Quantitative Imperative Versus the Imperative of Presuppositions

The quantitative imperative is the view that studying something scientifically means measuring it. W. Thomson (Baron Kelvin of Largs), a leading nineteenth-century British physicist, expressed this in succinct terms:

When you can measure what you are speaking about and express it in numbers, you know something about it, and 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 thought advanced to the stage of a science. (Thomson, 1891, pp. 80–81)