Postmodern culture denies the reality of general categories and collective identities.

Evidence

Contemporary thought and culture are in this sense profoundly nominalist (to expand a diagnosis Adorno made about the tendencies of modern art), Postmodernism more thoroughly so than anything that preceded it. — Fredric Jameson, Postmodernism, or, The Cultural Logic…, 427

Categorization

• DEFINE: Nominalism here = denial that transcendents (classes, isms, collectives) have real status beyond empirical individuals.
• XREF: Ties to reader’s goal of explaining pastiche vs parody — the denial of the transcendent category parallels the flattening of historical depth.