“ Indeed, more frequently have the former reason to fear that the powerful in cities will act unjustly to them either through calumny or violence. But his greatest and absurdest error is that he takes away from exiles freedom of speech. ”
 Plutarch, Moralia (c. 100 AD). copy citation

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“935 For first of all, not to say out all one thinks is not the action of a slave but of a sensible man, in times and matters that require reticence and silence, as Euripides himself has said elsewhere better,
"Be silent where 'tis meet, speak where 'tis safe."
Then as for the follies of one's masters, one has to put up with them just as much in one's own country as in exile. Indeed, more frequently have the former reason to fear that the powerful in cities will act unjustly to them either through calumny or violence. But his greatest and absurdest error is that he takes away from exiles freedom of speech. It is wonderful, if Theodorus had no freedom of speech, that when Lysimachus the king said to him, "Did 391 not your country cast you out because of your character?" replied, "Yes, as Semele cast out Dionysus, when unable to bear him any longer."” source