ABSTRACT Ranjan Ghosh’s The Plastic Turn foregrounds characteristics of plastics that in his view define the modern sensibility—in particular, mutability (plasticity), agglomeration, and the resistance of polymer bonds to breaking down. After exploring interrelated aspects of these three features, the article focuses on plasticity taken alone as the condition of possibility for the program of political and cultural reform inaugurated in Plato’s Republic (written ca. 360 BCE). Just as the minds of young citizens are available to be “molded” by education (the verb plassō describes this process), so too the ideal city can be “fashioned” (also plassō) out of words and imagination, and so as well can the nature and past history of its human population be “fabricated” (plassō yet again). The polysemy and the ideological adaptability of this one Greek word points ahead (as we may say retrospectively) to the fateful docility of plastics—a docility that has allowed them to enter every aspect of our daily lives and, in an ironic turn, saturate our milieu and bodies