“Everybody knows it. Wizards are supposed to have beards. It's common knowledge.”
“It's one of those songs that everybody knows, but you are not supposed to do, because everyone does it, only no-one does it, because you're not supposed to do it, because everyone does it....if you follow that....”
“I was there to see beautiful naked women. So was everybody else. It's a common failing.”
“My beard has started growing a beard of its own, and I’m stuck having to take it for a walk.”
“I have know a thousand scamps; but I never met one who considered himself so. Self-knowledge isn't so common.”
“But,' I reminded myself, 'it's common knowledge that life isn't worth living, anyhow.”