Abstract Expressionism marks a pivotal shift into **postmodern thought**, where meaning fractures and formalism reigns. At its core lies Clement Greenberg’s concept of “flatness”—the idea that painting should embrace its true nature as pigment on a two-dimensional surface, not illusion or narrative. By rejecting depth, realism, and traditional representation, Abstract Expressionism dismantles old hierarchies and invites a self-aware, reflexive approach to art. This embrace of surface over substance becomes a stepping stone into postmodernism’s skepticism, ambiguity, and celebration of art as both process and critique.