When, because of their fear, they do away secretly with such men, who is left for them to use save the unjust, the incontinent, and the slavish? The unjust are trusted because they are afraid, just as the tyrants are, that someday the cities, becoming free, will become their masters. The incontinent are trusted because they are at liberty for the present, and the slavish because not even they deem themselves worthy to be free. This affliction, then, seems harsh to me: to think some are good men, and yet to be compelled to make use of the others. - Xenophon, Tyrannicus part 5
