AND ITS SELF-CONSERVATION. 43 



find ourselves involved in contradiction. From this con- 

 tradiction we are to seek a way of escape. 



In doing so, let us assume any series of particles, as : 



(1) (2) (3) (4) (5) 



If repulsion is an essential characteristic of matter, 

 then each of these particles must repel every other in the 

 series. Hence (3) repels (2) and (1) on one side, and (4) 

 and (5) on the other side. But each of these repels (3) 

 in turn. That is, repulsion is a relation of reciprocal 

 action. One particle cannot repel the other without 

 being in turn repelled by it. Indeed, there can be no 

 exertion of force in any direction except in so far as there 

 is opposition or resistance from that direction. There 

 can be no push without something to push against no 

 action without a corresponding reaction. And the degree 

 of force actually exerted in either direction will depend 

 upon the degree of force actually exerted in the opposite 

 direction. So that, no matter what possibility of force 

 there may be in (3), it can actually repel (2) only in so 

 far as it is repelled by (2). And the same is true of 

 whatever pair we may consider. 



But (3) repels (2) not merely by its own isolated 

 power of repulsion (setting aside for the moment the ques- 

 tion of the possibility of such isolated power), but also 

 with the added impetus which it receives from the repulsion 

 exerted upon it by (4) and (5). It is evident, then, that 

 not only do (1) and (2) mutually repel each other, but also 

 that (2) is actually driven toward (1) by the cumulative 

 repulsions between itself and (3), (4) and (5). 



It is true that while (4) and (5) repel (2) through 

 (3), they also repel (1) through both (3) and (2); so 



