The sign, which says: "Do not, under any circumstances, open...

The sign, which says: "Do not, under any circumstances, open this door!" - Of course, I've read it. Why do you think I want it opened?.. To see why they wanted it shut, of course. This exchange contains almost all you need to know about human civilization. At least, those bits of it that are now under the sea, fenced off or still smoking.