Addresses historical skepticism by presenting histories as testable theories of the past. Setting aside barren issues such as the scientific status of history, Murray G. Murphey develops an empirical approach to historical study that can yield theories (interpretations) that are testable and confirmable. He examines the evidence on which historical theories are based, the types of explanations used, and particularly the way historical theories are tested. The book treats not only the actual process of historical research but also the philosophical problems involved in historical work. The treatment of causation is new, as is the discussion of epistemology. In his discussions, Murphey covers a wide range of sources and examples, including Frederick Jackson Turner, the Gospels, perspectives on the causes of the Great Depression, the Vinland Map, witchcraft, and material culture. The book is addressed to all who do history or write about it, and it will be a useful text for those who teach courses in historiography.