Haven’t you got any romance in your soul?’ said Magrat plaintively. ‘No,’ said Granny. 'I ain’t. And stars don’t care what you wish, and magic don’t make things better, and no one doesn’t get burned who sticks their hand in a fire. If you want to amount to anything as a witch, Magrat Garlick, you got to learn three things. What’s real, what’s not real, and what’s the difference.

You're wondering if I really would slit your throat. To tell the truth, I don't know either, but think of the fun we could have finding out.