344 HISTORY OF GREECE. Zeno published a treatise to maintain the thesis above described, which he also upheld by personal conversations and discussions, in a manner doubtless far more efficacious than his writino 1 ; the O * oral teaching of these early philosophers being their really im- pressive manifestation. His subtle dialectic arguments were not only sufficient to occupy all the philosophers of antiquity, in con- futing them more or less successfully, but have even descended to modern times as a fire not yet extinguished. 1 The great effect produced among the speculative minds of Greece by his writing and conversation, is attested both by Plato and Aristotle. He visited Athens, gave instruction to some eminent Athenians, for high pay, and is said to have conversed both with Perikles and with Sokrates, at a time when the latter was very young ; probably between 450-440 B.C. 2 1 The reader will see this in Bayle's Dictionary, article, Zeno of Elea. Simplicius (in his commentary on Aristot. Physic, p. 255) says that Zeno first composed written dialogues, which cannot be believed without more certain evidence. He also particularizes a puzzling question addressed by Zeno to Protagoras. See Brandis, Gesch. der Griech. Rom. Philos. i, p. 409. Zeno Idiov fiev oidev efetfero (sc. nepl ruv ITUVTUV ), 6ir)nopr]ae 61 irepl TOVTUV tiri Trfatov, Plutarch, ap. Eusebium, Prsepar. Evangel, i, 23, D 2 Compare Plutarch, Perikles, c. 3: Plato, Parmenide's, pp. 126, 127; Plato, Alkibiad. i. ch. 14, p. 119, A. That Sokrates had in his youth conversed with Parmenides, whea the latter was an old man, is stated by Plato more than once, over and above his dialogue called Parmenides, which professes to give a conversation betweei the two, as well as with Zeno. I agree with Mr. Fynes Clinton, Brandis. and Karsten, in thinking that this is better evidence, about the date of Par- menides than any of the vague indications which appear to contradict it, in Diogenes Laertius and elsewhere. But it will be hardly proper to place the conversation between Parmenides and Sokfates as Mr. Clinton places it, Fast. H. vol. ii, App. c. 21, p. 364 at a time when Sokrates was only fifteen years of age. The ideas which the ancients had about youthful propriety, would not permit him to take part in conversation with an emi- nent philosopher at so early an age as fifteen, when he would not yet bo entered on the roll of citizens, or be qualified for the smallest function, military or civil. I cannot but think that Sokrates must have been more than twenty years of age when he thus conversed with Parmenides. Sokrates was born in 469 B.C. (perhaps 468 B.C.) ; he would therefore be twenty years of age in 449 : assuming the visit of Parmenides to Athens to have been in 448 B.C., since he was then sixty-five years of age, he would be born in 513 B.C. It is objected that, if this date be admitted, Parmenide*
