Therefore, a prudent ruler ought not to keep faith when by so doing it would be against his interest, and when the reasons which made him bind himself no longer exist. If men were all good, this precept would not be a good one; but as they are bad, and would not observe their faith with you, so you are not bound to keep faith with them.
Niccolo MachiavelliWe must bear in mind, then, that there is nothing more difficult and dangerous, or more doubtful of success, than an attempt to introduce a new order of things in any state. For the innovator has for enemies all those who derived advantages from the old order of things, whilst those who expect to be benefited by the new institutions will be but lukewarm defenders.
Niccolo MachiavelliThere is nothing more difficult to plan, more doubtful of success, nor more dangerous to manage than the creation of a new order of things..... Whenever his enemies have occasion to attack the innovator they do so with the passion of partisans, while the others defend him sluggishly so that the innovator and his party alike are vulnerable.
Niccolo MachiavelliOne can generally say this about men: that they are ungrateful, fickle, simulators and deceivers, avoiders of danger, greedy for gain; and while you work for their good they are completely yours, offering you their blood, their property, their lives, and their sons when danger is far away; but when it comes nearer to you, they turn away.
Niccolo Machiavelli