those wars in which the Florentines were compelled to take part.  Thus, from the war between John of Anjou and King Ferrando, originated those serious enmities and hatreds which ensued between Ferrando and the Florentines, particularly the house of Medici.  The king complained of a want of assistance during the war, and of the aid afforded to his enemy; and from his anger originated the greatest evils, as will be hereafter seen.  Having, in speaking of external affairs, come down to the year 1463, it will be necessary in order to make our narrative of the contemporaneous domestic transactions clearly understood, to revert to a period several years back.  But first, according to custom, I would offer a few remarks referring to the events about to be narrated, and observe, that those who think a republic may be kept in perfect unity of purpose are greatly deceived.  True it is, that some divisions injure republics, while others are beneficial to them.  When accompanied by factions and parties they are injurious; but when maintained without them they contribute to their prosperity.  The legislator of a republic, since it is impossible to prevent the existence of dissensions, must at least take care to prevent the growth of faction.  It may therefore be observed, that citizens acquire reputation and power in two ways; the one public, the other private.  Influence is acquired publicly by winning a battle, taking possession of a territory, fulfilling the duties of an embassy with care and prudence, or by giving wise counsel attended by a happy result.  Private methods are conferring benefits upon individuals, defending them against the magistrates, supporting them with money, and raising them to undeserved honors; or with public games and entertainments gaining the affection of the populace.  This mode of procedure produces parties and cliques; and in proportion as influence thus acquired is injurious, so is the former beneficial, if quite free from party spirit; because it is founded upon the public good, and not upon private advantage.  And though it is impossible to prevent the existence of inveterate feuds, still if they be without partisans to support them for their own individual benefit, they do not injure a republic, but contribute to its welfare; since none can attain distinction, but as he contributes to her good, and each party prevents the other from infringing her liberties.  The dissensions of Florence were always accompanied by factions, and were therefore always pernicious; and the dominant party only remained united so long as its enemies held it in check.  As soon as the strength of the opposition was annihilated, the government, deprived of the restraining influence of its adversaries, and being subject to no law, fell to pieces.  The party of Cosmo de’ Medici gained the ascendant in 1434; but the depressed party being very numerous, and composed of several very influential persons, fear kept the former united, and restrained their proceedings within the bounds of moderation, so that no violence was committed by them, nor anything done calculated to excite popular dislike.  Consequently, whenever this government required the citizens’ aid to recover or strengthen its influence, the latter were always willing to gratify its wishes; so that from 1434 to 1455, during a period of twenty-one years, the authority of a balia was granted to it six times.