"Everyone realizes how praiseworthy it is for a prince to honour his word and to be straightforward rather than crafty in his dealings; none the less contemporary experience shows that princes who have achieved great things have been those who have given their word lightly, who have known how to trick men with their cunning, and who, in the end, have overcome those abiding by honest principles.
You should understand, therefore, that there are two ways of fighting: by law or by force. The first way is natural to men, and the second to beasts. But as the first way often proves inadequate one must needs have recourse to the second. So a prince must understand how to make nice use of the beast and the man. The ancient writers taught princes about this by allegory, when they described how Achilles and many other princes of the ancient world were sent to be brought up by Chiron, the centaur, so that he might train them his way. All the allegory means, in making the teacher half-beast and half-man, is that a prince must know how to act according to the nature of both, and that he cannot survive otherwise."
Extracted from The Penguin Book of Lies, an excellent dip-in book for a rainy day, and when you can't think of a single sensible thing to write on your blog! The original, of course, is from that naughty Niccolò Machiavelli who never told anything but the plain, unvarnished truth and leaves you gasping, and laughing, at his shocking honesty!