The prince, therefore, who can bring together a strong army can do without building fortresses, while he who has not a strong army ought not to build them, but should carefully strengthen the city wherein he dwells, and keep it well stored with supplies, and its inhabitants well affected, so that he may resist attack till an accord be agreed on, or he be relieved by foreign aid. All other expedients are costly in time of peace, and in war useless.
Whoever carefully weighs all that has now been said will perceive, that the Romans, as they were most prudent in all their other methods, so also showed their wisdom in the measures they took with the men of Latium and Privernum, when, without ever thinking of fortresses, they sought security in bolder and more sagacious courses.
Violent dissensions breaking out in Rome between the commons and the nobles, it appeared to the Veientines and Etruscans that now was their time to deal a fatal blow to the Roman supremacy. Accordingly, they assembled an army and invaded the territories of Rome. The senate sent Caius Manlius and Marcus Fabius to meet them, whose forces encamping close by the Veientines, the latter ceased not to reproach and vilify the Roman name with every sort of taunt and abuse, and so incensed the Romans by their unmeasured insolence that, from being divided they became reconciled, and giving the enemy battle, broke and defeated them. Here, again, we see, what has already been noted, how prone men are to adopt wrong courses, and how often they miss their object when they think to secure it. The Veientines imagined that they could conquer the Romans by attacking them while they were at feud among themselves; but this very attack reunited the Romans and brought ruin on their assailants. For the causes of division in a commonwealth are, for the most part, ease and tranquillity, while the causes of union are fear and war. Wherefore, had the Veientines been wise, the more divided they saw Rome to be, the more should they have sought to avoid war with her, and endeavoured to gain an advantage over her by peaceful arts. And the best way to effect this in a divided city lies in gaining the confidence of both factions, and in mediating between them as arbiter so long as they do not come to blows; but when they resort to open violence, then to render some tardy aid to the weaker side, so as to plunge them deeper in hostilities, wherein both may exhaust their forces without being led by your putting forth an excess of strength to suspect you of a desire to ruin them and remain their master. Where this is well managed, it will almost always happen that you succeed in effecting the object you propose to yourself.