Three Master Races

Shwylt Shipsbane remarks, "'I suspect you actually like [Terrans].'" Brechdan Ironrede replies, "'Why, that's no secret...They were magnificent once. They could be again. I would love to see them our willing subjects...Unlikely, of course. They're not that kind of species. We might be forced to exterminate.'"
-Poul Anderson, Young Flandry (New York, 2010), p. 92.

Forced, indeed! You might be forced to reconsider, Brechdan.

Djana (human) is horrified when she overhears Ydwyr (Merseian) discussing her as if she were an animal:

"'A reconditioning. It improved her both physically and mentally.'" (p. 351)

Under Ydwyr's tutelage, she had begun to see him as her father and to imagine a Merseian Christ or even that the Merseians did not need redemption... A reconditioning.

Chuut-Riit (kzin) thinks:

"With a fully-domesticated human species at their disposal, his son's son's sons could even aspire to...no, unthinkable"
-Jerry Pournelle and SM Stirling, "The Children's Hour" IN Larry Niven, Ed., Man-Kzin Wars II (New York, 1991), pp. 133-306 AT p. 155.

I would have preferred if Chuut-Riit had completed that sentence, though. Finally, he sounds exactly like one of Stirling's Draka looking forward to the subordination of the rest of the human race.