The Prince by Niccolò Machiavelli, ca. 1515

Chapter XVIII -- Concerning the way in which princes should keep their faith

Every one admits how praiseworthy it is in a prince to keep faith, and to live with integrity and not by cleverness. Nevertheless, our experience has been that those princes who have done great things have little respected being true to their word, and instead have known how to get around the intellect of men by cleverness, and in the end have overcome those who have relied on their word.

You must know there are two kinds of conflict: the one by the law, the other by force; the first method is proper to men, the second to beasts. Since because the first is frequently not enough, it is necessary to have recourse to the second. Therefore, it is necessary for a prince to understand how to become like both the beast and the man.

Ancient writers have taught this to princes, such as when they describe how Achilles and many other princes of old were given to the Centaur Chiron to nurse, who brought them up in his discipline; which means that they had for a teacher one who was half beast and half man. Likewise, it is necessary for a prince to know how to make use of both natures, and that one without the other is cannot endure.

A prince, therefore, being compelled to adopt the beast, ought to choose both the fox and the lion: because the lion cannot defend himself against snares and the fox cannot defend himself against wolves. Therefore, it is necessary to be a fox to discover the snares and a lion to terrify the wolves. Those who rely simply on the lion do not understand what they are about.

Indeed, a wise lord cannot, nor ought he to, keep his word when such behavior may be turned against him, and when the reasons that caused him to pledge his word no longer exist. If men were entirely good, this precept would not hold; but because men are bad, and will not keep faith with you, you too must do likewise.

Nor will a prince ever lack legitimate reasons to break his word. Concerning this reality, endless modern examples could be given, showing how many treaties and engagements have been made void and of no effect through the faithlessness of princes. That prince who has known best how to employ the fox has succeeded best.
But it is necessary to know how to disguise this characteristic, and to be a great pretender and dissembler. Men are so simple, and so subject to present necessities, that he who seeks to deceive will always find many others who will allow themselves to be deceived.

One recent example I cannot pass over in silence. Pope Alexander VI did nothing else but deceive men, nor ever thought of doing otherwise, and he always found victims. There never was a man who had greater power in promising, or who with greater oaths would promise a thing, yet would keep his promise less; nevertheless, his deceits always succeeded according to his wishes, because he well understood this characteristic of mankind.

Therefore, it is unnecessary for a prince to have all the good qualities I have enumerated, while it is most necessary to appear to have them. And I shall dare to say this also: that to have them and always to observe them is injurious, and that to appear to have them is useful. Appear to be merciful, faithful, humane, religious, upright, but have a mind so framed that should you need to, you may be able to change to the opposite.

And you have to understand this, that a prince, especially a new one, cannot observe all those things for which men are honored, being often forced to act contrary to fidelity, friendship, humanity, and religion in order to maintain the state. It is necessary for him to have a mind ready to turn itself accordingly as the winds and variations of fortune force it. As I have said above, if a prince can avoid diverging from the good, he should not do so, but, if compelled, then he must know how to set about it.

For this reason a prince ought to take care that he never lets anything slip from his lips that does not reflect the above-named five qualities. Thus he will appear to anyone who sees and hears him as fully merciful, faithful, humane, upright, and religious. There is nothing more necessary than to appear to have than this last quality of seeming religious, inasmuch as men judge generally more by the eye than by the hand…. Every one sees what you appear to be, few really know what you are, and those few dare not oppose themselves to the opinion of the many….

For that reason, should a prince have the credit of conquering and holding his state, people will always consider that his methods were honest, and everyone will praise him; because the common people always accept what a thing seems to be and by what comes of it….

One prince of the present time, whom it is not well to name*, never preaches anything else but peace and good faith, and to both he is most hostile. If he had kept either, he would have deprived himself of reputation and kingdom many a time.

*Perhaps Ferdinand of Aragon, King of Spain.

Adapted from the translation of W. K. Marriott, for an example see here.