Final answer:
Don Quixote's belief that defeated knights must martyr themselves is shown through his dedication to endure hardships like forgoing food and sleep, reflecting his chivalric ideals and the romantic yet impractical notions of chivalry in Cervantes' time.
Step-by-step explanation:
In Miguel de Cervantes' classic novel Don Quixote, the titular character is portrayed as a knight who adheres to a chivalric code, which includes the belief that defeated knights ought to punish themselves with acts reminiscent of martyrdom, such as abstaining from food and sleep. This behavior exemplifies the knight's dedication and honor, even in the face of defeat. The concept of self-punishment for defeated knights is communicated through Quixote's various misadventures, reflecting his commitment to the chivalric ideals despite the often-comical outcomes of his actions.
The author details Don Quixote's notions of self-punishment and martyrdom in various parts of the text. Often, the protagonist is determined to endure hardships, be it fasting or vigil, to prove his valor or in penance for his perceived failures. These actions not only demonstrate Quixote's unwavering dedication to the chivalric code but also serve as a broader commentary on the romantic and often impractical ideals of chivalry that were prevalent during Cervantes' era.
While the text suggests Quixote's insistence on self-punishment, the exact methods by which he intends to enforce this upon defeated knights, including himself, are more implied through his actions and the way he carries himself after defeat, rather than explicitly stated in the form of a doctrine or set of rules.