He uses as an example a warning sign that used to be on all trains in Italy.
The sign had:
Please do not lean out of the window
Prière de ne pas se pencher au dehors
In a nutshell, along his analysis, the Germans being a very disciplined people, they need a direct order: DO NOT lean out of the window!
The English (UK) have the fame of being very polite, so they are asked to: Please, do not lean out of the window.
The French are said to have something that cannot be translated, which is nonchalance so they are told: You are asked not to lean out of the window (which leaves them a sort of free will, they are asked not to do something, but after all it's up to them).
The Italian is a plain statement (actually an obvious one): It is dangerous to lean out of the window.
You cannot tell an Italian to NOT do something (as the effect will be that he/she will attempt it first thing), nor you can tell him/her to do something Please (as the reaction would be: Please who? What do I get if i comply?) so everything is left to common sense (you have been told, but do whatever you see fit).
How would this translate in other places/countries?
I have two propositions for the US :
What about other countries/languages?