“...if you're unhappy whenever other people don't picture you exactly the same way you picture yourself, that's already dooming yourself to always be unhappy. No one ever thinks of us just the same way we think of ourselves.”

“Not every change is an improvement but every improvement is a change; you can't do anything BETTER unless you can manage to do it DIFFERENTLY, you've got to let yourself do better than other people!”

“In a moral dilemma where you lost something either way, making the choice would feel bad either way, so you could temporarily save yourself a little mental pain by refusing to decide. At the cost of not being able to plan anything in advance, and at the cost of incurring a huge bias toward inaction or waiting until too late...”

“And then Harry Potter had launched in to a speech that was inspiring, yet vague. A speech to the effect that Fred and George and Lee had tremendous potential if they could just learn to be weirder. To make people's live surreal, instead of just surprising them with the equivalents of buckets of water propped above doors. (Fred and George had exchanged interested looks, they'd never thought of that one.) Harry Potter had invoked a picture of the prank they'd pulled on Neville - which, Harry had mentioned with some remorse, the Sorting Hat had chewed him out on - but which must have made Neville doubt his own sanity. For Neville it would have felt like being suddendly transported into an alternate universe. The same way everyone else had felt when they'd seen Snape apologize. That was the true power of pranking.”

“Like that's the only reason anyone would ever buy a first-aid kit? Don't take this the wrong way, Professor McGonagall, but what sort of crazy children are you used to dealing with?""Gryffindors," spat Professor McGonagall, the word carrying a freight of bitterness and despair that fell like an eternal curse on all youthful heroism and high spirits.”

“Do not think that fairness to all sides means balancing yourself evenly between positions; truth is not handed out in equal portions before the start of a debate.”

“‎If you regard evidence as a constraint and seek to free yourself, you sell yourself into the chains of your whims. For you cannot make a true map of a city by sitting in your bedroom with your eyes shut and drawing lines upon paper according to impulse.”