ABSTRACT
In the late 19th century the eminent scientist William Thomson, Lord Kelvin (1824–1907), remarked:
I often say that when you can measure what you are speaking about, and express it in numbers, you know something about it; but when you cannot measure it, when you cannot express it in numbers, your knowledge is of a meagre and unsatisfactory kind: it may be the beginning of knowledge, but you have scarcely, in your thoughts, advanced to the stage of science whatever the matter might be. (William Thomson, Lord Kelvin, 1891, p. 80)
