MATTER, MOTION, AND FORCE 



along this line is to assert that force may be 

 expended without effect. Still more obvious 

 does this become, when we remember that 

 " our only evidence of excess of force is the 

 movement it produces." Since we know force 

 not in itself, but only as revealed to conscious- 

 ness in matter and motion, it follows that mo- 

 tion in any direction is the only proof we have 

 that there is a surplus of unantagonized force 

 acting in that direction. So that our theorem 

 becomes almost an identical proposition. But if 

 we ask why the greater of two opposing forces 

 is that which causes motion in its own direction, 

 there can be no answer save the one already 

 given. There is no warrant save the conscious- 

 ness that the unneutralized surplus of force can- 

 not cease to act. 



The simplest case contemplated by this cor- 

 ollary is that of a moving body left to itself. 

 There being here no force involved, save the 

 body's own momentum, the direction of motion 

 is an infinite straight line. But since the reali- 

 zation of such a case would involve the annihi- 

 lation of all matter save the body in question, 

 it is obvious that no such simple case can ever 

 have existed within the limits of the knowable 

 universe. The simplest case of motion which 

 can come within our cognizance is really com- 

 plex to a degree which baffles computation. 

 Mr. Spencer somewhere remarks that when a 

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