A Connecticut Yankee in King Arthurs Court by Mark Twain Chapter 30 Page 6

He could see only one side of it. He was born so, educated so, his veins were full of ancestral blood that was rotten with this sort of unconscious brutality, brought down by inheritance from a long procession of hearts that had each done its share toward poisoning the stream. To imprison these men without proof, and starve their kindred, was no harm, for they were merely peasants and subject to the will and pleasure of their lord, no matter what fearful form it might take; but for these men to break out of unjust captivity was insult and outrage, and a thing not to be countenanced by any conscientious person who knew his duty to his sacred caste.

I worked more than half an hour before I got him to change the subject — and even then an outside matter did it for me.