168 A THEORY OF LIFE 



a clock-weight when the clock is not going, and 

 so on. 



We need not develop this matter further ; 

 but one point must be alluded to, namely, the 

 gradual exhaustion of the available energy in the 

 changes from one manifestation to another. In 

 all physical processes heat is evolved, which heat 

 is distributed by conduction and radiation and 

 tends to become universally diffused throughout 

 space. When complete uniformity has been 

 attained, all physical phenomena will come to an 

 end ; in other words, our solar system must come 

 to an end, and it must have had a beginning. It 

 is a well-known argument. Is there anything to 

 rewind the clock which is running down before 

 our very eyes ? It was once urged that stellar 

 collisions, and such-like things, might permit us 

 to postulate a cyclical arrangement (and thus 

 rearrangement) of universal phenomena ; but 

 that hypothesis does not seem to find any sup- 

 porters to-day. 



In his interesting book, already mentioned, 

 Dr. Johnstone called attention to the power 

 possessed by living matter of reversing the 

 process ; but no reversal of this kind and extent 

 can make up for the constant degradation of 

 energy which is taking place all round us. We 

 mention this because it shows that " energy " 

 cannot, in any case, afford an eternal solution, 

 but only a temporal and therefore a limited one. 

 No one doubts that there is energy in the living 

 thing, nor that there are what the author calls 

 " complexes of energies." No one, again, will 



