LitCharts assigns a color and icon to each theme in Don Quixote, which you can use to track the themes throughout the work.
Truth and Lies
Literature, Realism, and Idealism
Madness and Sanity
Intention and Consequence
Self-Invention, Class Identity, and Social Change
Summary
Analysis
Don Quixote continues the comparison. He says that arms could not exist without letters, because wars are subject to laws, and letters could not exist without arms, because soldiers must enforce the law. He also says that even if the suffering experienced by men of arts and letters is comparable, the rewards of soldierly are far smaller, so it must be nobler. Don Quixote talks so much that he forgets to eat anything. Soon the table is cleared and everyone asks the new guest to tell his story.
For all his dreaminess, Quixote displays a very practical mindset. He says that the purpose of letters (this includes poetry, history, any kind of writing) is to write laws and direct wars – not create beauty. His idealism, too, is meant to serve a practical purpose, to change the world in tangible ways. Beauty is only a small part of that change.