PLATO, was instructed in grammar, music, and gymnastics by the most distinguished teachers of that time. ( Diog. Laert. iii. 4 ; comp. Hermann, Geschichte und System des Platonischen Systems^ p. 98, note 48, p. 99, note 49.) At an early age (e/c viov) he had become acquainted, through Cratylus, with the doctrines of Heracleitus (Arist. Metaph. i. 6 ; comp. Appuleius, de Doctr. Flat. p. 47. Elm.) ; through other instructors, or by means of writings, with the philosophical dogmas of the Eleatics and of Anaxagoras * (Diog. Laert. I. c. ; Vita Ation. ap. Tychsen, p, 13) ; and what is related in the Phaedo and Parmenides of the philosophical studies of the young Socrates, may in part be referable to Plato. In his 20th year he is said to have betaken himself to Socrates, and from that time onwards to have devoted himself to philosophy. (Diog. Laert. iii. 6 ; Suidas s. v. makes this into an intercourse of twenty years' duration with So- crates.) The intimacy of this relation is attested, better than by hearsay accounts and insufficient testimonies (Diog. Laert. iii. 5 ; Paus. i. 30. § 3, &c. ; Xen. Metn. iii. 6. § 1), by the enthusiastic love with which Plato not only exhibits Socrates as he lived and died — in the Banquet and the Phaedo, — but also glorifies him by making him the leader of the investigations in the greater part of his dialogues ; not as though he had thought himself secure of the assent of Socrates to all the conclusions and developments which he had him- self drawn from the few though pregnant principles of his teacher, but in order to express his con- viction that he had organically developed the re- sults involved in the Socratic doctrine. It is therefore probable enough that, as Plutarch relates {Afarius, 46 ; comp. Lactant. Div. hist. iii. 19. § 17), at the close of his life he praised that dis- pensation which had made him a contemporary of Socrates. After the death of the latter he betook himself, with others of the Socratics, as Hermo- dorus had related, in order to avoid threatened persecutions (Diog. Laert. ii. 106, iii. 6), to Eu- cleides at Megara, who of all his contemporaries had the nearest mental affinity with him. That Plato during his residence in Megara composed several of his dialogues, especially those of a dia- lectical character, is probable enough, though there is no direct evidence on the subject (Ast, vom Leben und den Scriften des Plato, p. 51 ; Van Heusde, Init. Plat. doct. i. p. 72 ; Hermann, ibid. pp. 46, 490). The communication of the Socratic conversation recorded in the Theaetetus is referred to Eucleides, and the controversial examination, contained in the Sophistes (p. 246) and apparently directed against Eucleides and his school, of the tenets of the friends of certain incorporeal forms (ideas) cognisable by the intellect, testifies esteem for him. Friendship for the mathematician Theo- doras (though this indeed does not manifest itself in the way in which the latter is introduced in the Theaetetus) is said to have led Plato next to Cyrene (Diog. Laert. iii. 6 ; Appul. /. c). Through his eagerness for knowledge he is said to have been induced to visit Egypt, Sicily, and the Greek cities in Lower Italy (Cic. de Rep. i. 10, de Fin.
- Hermogenes is mentioned as the Eleatic
teacher of Plato, probably through a misunder- standing of the mention of him in the Cratylus, pp. 384, 394 ; in the anonymous writer, Herroippus is named with hardly better reason. PLATO. 393 V. 29 ; Val. Max. viii. 7. § 3 ; Vita Anon. I. c). Others, in inverted order, make him travel first to Sicily and then to Egypt (Quintil. i. 12. § 15; Diog. Laert. iii. 6), or from Sicily to Cyrene and Egypt, and then again to Sicily (Appuleius, /. c. p. 47 ; comp. Clinton, F. H. vol. ii. p. 366). As his companion we find mentioned Eudoxus (Strab. xvii. 29, in opposition to Diog. Laert. viii. 87), or Simmias (Plut. de Daem.Socr. 7), or even Euri- pides, who died 01. 93. 2 (Diog. Laert. iii. 6). More distant journeys of Plato into the interior of Asia, to the Hebrews, Babylonians, and Assy- rians, to the Magi and Persians, are mentioned only by writers on whom no reliance can be placed (Clem. Alex. adv. Gent. p. 46 ; Vita Anon. p. 14 ; comp. Diog. Laert. iii. 7 ; Lactant. Instit. iv. 2 ; comp. Cic. l^usc. Disp. iv. 19). Even the fruits of his better authenticated journeys cannot be traced in the works of Plato with any definiteness. He may have enlarged his mathematical and astrono- mical knowledge, have received some impulses and incitements through personal intercourse with Archytas and other celebrated Pythagoreans of his age (Clem. Alex. Cic. Val. Max. &c. II. cc), have made himself acquainted with Egyptian modes of life and Egyptian wisdom (Plat. deLeg. ii. p. QoQ, vii. pp.799, 819, Phaedo, p. 274, Phileb. p. 18, Tim. 21 ; comp. Epinom. p. 986) ; but on the fundamental assumptions of his system, and its development and exposition, these journeys can hardly have exercised any important influence ; of any eflFect produced upon it by the pretended Egyptian wisdom, as is assumed by Plessing (Memnoniiim, ii. p. 288, &c., 504, &c. ; Versuch zur Aufkl'drung der Philosophie des altesten Alter- thums, ii. 2, p. 879, &c.) and others, no traces are to be found (comp. Hermann, /. c. i. 55, &c.). That Plato during his residence in Sicily, through the intervention of Dion, became acquainted with the elder Dionysius, but very soon fell out with the tyrant, is asserted by credible witnesses (espe- cially by Hegesander ap. Athen. xi. 116, p. 507, b ; Died, xv, 7 ; Plut. Dion, 4, 5 ; Diog. Laert. iii. 18, 19. The Platonic epistle vii. pp. 324, 326, 327, mentions only the acquaintance with Dion, not that with the elder Dionysius). More doubt attaches to the story, according to which he was given up by the tyrant to the Spartan ambassador Pollis, by him sold into Aegina, and set at liberty by the Cyrenian Anniceris. This story is told in very different forms. On the other hand, we find the statement that Plato came to Sicily when about forty years old, so that he would have returned to Athens at the close of the 97th Olympiad (B.a 389 or 388), about twelve years after the death of Socrates ; and perhaps for that reason 01. 97. 4, was set down by the chronologers whom Eusebius follows as the period when he flourished. After his return he began to teach, partly in the gymna- sium of the Academy and its shady avenues, near the city, between the exterior Cerameicus and the hill Colonus Hippius, partly in his garden, which was situated at Colonus (Timon ap. Diog. Laert. iii. 7, comp. 5 ; Plut. de Exilio,c. 10, &c.). Respecting the acquisition of this garden again, and the circumstances of Plato as regards property generjdly, we have conflicting accounts (Plut. Diog. Laert. Appul. //. cc. ; A. Gell. A^. A. iii. 17, comp. Hermann, /. c. p. 77, &c.). Plato taught gratuitously (Diog. Laert. iv. 2 ; Olympiod. et Anon.), and agreeably to his maxims {Phacd. p.
