The leader should know how to enter into evil when necessity commands.

All courses of action are risky, so prudence is not in avoiding danger (it's impossible), but calculating risk and acting decisively. Make mistakes of ambition and not mistakes of sloth. Develop the strength to do bold things, not the strength to suffer.

War brings out thieves and peace hangs them.

A wise ruler ought never to keep faith when by doing so it would be against his interests.

Politics have no relation to morals.

For he who innovates will have for his enemies all those who are well off under the existing order of things, and only lukewarm supporters in those who might be better off under the new.

To keep your actions and your plans secret always has been a very good thing . .. Marcus Crassus said to one who asked him when he was going to move the army: 'Do you believe that you will be the only one not to hear the trumpet?