The Prince is a slim volume of advice for rulers, eminently quotable, eminently misunderstandable. My translation, which dates to 1910, could use some footnotes, since Machiavelli assumes a level of familiarity with Renaissance Italian politics which I lack, but the principles are firm. The true base of support for a ruler is in the people. Beware of allies and mercenaries, for their objectives are not your own. Cultivate a good reputation, but be willing to cast aside a bargain or social norm the moment it does not benefit you. The sense that rulership is fickle, and only through continued practice and contact with the ruled, comes through again and again.

Although apparently Machiavelli got everything about warfare wrong, this is a book of sound advice for anyone who wishes to gain a little space in the world.