1. Ian Hacking, a Fellow of the American Academy since 1991, holds the chair of Philosophy and History of Scientific Concepts at the Collège de France. His work spans the philosophy of science, the philosophy of language, the theory of probability and statistical inference, and the socio-historical examination of the rise and fall of disciplines and theories. His most recent books are “Mad Travellers” (1998), “The Social Construction of What” (1999), and “Historical Ontology” (2004).