Laudator Temporis Acti

Christopher Pelling, Literary Texts and the Greek Historian (London: Routledge, 2000), p. 123, with note on p. 276:

An American observer, so the story goes, once expressed surprise at the way in which Margaret Thatcher dominated the British cabinet. He was advised to read P.G. Wodehouse on Bertie Wooster and his aunts. Comedy tells. And Dionysius of Syracuse, so another story went, once asked Plato to explain to him the nature of Athenian political life. Plato responded by sending him a work of Aristophanes.¹

1 Life of Aristophanes (Proleg. XXVIII 46–9, p. 135 Koster); Riginos 1976: 176-8.

Here is the Greek, followed by Jeffrey Henderson's translation:

φασὶ δὲ καὶ Πλάτωνα Διονυσίῳ τῷ τυράννῳ βουληθέντι μαθεῖν τὴν Ἀθηναίων πολιτείαν πέμψαι τὴν Αριστοφάνους ποίησιν, [τὴν κατὰ Σωκράτους ἐν Νεφέλαις κατηγορίαν,] καὶ συμβουλεῦσαι τὰ δράματα αὐτοῦ ἀσκηθέντα μαθεῖν αὐτῶν πολιτείαν.

And they say that when Dionysius the tyrant wanted to learn about the polity of the Athenians, Plato sent him the poetry of Ar. [the accusation against Socrates in Clouds] and advised him to study the plays if he would learn their polity.

Riginos = Alice Swift Riginos, Platonica: The Anecdotes Concerning the Life and Writings of Plato (Leiden: E.J. Brill, 1976).