132 TIME 



that all electric phenomena be considered as taking place, not 

 in separate time and space, as had been thought so far, but in 

 a space and time welded together so intimately that, following 

 Sir James Jeans' expression, it is impossible to separate space 

 from time in any absolute manner. None of the phenomena 

 of nature is capable of dissociating the result into a separate 

 space and time. 



There is nothing in this statement to astonish the reader if 

 he has followed the preceding paragraphs. On the contrary, 

 a different conclusion would surprise him if he has thoroughly 

 grasped Bergson's and Pearson's notion of duration in which 

 consciousness necessarily intervenes, and also the simple 

 elementary fact that nothing can exist instantaneously, seeing 

 that the verb 'to exist' in itself implies the notion of time. 

 If the reader is thoroughly impregnated by these purely 

 logical ideas, he will not be able to conceive how it is possible 

 to think otherwise. As a result, the notion of time as a fourth 

 dimension not of space, as has often erroneously been said, 

 but of the universe, imposes itself as being not only plausible 

 but necessary.^ 



I must say that I cannot see any difficulty in conceiving 

 what Minkowski calls 'the four-dimensional continuum'. The 

 perusal of works such as those of Eddington, Jeans, and 

 Bergson's Duree et Simultaneite, give the impression that it 

 requires a kind of intellectual feat. 



'It is difficult to imagine a new dimension if one starts 

 from three-dimensional space,' writes Bergson, 'seeing that 

 experience does not show us a fourth one. . . .' 



'It is difficult enough to imagine the four-dimensional 

 continuum. . . .' writes Sir James Jeans. 



I wonder if this is not another snare set for us by 'words'. 



In other terms is it not principally the word 'dimension' 



which makes things difficult? For if we persist in trying to 



imagine a supernumerary dimension of space we cannot help 



considering it as being of the same order, of the same nature 



^ In the Encyclopedia of 1754, d'Alembert had foreseen this con- 

 ception, or more exactly had mentioned '<3 clever man of his acquaiti- 

 tatice who believes that time could be considered as a fourth dimension' . 



