ABSTRACT
Measurement is considered to be the essence of the scientific method. The quantitative aspects of the world are looked upon as representative of its essential nature. To explain qualities is to explain them away. In general the introduction of quantitative methods permits the substitution of relations of quantitative dependence for relations of qualitative independence or of loose qualitative dependence, and of specific quantitative dependence for relations of general qualitative dependence. A high degree of systematization and integration replaces a low degree, and the aims of rationality are to that extent achieved. There are quantitative and non-quantitative qualitites, and a quality becomes a quantity when certain conditions are fulfilled. Furthermore in a logical system, such as that of the Principia Mathematica, quantitative notions are introduced late in the derivation; qualitative notions are presumed to be logically more basic, since one can derive quantitative notions from them.
