Abstract
Working from a unique background in both archaeology and philosophy, R.G. Collingwood undertook to revise historiography by redefining the concept of evidence. Historians through the modern period, in their willingness to emulate the natural sciences, had absorbed a brand of empiricism which was not only compromising historical thinking but also frustrating the service which history, ideally, should provide for enlightening human experience. What comes of his project is a concept of evidence which may be described as a priori.