Jürgen Renn is a director at the Max Planck Institute for the History of Science in Berlin, where, together with his group, he researches structural changes in systems of knowledge. His books include, with Hanoch Gutfreund, The Formative Years of Relativity: The History and Meaning of Einstein’s Princeton Lectures and The Road to Relativity: The History and Meaning of Einstein’s The Foundation of General Relativity (both Princeton).