The idea that we could have a child who escapes from the confines of the adult world and goes somewhere where he has power, both literally and metaphorically, really appealed to me.

Harry, suffering like this proves you are still a man! This pain is part of being human —” “THEN — I — DON’T — WANT — TO — BE — HUMAN!” Harry roared.

Authority figures always attract trouble

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.

I will not calm down!

That wand’s more trouble than it’s worth,” said Harry. “And quite honestly,” he turned away from the painted portraits, thinking now only of the four-poster bed lying waiting for him in Gryffindor Tower, and wondering whether Kreacher might bring him a sandwich there, “I’ve had enough trouble for a lifetime.

I won't say 'never,' but I have no plans to write an eighth book.