“When you were straight, evil thoughts and memories came pouring up out of the darkness inside you; buzzing black flies clinging to the insides of your skull.”

“The mind is not a book, to be opened at will and examined at leisure. Thoughts are not etched on the inside of skulls, to be perused by an invader. The mind is a complex and many-layered thing, Potter… or at least, most minds are…”

“Was it love when somebody filled a space in your life that yawned inside you, once they had gone?”

“Prongs rode again last night... You know, Harry, in a way, you did see your father last night... You found him inside yourself.”

“You mustn’t blame yourself for the way the boy’s turned out, Vernon. If there’s something rotten on the inside, there’s nothing anyone can do about it.”

“They don’t need walls and water to keep the prisoners in, not when they’re trapped inside their own heads, incapable of a single cheerful thought. Most go mad within weeks.”

“Sirius — it’s me . . . it’s Peter . . . your friend . . . you wouldn’t . . .”Black kicked out and Pettigrew recoiled.“There’s enough filth on my robes without you touching them,” said Black.”