I am wondering how Postmodernism techniques are employed in this story as well as what is meant by "Postmodern' in writing. 

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Ashley Kannan eNotes educator| Certified Educator

The idea of "Postmodern" writing is to develop a new way of what the writing medium can represent.  Postmodern writing thrives on being able to develop new forms of written expression that break from the traditional narrative structure.  For the Postmodern writer, deconstruction is the most important element.  This deconstruction results in a new vision of writing that can challenge preconceived notions of what defines "writing."  Simply put, Postmodern writing techniques seek to change what was once previously understood about writing into something new.

Kincaid's story features some of these techniques in its postmodern style.  One such example would be how the story is really just a speech, and not a formalized story with a definite structure.  Kincaid's work is more akin to a " type of lyric poetry called the dramatic monologue than it is like most short prose fiction."  This is an example of a Postmodern writing technique because it challenges what the "story" should look like in form.  Another example of a postmodern writing style is the narrative.  Exactly who is speaking and where their relationship exists is thrown into question, another example of the Postmodern deconstruction writing technique revealing itself:

...the entire section could be the daughter's own internal monologue. What if the daughter is simply imagining this oracular, maternal discourse, extrapolating certain worries expressed by the mother in day-to-day asides?

Absolute clarity is absent because this does not necessarily exist in the Postmodern construction of reality.  This technique plays with point of view and temporality, ensuring that time and focus are challenged in a style that is deconstructing reality in order to illuminate a new aspect of it.