Why is Miguel de Cervantes’s Don Quixote important in the development of the modern novel?

Miguel de Cervantes’s Don Quixote is widely considered the prototype of the modern novel due to several groundbreaking literary innovations.12

• Heteroglossia: Cervantes introduced a "dazzling assortment of characters" with diverse perspectives and beliefs. This inclusion of multiple voices, a concept termed heteroglossia by critic Mikhail Bakhtin, is essential to the development of the modern novel.13
• Psychological Realism: By moving away from static characterizations, Cervantes created a dynamic interplay between the protagonist and his squire, Sancho Panza. Their evolving relationship and conflicting perceptions of reality established a new standard for psychological depth.2
• Dualistic Worldview: The novel challenges the reader's perception by blurring the lines between fiction and historical truth. Cervantes often paired opposites—such as illusion and reality—to provide philosophical commentary on human existence.42
• Meta-fictional Awareness: In Part II, the characters become aware that their own adventures are being read and discussed, demonstrating an innovative understanding of the cultural and economic impact of literature.3