Sheet of notepaper with the words "Quick Notes" in a handwriting font.

‘Books are the best weapon in the world.’

“You want weapons? We’re in a library. Books are the best weapon in the world. This room’s the greatest arsenal we could have. Arm yourself!” – Doctor Who, Ten, “Tooth and Claw,” S2.

I did have to look up which episode it was from, but you’ll just have to take my word for it that I remembered the quote.