InOurDay, the concept of progress has fallen into disfavor in philosophical and scientific circles, although most people ordinarily seem to take it for granted, in an unanalyzed fashion. There is some reason for its rejection by the more thoughtful; in most of its expressions it was accepted in what now seems rather simplistic terms with regard to its nature and certainty. Without some idea of progress, however, an age dominated by radical change may lack any standard by which to evaluate its condition and tendencies. Furthermore, the idea of progress, and of a meaningful history, was not always presented in oversimplified terms. Pierre-Joseph Proudhon, a singular figure in the French revolutionary tradition, developed in the middle of the last century a complex and flexible thought about progress in history, and attention to his now little-known ideas may help us save the concept for political analysis and practice.