366 INTRODUCTION TO PHILOSOPHY OF SCIENCE 



merits are scientific laws, and their character may be exam- 

 ined immediately. 



law: scientific content 



Law, at the scientific level, is simply a refinement of 

 empirical law. A scientific law also states a repeated associa- 

 tion of events. But greater attention is paid to precision and 

 accuracy of formulation. This feature of scientific law may be 

 discussed from the point of view of the three aspects con- 

 sidered in the previous section: (1) the kinds of events 

 correlated, (2) the nature of the correlation, and (3) the 

 meaning of "repeated." 



(1) The important problem in this connection is asso- 

 ciated with the question of measurement. Is there such a 

 thing as a qualitative law, or must a scientific law be quanti- 

 tative? Many would insist that qualitative laws are not 

 laws at all. Yet this seems hardly fair to the non-physical 

 sciences. The biological and the humanistic sciences are 

 not in a position to use techniques of measurement as suc- 

 cessfully as are the physical sciences, since the character of 

 the subject matter does not always permit it. Presumably 

 all that can be required of them is the introduction of 

 methods of measurement where the content of the science 

 permits, and the use of other techniques of precision — such 

 as accurate definition and ascertainment of frequencies — 

 where the subject matter does not permit measurement. 

 Qualitative correlations occur even in physics, and the 

 question as to whether these are properly to be called physi- 

 cal laws is debatable. "Shall we classify in the list of physi- 

 cal laws such purely qualitative observations as the proposi- 

 tions: copper conducts electricity, the melting point of ice 

 is lowered by pressure, a grating forms a spectrum, etc., or 

 such numerical statements as that there are three states of 

 matter, there are two types of waves possible in an elastic 

 medium — compressional and distortional, etc.? It is con- 

 ceivable that a difference of opinion may be honestly enter- 

 tained here. Some authors take the view that these really 



