(p. 144.) In all Western countries, the inventory of physical facilities for economic production changes. The inventory at any given moment is unquestionably important, but it is like a single frame of a movie; taken alone, it misses all the action, and it is the action that we need to understand and that holds the promise of economic advance to non-Western countries.
Source:
Rosenberg, Nathan, and L.E. Birdzell, Jr. How the West Grew Rich: The Economic Transformation of the Industrial World. New York: Basic Books, 1986.