According to the text, why do nursing authors often blur the boundaries between postmodernism and post-structuralism?

Nursing authors often blur postmodernism and post-structuralism because the overlap between the two movements is evident and the shared focus is on how these 'post'(s) depart from and challenge earlier Western ideas and practices. Distinctions between the two rarely enter nursing literature, since nurses commonly draw on a mix of 'postmodern' writers, with Foucault chief among them, so the terms are often used nearly interchangeably.

The text explains that blurred boundaries between the two 'isms' seem acceptable not only to nurses but also to scholars in the humanities. For example, short introductions to postmodernism and post-structuralism both address the same key figures and concepts, such as Althusser's ideology, Barthes's death of the Author, Derrida's deconstruction, Foucault's discourse, Lyotard's grand narratives, and Saussure's linguistics, showing a clear overlap. Rather than trying to fully separate the movements, nursing authors and others concentrate on what is most important: how postmodernism and post-structuralism depart from and challenge earlier Western intellectual and material practices, opening up new understandings across politics, culture, literature, ethics, science, education, and health. Although humanities literature on continental philosophy usually differentiates between postmodern and post-structural theory, those distinctions rarely enter nursing literature, and nurses commonly draw on a mix of 'postmodern' writers, with Foucault chief among them. For this reason, the author uses the terms postmodern theory and post-structural theory nearly interchangeably unless the subject demands a clear separation.