Among the eminent examples of Italian founders who rose to princely power by their own ability or by availing themselves of the advantages which fortune put within their reach, Machiavelli selects Francesco Sforza and Cesare Borgia.  The former is a notable instance of success achieved by pure virtu:  ’Francesco, by using the right means, and by his own singular ability, raised himself from the rank of a private man to the Duchy of Milan, and maintained with ease the mastery he had acquired with infinite pains.’  Cesare, on the other hand, illustrates both the strength and the weakness of fortuna:  ’he acquired his dominion by the aid derived from his father’s position, and when he lost that he also lost his power, notwithstanding that he used every endeavor and did all that a prudent and able man ought to do in order to plant himself firmly in those states which the arms and fortune of others had placed at his disposal.’  It is not necessary to dwell upon the career of Francesco Sforza.  Not he but Cesare Borgia is Machiavelli’s hero in this treatise, the example from which he deduces lessons both of imitation and avoidance for the benefit of Lorenzo de’ Medici.  Lorenzo, it must be remembered, like Cesare, would have the fortunes of the Church to start with in that career of ambition to which Machiavelli incites him.  Unlike Francesco Sforza, he was no mere soldier of adventure, but a prince, born in the purple, and bound to make use of those undefined advantages which he derived from his position in Florence and from the countenance of his uncle, the Pope.  The Duke Valentino, therefore, who is at one and the same time Machiavelli’s ideal of prudence and courage in the conduct of affairs, and also his chief instance of the instability of fortune, supplies the philosopher with all he needed for the guidance of his princely pupil.  With the Duke Valentino Machiavelli had conversed on terms of private intimacy, and there is no doubt that his imagination had been dazzled by the brilliant intellectual abilities of this consummate rogue.  Dispatched in 1502 by the Florentine Republic to watch the operations of Cesare at Imola, with secret instructions to offer the Duke false promises in the hope of eliciting information that could be relied upon, Machiavelli had enjoyed the rare pleasure of a game at political ecarte with the subtlest and most unscrupulous diplomatist of his age.  He had witnessed his terrible yet beneficial administration of Romagna.  He had been present at his murder of the chiefs of the Orsini faction at Sinigaglia.  Cesare had confided to him, or had pretended to confide, his schemes of personal ambition, as well as the motives and the measures of his secret policy.  On the day of the election of Pope Julius II. he had laid bare the whole of his past history before the Florentine secretary, and had pointed out the single weakness of which he felt himself to have been guilty.  In these trials of skill and this exchange of confidence it is impossible