This article responds to Stephen Turner’s discussion of my article, "Historicism and Critique." I emphasize that radical historicism consists of substantive philosophical commitments. One commitment is to a historicized epistemology that presents objective knowledge as a product of a comparison between rival webs of belief. Another commitment is to a historical ontology that presents aggregate concepts in the social sciences as inherently pragmatic. These substantive commitments provide a plausible basis for various forms of critique. They lead to analyses of genealogical and ideological critique that differ from appeals to genealogy as a kind of groundless skepticism toward, and problematization of, all substantive commitments.