The Perestroika movement recently reopened longstanding debates about the scholarly and political implications of orienting political science research around a scientific ideal derived from the natural sciences. Many Perestroikans, like earlier critics of "naturalized" political science, turned to ontology, opposing the political world to the natural world to espouse what I call a two-sciences settlement: a separate-but-equal arrangement in which political science and natural science would each operate according to distinct methodological imperatives dictated by their distinctive objects. In this article, I critically appraise this divided settlement and the two-worlds ontology that underwrites it. I recover an alternative, less dualistic vision of politics and nature from Giambattisa Vico, challenging received views of him as an early architect of the two-sciences settlement. Vico’s vision of ontological hybridity, I argue, offers more robust support to the Perestroikan goals of methodological pluralism and political engagement than the two-worlds ontology Perestroikans often invoked.