When you can measure what you are speaking about and express it in numbers, you know something about it, but when you cannot express it in numbers, your knowledge is of a meager, unsatisfactory kind.
Shaw, R. H. and Elford, C. R.
"How You and I Record the Weather,"
Iowa Farm Science: Vol. 12
, Article 5.
Available at: https://lib.dr.iastate.edu/farmscience/vol12/iss11/5