Niccolo Machiavelli is revered as the founder of modern political philosophy. He was considered a "realist" because he concerned himself only with the political situations that actually arose in reality; where as previous philosophers were concerned largely with the theoretical politics of an "idealist" prefect society. Machiavelli presents Medici with a sort of guidebook of successful political practices. Machiavelli goes against Platonic philosophy. Whereas Plato believed that human kind was virtuous by nature, with evil men being but a small fraction of the species, Machiavelli felt that it was virtuous who were a minority in a world of evil men. Machiavelli goes on to say that the evil majority would generally overcome the virtuous few. Thus it is the duty of rulers to safeguard themselves from the evil men by committing non-virtuous acts. Rather than contemplating how one might change human nature, Machiavelli was more interested in using it to serve his own ends. Machiavelli begins by saying that the most difficult thing for a ruler to do is to acquire a new kingdom. This may be accomplished one of two ways, "either by the arms of others or by one's own, either by fortune or virtue." What he means by the "arms of others" and "fortune" is monarchs that inherit their kingdoms. When Machiavelli refers to using one's own arms or "virtue," he is in fact equating virtue with force. By advocating the use of force, Machiavelli became the first political thinker to suggest power politics. According to Machiavelli, acquiring a kingdom by force is perfectly all right, because the desired end justifies any means necessary to achieve it. He does however instruct Medici as to "the good and bad use of cruelties." By this, Machiavelli is referring to both the effective and non-effective uses of force. Machiavelli states that "Good use is when is when they [acts of cruelty] are perpetrated all at once and subsequently not repeated.