36 THE AIM AND ACHIEVEMENTS OF SCIENTIFIC METHOD. 



unnecessary rather than that it is demonstrably false. First 

 will come the psychologists who point to the manner in which 

 our concept of Space as " a single continuous receptacle " arises 

 from our perceptual experiences as indicative of its purely 

 psychological value as a great "economical invention/' An 

 interesting argument of this type is that developed by Professor 

 Poincare, who holds that our three-dimensional space is really 

 nothing more than a conventional reduction now hereditary 

 in the race of the indefinitely numerous "dimensions" of 

 an extensive character which our muscular sensations must 

 originally give us.* 



Finally come the arguments based on the "descriptive" 

 view of Science. Thus to M. Poincare, faced with the old 

 question whether the earth revolves or whether the firmament 

 undergoes a diurnal revolution about it, the two propositions 

 " ' la terre tourne/ et ' il est plus commode de supposer que la 

 terre tourne/ ont un seul et meme sens ; il n'y a rien de plus 

 dans Tune que dans I'autre/'f 



When faced with the fact that results of scientific research 

 such as Newton's law of mutual accelerations, the law of 

 "centrifugal force," and certain results of modern electrical 

 theory seem to be meaningless in the absence of absolute 

 space, these epistemologists reply that such theoretical results 

 are simply means by which we can analyse and describe the 

 actual behaviour of the universe as it is given to us : and that 

 we have no warrant for applying these descriptive instruments 

 to hypothetical cases in which alone they could be thought of 

 as proving the existence of an absolute space. Thus (they 

 argue, in effect) although you may apply with success to the 

 behaviour of the water in a rotating bucket the descriptive rules 

 which you reached by analysis of the behaviour of the moon, yet 

 your success is dependent upon the fact that you worked in the 



* Science et Hypothese, p. 73. 

 t Op. cit., p. 141. 



