The English have instructions everywhere.

"Keep right on the escalators."

"Do not use the locked gates. Please proceed to the entrance on the right."

No one has ever persuaded the English that the best way to get people to do things might not be to command them. It's not just the ubiquitous officious signs that sound like a Telegraph reader holding a clipboard. Every single advertisement contains a command.

"BUY IT NOW!" "GET YOUR HANDS ON IT." "BE THERE!!"

Most of it is useless.

"Do not violently assault Underground staff."

That's going to be great, isn't it? You can just imagine some chav about to bop a station warden on the nose, and then thinking "Oh, blimey, there was that sign saying I shouldn't hit these geezers. Orright sunshine, on yer way then."

The July attacks have sent sign-makers into frenzies of new commands.

"Terrorist activities are strictly prohibited. Offenders are liable to severe penalties. You must not commit terrorist actions on London Underground Services. If you are a terrorist, please report immediately to London Underground authorities. Thank you for choosing to travel with London Underground."