Hence it is necessary for a prince wishing to hold his own to know how to do wrong, and to make use of it or not according to necessity.
 Niccolò Machiavelli, The Prince (1532). copy citation

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Author Niccolò Machiavelli
Source The Prince
Topic wrong necessity
Date 1532
Language English
Reference
Note Translated by W. K. Marriott
Weblink http://www.gutenberg.org/files/1232/1232-h/1232-h.htm

Context

“But, it being my intention to write a thing which shall be useful to him who apprehends it, it appears to me more appropriate to follow up the real truth of the matter than the imagination of it; for many have pictured republics and principalities which in fact have never been known or seen, because how one lives is so far distant from how one ought to live, that he who neglects what is done for what ought to be done, sooner effects his ruin than his preservation; for a man who wishes to act entirely up to his professions of virtue soon meets with what destroys him among so much that is evil.
Hence it is necessary for a prince wishing to hold his own to know how to do wrong, and to make use of it or not according to necessity. Therefore, putting on one side imaginary things concerning a prince, and discussing those which are real, I say that all men when they are spoken of, and chiefly princes for being more highly placed, are remarkable for some of those qualities which bring them either blame or praise; and thus it is that one is reputed liberal, another miserly, using a Tuscan term (because an avaricious person in our language is still he who desires to possess by robbery, whilst we call one miserly who deprives himself too much of the use of his own); one is reputed generous, one rapacious; one cruel, one compassionate; one faithless, another faithful; one effeminate and cowardly, another bold and brave; one affable, another haughty; one lascivious, another chaste; one sincere, another cunning; one hard, another easy; one grave, another frivolous; one religious, another unbelieving, and the like.” source

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