44 The Evolution Hypothesis. 



geneous becoming heterogeneous, through the integra- 

 tion of matter and dissipation of motion, and so 

 onward to dissolution. " Apparently the universally- 

 -co-existent forces of attraction and repulsion, which, as 

 we have seen, necessitate rhythm in all minor changes 

 throughout the universe, also necessitate rhythm in 

 the totality of its changes produce now an immeasur- 

 able period during which the attractive forces pre- 

 dominating, cause universal concentration, and then 

 an immeasurable period during which the repulsive 

 forces predominating, cause universal diffusion alter- 

 nate eras of Evolution and Dissolution."* There is 

 then no stability : all is everlasting flux. No mode of 

 force is fixed : forces are being constantly transformed. 

 No law is stable ; for laws are but the relations of 

 forces. Fixedness based on law is as fleeting as the 

 forces whose mode of action the law expresses. 



Among the generalizations from experience, the 

 law of gravitation may be taken as established be- 

 yond cavil ; it is accepted not only as holding good 

 throughout all actual experience, but as forming a 

 solid basis for deductions that are valid beyond the 

 reach of observation. Yet we are not thoroughly 

 imbued with the evolution doctrine if we regard it so. 

 Bodies, as we know them, tend towards one another 

 according to this law. But it is not demonstrable 

 that gravity is a property of matter universally. 



Spencer, First Principles, 183. 



