And here one must not that hatred is acquired just as much by means of good actions as by bad ones; and so, as I said above, if a prince wishes to maintain the state, he is often obliged not to be good; because whenever that group which you believe you need to support you is corrupted, whether it be the common people, the soldiers, or the nobles, it is to your advantage to follow their inclinations in order to satisfy them; and then good actions are your enemy.
Niccolo MachiavelliA prince ought to have no other aim or thought, nor select anything else for his study, than war and its rules and discipline; for this is the sole art that belongs to him who rules, and it is of such force that it not only upholds those who are born princes, but it often enables men to rise from a private station to that rank. And, on the contrary, it is seen that when princes have thought more of ease than of arms they have lost their states. And the first cause of your losing it is to neglect this art; and what enables you to acquire a state is to be master of the art.
Niccolo MachiavelliSome princes, so as to hold securely the state, have disarmed their subjects, others have kept their subject towns distracted by factions...Our forefathers, and those who were reckoned wise, were accustomed to say that it was necessary to hold Pistoia [an Italian city] by factions and Pisa by fortress, and with this idea they fostered quarrels in some of their tributary towns so as to keep possession of them the more easily.
Niccolo Machiavelli