58 THE WORLD-ENERGY 



Even the infinitesimal has its value, however, and so 

 we proceed upon the line of our argument, not without 

 some glimmer of hope. 



The course of the argument thus far has tended toward 

 the conclusion that the essence or truth of matter is force 

 or energy. And we have seen that such eminent physicists 

 as Thomson andTait define matter to be "that which can 

 be acted upon by, or can exert, force/' We have also seen 

 that Professor Tait accepts as a tentative definition of 

 matter, "whatever can occupy space." 



In either case matter cannot be a something apart from 

 force, but, rather, must be identical with force, so far as 

 we can ever know anything about it. For, as already 

 noticed, it is only through a counter force opposing the 

 force we ourselves exert that we can know anything about 

 " whatever occupies space," or about space either, seeing 

 that we become aware of extension only through the 

 extended. 



But that which is extended, or "can occupy space," is 

 in that very fact divisible, at least theoretically, without 

 limit ; and it is divisible, experimentally, far beyond our 

 powers of observation. Whence all bodies within our ex- 

 perience must be aggregations of infinitesimal bodies 

 beyond our experience at least beyond our sensuous 

 experience. Nor is there any necessary contradiction 

 between the " metaphysical " conception of the infinite 

 divisibility of matter, and its practically limited division, 

 as will perhaps become more evident with the further 

 progress of the argument. 



The Democritean conception of the atom, or ultimate 

 division of matter, has, of course, long been given up. 

 Instead of the minute, absolutely hard, and therefore 



