This article traces the main methodological and substantial similarities between Reinhart Koselleck's notion of Begriffsgeschichte and J. G. A. Pocock's approach to the history of political thought. Both approaches are responses to the shift in the unit of analysis in the study of human historical consciousness. Rather than focusing on ideas, Koselleck and Pocock concentrate on how language articulated heightened awareness of historical change. Concepts and paradigms reflect in varying manners the intensity of historical sedimentation. The more sedimentation, less space there is for innovation, and political action tends to be conservative. Conversely, unstable concepts or obsolete paradigms, reflect historical change and space for linguistic innovation.