"‘Brilliant,’ said Hermione. ‘This isn’t magic - it’s logic - a puzzle. A lot of great wizards haven’t got an ounce of logic, they’d be stuck here for ever.’"
Hermione Granger; Harry Potter and the Philosopher’s Stone, Chapter 16 - Through The Trapdoor
This is, in my opinion, a greatly undervalued quote. So often people criticise the absurdity of certain goings-on in the Harry Potter universe. However, J.K. Rowling already trumped you in book one.