Love serves as the novel's central theme, influencing the actions of knight-errantry. In several genuine adventures, such as those of Dorotea and Cardenio or Basilio and Quiteria, where coerced marriages are questioned, love ultimately prevails: "true love cannot be divided, but must be free and uninhibited." Each of these tales offers insights into the nature of love. These insights are particularly highlighted in "The Tale of Ill-Advised Curiosity." Love also leads to forgiveness, even in extreme cases like murder, as demonstrated by Claudia and Don Vicente.

The theme of love seldom involves Don Quixote directly. Although he praises the virtues of true love and works to avert conflicts, as seen in the situation with Camacho the Rich, the theme of love is rooted in reality, and Don Quixote remains detached from the many reunions throughout the story. For example, during the dramatic reunion of Luscinda and Don Fernando, Don Quixote is asleep and dreaming.

"There are two roads … by which men can travel and reach wealth and honor: one is the way of letters, the other the way of arms." Don Quixote has chosen the path of arms. He strongly believes that fighting for justice is as important as anything else. He does not support modern warfare; instead, he prefers the ancient, chivalric duels that involve one-on-one combat.

Despite this, there is a yearning for peace. Through his words and actions, Don Quixote reveals a preference for the serene Arcadian life. He fervently defends the art of poetry and ultimately desires to live the simple life of a shepherd, without any mention of seeking revenge for his honor. Sancho, too, is inclined towards this peaceful option when he questions the need for hunting. The Duke explains that rulers hunt to keep their skills sharp, as "chase is the image of war." However, Sancho wonders if it is wasteful to always be engaged in war, "killing an animal that has done no harm to anyone." This sentiment could also apply to the other victims of Don Quixote's efforts to revive knight-errantry.

In the life of a knight-errant, the topic of fear often arises among fans, admirers, and squires. Sancho frequently worries about his safety and that of his master. However, as he admits to his wife, this lifestyle brings him joy. Whether he's climbing an oak tree or running away, Sancho finds happiness simply in being part of the adventure. Both Don Quixote and Sancho believe that attempting something and possibly failing is preferable to not trying at all.

At the height of his skills, shortly after defeating the Knight of the Mirrors, Don Quixote encounters the ultimate bravery test. Faced with this challenge, he reveals a deep insight about fear: "Fear ….. will make [danger] seem bigger by half." He then confronts and defeats the lion. Everyone is amazed by this achievement, although the narrator downplays its importance. Don Quixote's willingness to face his fears is his true triumph.

Don Quixote becomes so immersed in the idea of knighthood that he loses touch with his identity. His descent into irrationality reflects what happens when someone becomes obsessed with a singular notion. He tells his niece, "if these knightly thoughts did not monopolize all my faculties, there would be nothing I could not do.…"

Despite his apparent madness, Don Quixote never completely loses his sanity; he simply pushes his imagination to its limits. This is a conscious choice, "and that is where the subtleness of my plan comes in. A knight-errant who goes mad for a good reason deserves no credit; the whole point consists in going crazy without cause." Essentially, if knighthood were still popular, Don Quixote wouldn't be remarkable. By reviving chivalry, he seeks to achieve fame.

The core of Don Quixote's mission is to transform his dreams into reality. Experiencing such a fantasy, even for a moment, is more than most hidalgos could claim. Unwittingly, his friends assist in bringing his dream to life more effectively than he could have anticipated. Everyone benefits, for "what the world needed most of all was plenty of knights-errant," and by engaging in his fantasy, his friends help rekindle the traditions of knighthood.

Indeed, their indulgence—their participation in the fantasy—brings Don Quixote's dream to fruition and "astonished [him], and for the first time he felt thoroughly convinced that he was a knight-errant in fact and not in imagination." Tragically, Don Quixote's madness serves as the only way for adults to partake in play within the serious environment of Spain's Golden Age.