, the Empress of Severus), who occupied herself with the study of philosophy, and especially of Plato.