Snape looked horrified. 'You have kept him alive so that he can die at the right moment?''Don't look shocked, Severus. How many men and women have you watched die?''Lately, only those whom I could not save', said Snape.

Potter is mocked by a faculty member for the idea that there is evil in the world from which even children need to learn to defend themselves by the actual practice of doing so rather than familiarity with theory.

But other hordes would come, and other false prophets. Our feeble efforts to ameliorate man__ lot would be but vaguely continued by our successors; the seeds of error and of ruin contained even in what is good would, on the contrary, increase to monstrous proportions in the course of centuries. A world wearied of us would seek other masters; what had seemed to us wise would be pointless for them, what we had found beautiful they would abominate. Like the initiate to Mithraism the human race has need, perhaps, of a periodical bloodbath and descent into the grave. I could see the return of barbaric codes, of implacable gods, of unquestioned despotism of savage chieftains, a world broken up into enemy states and eternally prey to insecurity. Other sentinels menaced by arrows would patrol the walls of future cities; the stupid, cruel, and obscene game would go on, and the human species in growing older would doubtless add new refinements of horror. Our epoch, the faults and limitations of which I knew better than anyone else would perhaps be considered one day, by contrast, as one of the golden ages of man.

It was important, Dumbledore said, to fight, and fight again, and keep fighting, for only then could evil be kept at bay, though never quite eradicated. . . .

I know [Umbridge] by reputation and I'm sure she's no Death Eater-""She's foul enough to be one...""Yes, but the world isn't split into good people and Death Eaters.

It is impossible to manufacture or imitate love.