Danger: There’s an Obvious Danger Here!
by Chris MacDonald
This one is fun. It points out something terribly obvious — namely that there’s a very large hole in the street, maybe 10 feet wide and 20 feet long and 12 feet deep, and then adds the strikingly obvious fact that this giant hole constitutes a danger to pedestrians.
Oh, and note not one but two layers of fence between pedestrians and the dangerous, deep hole.
Interestingly, the normative conclusion — “stay away” — is left implicit.
Normative Signs: The Poetry of "Ought" 
Aaah! But the sign-maker is distinctly unpatronising. She is saying “here is a deep hole; it represents a danger in that one might by accident fall in this hole and injure onesself. However, you the reader might be someone who likes and even specialises in jumping into deep holes. For you, I am merely informing you of its existence”