It’s so difficult to describe [depression] to someone who’s never been there, because it’s not sadness. I know sadness. Sadness is to cry and to feel. But it’s that cold absence of feeling — that really hollowed-out feeling.

Which way did they go, Peeves?" Filch was saying. "Quick, tell me." "Say 'please.'" "Don't mess with me, Peeves, now where did they go?" "Shan't say nothing if you don't say please," said Peeves in his annoying singsong voice. "All right- PLEASE." "NOTHING! Ha haaa! Told you I wouldn't say nothing if you didn't say please! Ha ha! Haaaaaa!" And they heard the sound of Peeves whooshing away and Filch cursing in rage.

Your qualifications, your CV, are not your life, though you will meet many people of my age and older who confuse the two. Life is difficult, and complicated, and beyond anyone's control, and the humility to know that will enable you to survive its vicissitudes.

I never thought I'd hear myself say it, but safety first!

Longbottom, if brains were gold, you'd be poorer than Weasley, and that's saying something.

Neither can live while the other survives, and one of us is about to leave for good.

I don't believe in the kind of magic in my books. But I do believe something very magical can happen when you read a good book.