“ It is meanness everywhere that stops a man's speech, ties and gags his tongue, and forces him to be silent. ”
 Plutarch, Moralia (c. 100 AD). copy citation

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“For as a favourable occasion presented itself he urged the king to attack the enemy, and when after sacrifice he reported that the entrails forbade it, Hannibal chided him and said, "You listen rather to what flesh tells you than to the instruction of a man of experience." Nor does exile deprive geometricians or grammarians of their freedom of speech, or prevent their discussing what they know and have learnt. Why should it then good and worthy men? It is meanness everywhere that stops a man's speech, ties and gags his tongue, and forces him to be silent. But what are the next lines of Euripides?
Jocasta. Hopes feed the hearts of exiles, so they say. Polynices. Hopes have a flattering smile, but still delay. 938
But this is an accusation against folly rather than exile.” source