Herman Paul is Professor of the History of the Humanities at Leiden University, The Netherlands. Adriaan van Veldhuizen is Assistant Professor in Historical Theory at Leiden University, where he coordinates the PhD program in history and plays a leading role in the research project, "The Demands of our Time: Epochal Thinking from 1800 to the Present." He published a Dutch-language book on the history of socialism and several articles on historical theory, most recently in History and Theory.