Without doubt, good numbers that characterize sharply and completely the phenomena being studied, and precise explanation of these phenomena that can be expressed mathematically, are tremendous advantages for a field of science. But not all fields of science are lucky enough to be able to achieve these features. And when they are not, nonetheless to force the phenomena studied to be characterized largely with numbers and the causal mechanisms to be described mathematically can court seriously limiting and distorting the field (...) of study. Research by economists on long-run economic development is an example of a field of research where this has happened. But unfortunately the phenomena are widespread throughout science. (shrink)