74 INTRODUCTION TO PHILOSOPHY OF SCIENCE 



among symbols, dispensing with pictorial images and such 

 adventitious aids" * one does not truly understand the real 

 phenomena. On the other hand there is a large group of 

 scientists, among whom are Hobson, Mach, Ostwald, and 

 Poincare, who believe that images and models are apt to be 

 misleading and should be replaced by abstract conceptual 

 schemes and word-representations. Probably there would 

 also be found in the latter group all of those who argue that 

 physical events are simply measurable entities which can 

 be symbolized only by numbers and functional relations 

 between variables. The conflict may therefore be formulated 

 in terms of the relative adequacy of concrete as over against 

 abstract symbolism. 



Unfortunately the problem is none too precise when 

 described in this way, for the dichotomy concrete-abstract is 

 itself ambiguous. It may refer to any one of a large number 

 of distinctions, all of which are considered as reducible to the 

 distinction between the perceivable and the unperceivable. 

 This is not a very helpful analysis for there are probably 

 many reasons why any event may or may not be readily 

 perceived. Events which are remote in space and time can- 

 not be readily perceived, nor can events which are very large 

 or very small, or very long or very brief. Events which are 

 highly complex, i.e., which exhibit many aspects, cannot 

 enter clearly into perception, nor can events which are 

 highly simple, i.e., the aspects of complex events considered 

 in isolation from one another. Thus one could construct such 

 a list of unobservable events as the following: Mars, the birth 

 of Caesar, the solar system, genes, life upon the earth, a 

 flash of lightning, a human organism, and length without 

 breadth or thickness — but in each case the elusive character 

 of the event would be due to a different factor. A thorough 

 examination of the problem at hand would require a detailed 

 consideration of these various dimensions of obscurity. 



For present purposes, however, the problem of the relative 

 adequacy of icons and characterizing symbols may be left 



1 Ibid., p. 13. 



