Giuseppe Longo is Research Director at the Centre nationale de la recherche scientifique (Emeritus) at the Cavaillès interdisciplinary center of Ecole Normale Supérieure, Paris (ENS). He was previously Research Director in mathematics, then in computer science, at ENS (1990–2012), and a professor of mathematical logic and computer science at the University of Pisa (1973–90). Longo spent three years in the US, including at the University of California, Berkeley, Massachusetts Institute of Technology, and Carnegie Mellon University, as a researcher and visiting professor, and also spent several months at the University of Oxford and Utrecht University. He has authored and co-authored more than 100 papers and three books. He recently extended his research interests to include the epistemology of mathematics and theoretical biology.