At daybreak, the two travelers find themselves on a plain dotted with thirty or forty windmills. Don Quixote is jubilant. "Look yonder, friend Sancho," he cries, "Fortune has provided me with thirty or forty giants to encounter. When they are dead we may claim the lawful spoils of our conquest." The naive squire asks, "What giants?" but Don Quixote, covered with his shield and lance couched, has already spurred Rosinante forward. He drives his weapon into the revolving sail of the first windmill, but the motion breaks the lance and roughly hurls horse and rider a good distance away. "Did I not tell you they are windmills!" cries Sancho, rushing to his aid. Don Quixote says that he is truly unlucky, for the same accursed necromancer who carried away his books and study now deprived him of victory by changing these giants into windmills.
Finally finding a place to rest for the night, Sancho falls into deep sleep while Don Quixote remains wakeful, meditating until dawn on his mistress Dulcinea del Toboso, in imitation of what he has read in books of chivalry. Another adventure presents itself the next morning. Two monks on muleback approach, followed by a carriage, which is followed by a mounted escort and some muleteers. Telling Sancho that these are two black necromancers carrying off some distressed princess, the knight challenges and attacks the first monk. He escapes death by diving from his mule, while his companion flees as fast as his beast can go. Sancho, newly learned in chivalry, eagerly begins to despoil the fallen monk, but the two muleteers prevent this and give him a sound beating as well. Don Quixote is busy at this time presenting himself to the lady in the carriage. Her gentleman-squire, a man from Biscay, takes offense, and the two men begin an epic struggle.
Quickly, with many adventures, Don Quixote is launched on his career of faith as a knight-errant. Sancho is likewise launched, for if he can withstand the adventure of the windmills and still remain attached to his madman master, he can be loyal throughout even more extravagant adventures.
The combat with the windmill is rich in symbolism. It does not matter whether the ponderous machine stands for stultified human institutions that need attacking, or ancient traditions that must be newly questioned, or totalitarian government requiring renewal by revolution, or bureaucracy being attacked by individual demands. What matters is that only a positive act of will is capable of attacking anything, and the success or failure is unimportant. "Thy triumph, my Don Quixote," writes Unamuno, "Was ever a triumph of daring, not of succeeding." Not only is Don Quixote victorious because he dares; he is always spiritually triumphant as well. He has a stoical ability to disregard his physical failures and is willing to follow his adventures after a slight recovery.