„Another way of emphasizing this diversity is to argue that if one cannot forecast (predict), one does not have a theory, and that forecasting is the weakest link in the chain of the management sciences at present. Indeed, if one cannot predict one cannot measure, and if one cannot measure, then there is no "theory."
This argument will seem entirely too strong to some. We do "forecast" in terms of probability distributions, and we do make measurements in terms of "costs." Of course, the management scientist has done all sorts of things with the concept of cost which few cost accountants would condone. But in the laboratory and outside it in industrial studies, one sees the emergence of a cost concept which eventually should revolutionize the measurements in managerial policy-making.
Theory and fact are just two sides of the same coin, but the two sides of a coin are different, and this difference will continue to characterize the development of management science.“
— C. West Churchman American philosopher and systems scientist 1913 - 2004
1940s - 1950s, "Management Science — Fact or Theory?" 1956, quote in: Fremont A. Shull (ed.), Selected readings in management https://archive.org/stream/selectedreadings00shul#page/n13/mode/2up, , 1957. p. 8