132 THE AIM AND ACHIEVEMENTS OF SCIENTIFIC METHOD. 



contexts of experience which are not of the same class as 

 the phenomena in question. Finally, so far from becoming 

 merged in the Objective facts which they render intelligible, 

 we have seen that their fate is to disappear altogether when 

 they have enabled us to arrive at a " complete synoptic 

 inventory " of these facts. 



In support of this view many arguments may be brought. 

 The one most relevant (from the standpoint here adopted) is that 

 the concept of the "realities" which are to replace the sensible 

 data are themselves abstracted from those data. Thus Duhem* 

 not only argues, in a spirit entirely consonant with the spirit 

 of this essay, that water is not really the hydrogen and oxygen 

 which disappear when it is formed, but also shows that the 

 atomic hypothesis upon which it is possible to conceive the 

 " elements " as still present in the " compounds " is derived 

 historically from Newton's famous Query 31.f In this passage 

 Newton suggests the application of the ideas that he had gained 

 from his study of planetary bodies to the analysis of the 

 behaviour of the bodies manipulated in experiments. Similar 

 observations occur in several of Mr. Merz' splendid chapters, 

 and have been repeatedly illustrated in the course of our 

 discussions in Chapters III and IV. More recently still it 

 has been pointed outj that the most thorough-going quasi- 

 metaphysical attempt to account for perceived physical events 

 is vitiated by the same circle. The most striking feature of the 

 electric theory of matter is that it exhibits the property of 

 " mass " as the consequence of the motion of " electrons." But 

 to reach this result properties of the electromagnetic field are 

 appealed to, and these properties are defined by differential 

 equations into which the notion of mass derived from the study 

 of molar bodies itself enters. 



* In his Le Mixte et la Combinaison chimique, 1902, and in other 

 writings. See also supra, p. 82. 



t Supra, p. 78. 



J See a review of works on " Electrontheorie," Jiy H. A. Wilson, in 

 Nature for June 22, 1905. 



