MATTER 257 



after a combination is seen from a perceptual example not 

 to involve of necessity a sameness of substratum. 



Now I have cited this example of the wave for two 

 reasons. In the first place, it shows us that it is possible 

 to conceive atoms as penetrable by atoms, and as varying 

 from moment to moment in their substratum, without at 

 the same time denying the possibility of their physical 

 permanency and individual reproduction after chemical 

 combination. To consider an atom as consisting always 

 of the same substratum, and as impenetrable by other 

 atoms, may help us to describe easily certain physical and 

 chemical phenomena ; but it is quite conceivable that 

 other hypotheses may equally well account for these 

 phenomena, and this being so we have clearly no right 

 first to project special conceptions into the world of real 

 phenomena, and then to assert on the strength of this that 

 matter, penetrable in itself, is impenetrable in its ultimate 

 element, the atom. Clearly impenetrability is neither in 

 perception nor conception a necessary factor of material 

 groups of sense-impressions. Further, the permanence 

 and sameness of such a group do not necessarily involve 

 the conception of a permanent and the same substratum 

 for the group. 



My second reason for citing this wave example lies in 

 the light it throws on the possibilities involved in the 

 statement : " Matter is that zvJiich moves' The wave 

 consists of a particular form of motion in the substratum 

 which for the time constitutes the wave. This form of 

 motion itself moves along the surface of the water. 

 Hence we see that besides the substratum something else 

 can be conceived as moving, namely, forms of motion. 

 What if, after all, matter as the moving thing could be 

 best expressed in conception by a form of motion moving, 

 and this whether the substratum remain the same or not ? 

 To this suggestion we shall return later, as it is one 

 extremely fruitful in its results. 



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