Many people believe that fortune controls everything, so that there is no use in trying to act, but fortune controls only half of one's actions, leaving free will to control the other half. Fortune can be compared to a river that floods, destroying everything in its way. But when the weather is good, people can prepare dams and dikes to control the flood. If Italy had such preparations, she would not have suffered so much in the present floods.
Princes are successful one day and ruined the next, with no change in their natures. Two men may use the same method, but only one succeeds; and two men may use different methods, but reach the same goal, all because the circumstances do or do not suit their actions. If a man is successful by acting one way and the circumstances change, he will fail if he does not change his methods. But men are never flexible enough to change, either because their natures will not let them or because they become accustomed to a certain behavior bringing success.
It is better to be bold than timid and cautious, because fortune is a woman, and the man who wants to control her must treat her roughly.
This chapter is perhaps the most pivotal in The Prince, because Machiavelli discusses the relationship of action and fortune in determining the prince's success. Machiavelli uses fortune (fortuna) in at least two senses. In Chapters 7 and 8, Machiavelli contrasts virtù with fortune in the sense of luck or the favor of powerful people. In those chapters, the contrast is between what the prince can control (his own actions) and what he cannot control (the favor of others). In this chapter, fortune refers more to prevailing circumstances and events, which are still things that the prince cannot directly control. Rather than taking the fatalistic view that all events are controlled by destiny and that it is useless to work toward a particular outcome, Machiavelli gives fortune control over only half of human actions, letting free will influence the rest. If free will did not operate, all of a prince's virtù would be for nothing.
Yet Machiavelli struggles with the problem of why one person succeeds and another fails, even though they have employed the same methods, or why totally different methods can arrive at the same outcome. To explain this, he proposes that success comes when virtù is suited to the particular situation a prince finds himself in. Machiavelli envisions fortune as a set of constantly changing circumstances in which particular actions can bring about success or failure. To describe it, he uses one of his few extended metaphors, making fortune a force of nature, like a river that seems uncontrollable, yet can be tamed and directed by human activity. If the Italian princes had made suitable preparations, the "flood" of foreign invasions would not have swept over the open and unprotected country.
Having affirmed the value of free will, Machiavelli limits it by asserting that even though it may be possible to vary one's actions to suit the times, no one ever does. Machiavelli implies that this is because virtù is an inherent, natural quality that the prince cannot change. People act according to their character and cannot change their natures. This line of reasoning brings Machiavelli back to the pessimistic fatalism he rejected at the beginning of the chapter. If a prince cannot change his nature, success depends simply on being lucky enough to have a character suited to the times he lives in.
Fortune was frequently personified in Renaissance art and literature as Fortuna, a female figure who held a turning wheel to symbolize her constant state of change. Fortuna's fickleness is her greatest trait; no sooner are you at the top of her wheel than it turns, and you end up at the bottom. Drawing on this symbolism, Machiavelli closes the chapter by saying that a man who wants to subdue fortune must treat her like the woman she is, and approach her with boldness and roughness. While Machiavelli's metaphor may be offensive to some modern readers, it would not have been shocking in its own day. Even in modern times, the saying "fortune favors the bold" can still be heard.
Julius the warlike pope's remarkable career as a military leader was cut short by his sudden death in 1513.