There is no good and evil, there is only power and those too weak to seek it.

Hearing voices no one else can hear isn't a good sign, even in the wizarding world.

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 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. . . .

What would come, would come...and you would have to meet it, when it did.

Books! And cleverness! There are more important things-friendship and bravery and-oh Harry-be careful!