Force, Energy, and Will 233 



of particular forces — heat, light, and electricity, etc. — which, 

 as such, are also abstractions; that we ought, in fact, to 

 avoid the common phrases employed in everyday life. To 

 this it may be rejoined, in the first place, that the active 

 powers of bodies do really exist, and that therefore it is most 

 reasonable to apply to similar powers a common name; 

 while for the real, though not the substantial, existence of 

 (calorific, luminous, and electric activities we have the 

 plainest evidence. Nor need we even object to the term 

 ' force ' as a common name for all active powers whatever, 

 provided its substantial existence, beside the existence of 

 the various active bodies, be not asserted or implied. But 

 secondly, I reply that though it is well to employ the 

 common terms, heat, light, electricity, etc. (meaning by such 

 terms the objective activities to which our sensibilities be- 

 come related), it is also well from time to time to make clear 

 that such entities are abstractions (though less abstract in 

 degree than ' force '), and have no existence other than ideal 

 apart from warm, luminous, or electrified bodies. 



The utility of the latter course seems to me to be made 

 plain by such considerations as the following : — It is often 

 said that bodies may, by impact, communicate motion, as 

 when one suspended ball, falling against others, ceases itself 

 to move, while another begins to be in motion. But we have 

 here no real evidence of any ' communication ' or ' transfer- 

 <'nce' of 'motion,' but only of successive and correlative 

 motions. The language used with respect to this pheno- 

 menon (the ' transference ' of ' motion ') shows the existence 

 of a tendency to regard the abstract quality 'motion as a 

 substantial entity, actually passing from one body to another. 

 But if force were a substantial entity actually passing from 

 one body to another, it would have to traverse space in so 

 passing, and what^ c^n that be which is to make it so pass, 

 and govern it in transitu ? Either for that we require 



