How is tim o'brien's chapter "good form" an example of postmodernism

Tim O'Brien's chapter "Good Form" is an example of Postmodernism since it talks about stories themselves. In other words, the work refers to itself.

Postmodernism refers to a broad movement that took place in the mid- to late 20th century across philosophy, the arts, architecture, and criticism and that marked a departure from modernism.

William Timothy "Tim" O'Brien is an American novelist best known for his book The Things They Carried.

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