People don't alter history any more than birds alter the sky, they just make brief patterns in it.
Terry PratchettThat's the Ankh-Morpork instinct, Vimes thought. Run away, and then stop and see if anything interesting is going to happen to other people.
Terry PratchettA Thaum is the basic unit of magical strength. It has been universally established as the amount of magic needed to create one small white pigeon or three normal-sized billiard balls.
Terry Pratchett