Jaropelc, a Russian duke, suborned a Hungarian nobleman to betray Boleslaus, king of Poland, by either killing him or giving the Russians opportunity to do him some notable damage. This man went about it smoothly, devoted himself more than before to the service of this king, and succeeded in becoming one of his council and one of his most trusted men. With these advantages, and adroitly seizing the opportunity offered by his master’s absence, he betrayed to the Russians Wieliczka, a great and rich city, which was entirely sacked by them, with the slaughter not only of its inhabitants of all ages and both sexes, but also of a great number of neighboring nobles assembled there for that purpose. When Jaropelc, sated with his vengeance and wrath—which, however, was not without reason (for Boleslaus had done him great harm and by similar conduct)—and glutted with the fruit of this treachery, came to consider its ugliness naked and by itself, and to look at it with a sane vision no longer troubled by his passion, he began to feel such remorse and revulsion that he had his agent’s eyes put out and his tongue and private parts cut off.

From Montaigne’s Complete Essays, translated by Donald M. Frame, Stanford, California: Stanford University Press, 1958, p. 605.