THE LAW OF EVOLUTION CONCLUDED. 393 



ponent matter, there necessarily arise secondary re-distri- 

 butions of its retained motion. As fast as the parts are 

 transformed, there goes on a transformation of the sensi- 

 ble or insensible motion possessed by the parts. The parts 

 cannot become progressively integrated, either individually 

 or as a combination, without their motions, individual or 

 combined, becoming more integrated. There cannot arise 

 among the parts heterogeneities of size, of form, of qual- 

 ity, without there also arising heterogeneities in the amounts 

 and directions of their motions, or the motions of their 

 molecules. And increasing definiteness of the parts implies 

 increasing definiteness of their motions. In short, the 

 rhythmical actions going on in each aggregate, must dif- 

 ferentiate and integrate at the same time that the structure 

 does so. 



The general theory of this re-distribution of the retained 

 motion, must here be briefly stated. Properly to supple- 

 ment our conception of Evolution under its material aspect 

 by a conception of Evolution under its dynamical aspect, we 

 have to recognize the source of the integrated motions that 

 arise and to see how their increased multiformity and defi- 

 niteness are necessitated. If Evolution is a passage 

 of matter from a diffused to an aggregated state — if while 

 the dispersed units are losing part of the insensible motion 

 which kept them dispersed, there arise among coherent 

 masses of them, any sensible motions with respect to one 

 another; then this sensible motion must previously have 

 existed in the form of insensible motion among the units.. 

 If concrete matter arises by the aggregation of diffused 

 matter, then concrete motion arises by the aggregation of 

 diffused motion. That which comes into existence as the 

 movement of masses, implies the cessation of an equivalent 

 molecular movement. While we must leave in the shape of 

 hypothesis the belief that the celestial motions have thus 

 originated, we may see, as a matter of fact, that this is the 

 genesis of all sensible motions on the Earth's surface. As 



27 



