Rawson writes: 'In this dialogue, Plato imagines Meno encountering Socrates shortly before that disastrous Persian adventure, when he has not yet proved himself to be the “scoundrel” and “tyrant” that Socrates suspects and Xenophon later confirms. According to Xenophon, when Cyrus was killed and his other commanders were quickly beheaded by the King’s men, Meno was separated and tortured at length before being killed, because of his special treachery (see Xenophon’s Anabasis II, 6)'
But this cannot be right. Meno did not betray the Persians, he betrayed the Greeks, notably Clearchus, the unelected but deeply respected leader of the Greek mercenaries, and the other generals who went with him to the tent of Tissaphernes, the leader of the Persians. And the Persians appreciated it, delighted in it, and presented it to the Greeks in the best possible light.
Xenophon writes that after the generals had been seized in the tent of Tissaphernes and the captains butchered in front of it 'some of the barbarian horsemen rode about over the plain and killed every Greek they met, whether slave or free man. And the Greeks wondered at this riding about, as they saw it from their camp, and were puzzled to know what the horsemen were doing, until Nicarchus the Arcadian reached the camp in flight, wounded in his belly and holding his bowels in his hand, and told all that has happened. Thereupon the Greeks, one and all, ran to their arms, panic-stricken and believing that the enemy would come at once against the camp.' (Anabasis II, v, 32-34)
But not all of the Persians came, only their messengers. 'As soon as they came near, they directed whatever Greek general or captain there might be to come forward, in order that they might deliver the message from the King. After this two generals went from the Greek lines and with them Xenophon the Athenian, who wished to know the fate of Proxenus. And when the Greeks got within hearing distance, Ariaeus said: "Clearchus, men of Greece, inasmuch as he was shown to be perjuring himself and violating the truce, had received his deserts and is dead, but Proxenus and Menon, because they gave information about his plotting, are held in high honour. For yourselves, the king demands his arms; for he says they belong to him, since they belonged to Cyrus, his slave." To this the Greeks replied as follows, Cleanor the Orchomenian acting as spokesman: "Ariaeus, you basest of men, and all you others who were friends of Cyrus, are you not ashamed, either before gods or men, that, after giving us your oaths to count the same people friends and foes as we did, you have betrayed us, joining hands with Tissaphernes, the most godless and villainous man, and that you have not only destroyed the very men to whom you were then giving oath, but have betrayed the rest of us and are come with our enemies against us?" And Ariaeus said: "But it was shown long ago Clearchus was plotting against Tissaphernes and Orontas and all of us who were with them." Upon this Xenophon spoke as follows: "Well, then, if Clearchus was really transgressing the truce in violation of his oaths, he has his deserts, for it is right that perjurers should perish; but as to Proxenus and Meno, since they are your benefactors and our generals, send them hither, for it is clear that, being friends of both parties, they will endeavour to give both you and ourselves the best advice." To this the barbarians made no answer, but, after talking for a long time with one another, they departed.' (Anabasis II, v, 32-34)
Let me end this piece by pointing to the significance of all these events concerning the dating of the Meno.
But first, some more of Diogenes Laertius. In his 'Life of Xenophon' he says that Xenophon 'took part in the expedition of Cyrus in the archonship of Xenaenetus in the year before the death of Socrates.' (II 55)
This means that the whole of Greece knew about Meno's heinous betrayal before the death of Socrates. And so I must ask, how could Plato write the Meno after the death of Socrates?