From, A History of Greek Philosophy, vol. IV, Plato: the man and his dialogues, earlier period,
Cambridge University Press, 19896, pp. 8-38.
 Cic. Rep. 1.10.16, Fin. 5.29.87. For a full discussion of the evidence see Kerschensteiner, Ρ. u. d. 0rient 46 ff.; more briefly Leisegang in RE, 2350. The evidence οf the Herculanean Index Acad. (ed. Merkel, p. 6 col. 10) is of no value, since it contradicts the 7th Letter by putting Plato’s first voyage to Italy and Sicily immediately after Socrates’s death, when he was 27. In any case, no one who has looked at the mutilated text in Merkel, as distinct from the reconstruction, will be likely to put much faith in it. Cyrene is mentioned only by Apuleius, D.L. and Olympiodorus. (Kerschensteiner 47f.)
 ‘In any event, if Plato did not write them [sc. Εpp. 7 and 8] himself, they were written not long after his death by one of his disciples, possibly by Speusippus.’ (Μ. Ι. Finley, Aspects of Antiquity 80.) Νο sceptic, Ι believe, would go further than this today, and history will not suffer if in the text Ι occasionally refer to ‘Plato’ as saying this or that.
 Cornford, ‘Plato’s Commonwealth’, in Unwritten Ρhil. 52.
 See especially νon Fritz, Ρ. in Sizilien und das Problem der Philosophenherrschaft (1968).
 For Archytas see νοl. I, 333-6; for Plato’s motive in going to Ιtaly, Cic. Fin. 5.29.87, Rep. 1.10.16, Tusc. 1.17.39.
 Βίος εὐδαίμων 326b. The apt translation is von Fritz’s.
 Ε.g. D.L. 3.18 and Ath. 11.507b. Ι do nοt mean to imply that Plato could not have been interested in such natural phenomena (Phaedo 111e and 113b suggest that he was), but only that if there had been any excuse to assign political motives these writers would surely have done so. Diod. (15.7), whose whole remark about Plato is an aside, does say that he was invited by Dionysius. Τσ secure an invitation (perhaps through Archytas) would have been advisable anyway.
 Looked at in the setting οf its times, Ι do not know why the last line of the epigram on Dion ascribed to Plato (ὦ ἐμὸν ἐκμήνας θυμὸν ἔρωτι Δίων) should have ‘made critics doubtful οf its authorship’ (Harward, Εpp. 17 n.). It is quite appropriate to the author οf the Symposium and Phaedrus.
 The passage 327b-d would itself be evidence that the letter was written for readers contemporary and familiar with the events alluded to, who could fill in the gaps for themselves.
 The Index Acad. (p. 16 n. 1) is usually cited as the earliest source for the story, but its fragmentary text is quite unreliable. Diod. (15.7) says that Plato was sold by Dionysius in Syracuse itself. Plut. (Dion 5) speaks οf Pollis selling him in Aegina at the instigation of Dionysius but does nοt mention Anniceris, who comes in D.L. (3.20). Olympiod. (V.Ρ. 4) tells the full story but transfers it to Plato’s second visit with the younger Dionysius as instigator. (Full sources in Zeller, 2.1.414 n. 3.) Ιt is possible that the story can be traced back to Aristotle. So Diels thought, because at Physics 199b20 Aristotle chooses as an example of a chance occurrence ‘the stranger who happened to come, paid the ransom and went away’, a note obviously intended for expansion in the lecture-room. (See Ross ad loc. and cf. κατὰ τύχην παρών Ἀννίκερις in D.L.) Taylor (PMW 5 n. 1) counted it against Diels that Simpl. ad 1οc. (p. 384) ‘supposes Aristotle’s allusion is to some situation in a comedy’. But Simpl. is precise: ὡς ὁ παρὰ Μενάνδρῳ Δημέας τὴν Κρατείαν. Apart from the fact that Demeas was no ξένος but Crateia’s father, Aristotle was hardly in a position to allude to Menander’s Misumenos. Simpl. has added his own example: ‘as, οne might say, happens in Menander when Demeas frees Crateia’.
 Εp. 7.326a. This seems to me the natural translation, though it is not the usual one. Foremost among the necessary resources would be the ‘friends and trustworthy co-workers’ just mentioned at 325d.
 Ryle is an exception. See Ρ.’s Ρ. 222ff.
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