For several centuries, historians have tried to answer the question: "Why is Western Europe (and later, North America) the dominant world power?" Past explanations cited culture, or "great men" who influenced the course of history. Stanford historian Prof. Ian Morris casts doubt on those explanations, instead taking a data-driven approach to the question that attempts to measure "social development" over history and find explanations for it. In this episode of Rationally Speaking, Julia delves into Morris' method and conclusions, and asks: can we make causal inferences about history?

Ian Morris is Willard Professor of Classics and Fellow of the Archaeology Center, Stanford University. He is a historian and archaeologist. He has excavated in Britain, Greece, and Italy, most recently as director of Stanford's dig at Monte Polizzo, a native Sicilian site from the age of Greek colonization. He is also the author of a number of books, among them: "Why the West Rules--for Now". "War! What Is It Good For?", and "Foragers, Farmers, and Fossil Fuels."