"“It’s all right. I worked it out. This is the school, isn’t it? The magic place? The world. Here. And you don’t realize it until you look. Do you know the pictsies think this world is heaven? We just don’t look. You can’t give lessons on witchcraft. Not properly. It’s all about how you are...you, I suppose.” “Nicely said,” said Mistress Weatherwax. “You’re sharp. But there’s magic, too. You’ll pick that up. It don’t take much intelligence, otherwise wizards wouldn’t be able to do it.”"
January 1, 1970
https://en.wikiquote.org/wiki/Discworld