“Many have stood their ground and faced the darkness when it comes for them. Fewer come for the darkness and force it to face them.”

“Boys," said Hermione Granger, "should not be allowed to love girls without asking them first! This is true in a number of ways and especially when it comes to gluing people to the ceiling!”

“He wanted to write someone and demand a refund on his dark side which clearly ought to have irresistible magical power but had turned out to be defective.”

“...there's something in science like the shine of the Patronus Charm, driving back all sorts of darkness and madness...”

“You will find ambiguity a great ally on your road to power. Give a sign of Slytherin on one day, and contradict it with a sign of Gryffindor the next; and the Slytherins will be enabled to believe what they wish, while the Gryffindors argue themselves into supporting you as well. So long as there is uncertainty, people can believe whatever seems to be to their own advantage. And so long as you appear strong, so long as you appear to be winning, their instincts will tell them that their advantage lies with you. Walk always in the shadow, and light and darkness both will follow.”

“[...] intelligent people only have a certain amount of time (measured in subjective time spent thinking about religion) to become atheists. After a certain point, if you're smart, have spent time thinking about and defending your religion, and still haven't escaped the grip of Dark Side Epistemology, the inside of your mind ends up as an Escher painting.”

“Sometimes Harry thought the deepest split in his personality wasn't anything to do with his dark side; rather it was the divide between the altruistic and forgiving Abstract Reasoning Harry, versus the frustrated and angry Harry In The Moment.”