Long ago, my father and brother emailled me a letter that Napolean had written to his son way back when. I was so affected by it that I still go back to it time after time.
"You are still at an age when one does not realise the perversity of men's hearts: I cannot therefore too strongly recommend you to be prudent and circumspect. Our Italian subjects are more deceitful by nature than the citizens of France. The only way you can keep their respect and serve their happiness is by having no one have your complete confidence and by never telling anyone what you really think of the ministers and high officials of your court. Dissimulation that comes naturally at a maturer age has to be emphasised and inculcated at yours. If you ever find speaking unnecessarily say to yourself, " I have made a mistake" and don’t do it again.
Show respect to the nation you govern and show it all the more as you discover less grounds for it. You will come to see in time that there is little difference between one nation and another...learn to listen and remember that silence is often as effective as a display of knowledge...so long as a prince holds his tongue his power is incalculable: he should never talk unless he knows he is the ablest man in the room.
Don’t trust spies they are trouble than they are worth. The army is one thing you can deal with personally... You must not expose yourself to any sort of affront. If anything of the kind occurs, don’t stand it. Whosoever he may be have him arrested on the spot. Don’t show too much attention to foreigners, there is nothing to gain by this. An ambassador will never speak well of you as it his business to speak ill.. Ambassadors/ ministers of foreign countries are in plain words accredited spies. Don’t show my letter to anyone under any pretext. One last word: Punish dishonesty ruthlessly. The exposure of a dishonest accountant is a victory of the Government...."