Don Quixote, the protagonist of Cervantes' novel, spent a restless night consumed by thoughts of his beloved Dulcinea. His sleeplessness was inspired by the romantic ideals he had read about in stories of chivalrous knights, who often sacrificed sleep to honor their ladies. This reflects Quixote's deep commitment to his own idealism and chivalry.
His unwavering focus on Dulcinea symbolizes the transformative power of love and the lengths to which one will go in the name of romance and knighthood. Quixote's experience reveals how literature influences our thoughts and actions, urging him to emulate the quests of knights from his beloved tales, even in the solitude of night.