How does this piece demonstrate chivalry?

Delusion is another major thematic concern of the novel. The books of chivalry have left Don Quixote incapable of seeing "reality." Many of Quixote's deluded interpretations are rather ironic. Perhaps Quixote is merely innocent and naïve when he mistakes the two prostitutes for damsels. Later in Book I, Quixote will argue that the idealization of a person makes this person ideal. True to the chivalric standard, Quixote idealizes women with little justification or provocation. Don Quixote is definitely "in the pursuit of ideals," old chivalric ideals that were no longer the mode in his society. At the same time, the characterization of Quixote is rather complex. For an innocent, Quixote certainly causes a good amount of damage‹if Quixote is a hero, he is not an ordinary hero. Andres suffers far more than he would have, had Don Quixote never 'come to the rescue.' Throughout Book I, Don Quixote reveals himself to be both impatient and violent.

Don Quixote wants to be a knight. Since knights had allegiance to women, king, and God, the Don and his sidekick try to participate in such battles that defend his country and his king. Even though Dulcinea is nothing more than a simple bar maid, he defends her as if she is the knight's lady who deserves to be defended.