THE CONCEPT OF EVOLUTION 357 



Secondly, the capacity of organic variation which is 

 distinctive of living creatures, is only adumbrated among 

 non-living things. A living unity, whether a full-gro\vn or- 

 ganism or an implicit organism (the germ-cell), gives rise 

 to something new. A genius is born, a mutation occurs; 

 this is something apart from the ubiquitous flux of weather- 

 ing, rusting, and the like in the inorganic world. The latter 

 corresponds to the wear and tear of organisms, the disintegra- 

 tion and ageing, the incorporation of the substance of one 

 creature into that of another. It is one thing to say with 

 the Greek philosopher " all things flow '' ; it is another to 

 recognise creative evolution. For an approach to organic 

 variation we must look to such phenomena as the change of 

 one crystalline form into another, or the elaboration of a 

 carbon compound in certain surroundings, or, nearest 

 of all, perhaps, the change of Uranium into Radium and 

 Helium. 



But, third, when an inorganic material system — whether 

 a cloud or a mineral — changes from one form or phase to 

 another, it has its analogue rather in organic development 

 than in organic evolution. For organic evolution implies a 

 succession of generations, a staking of individual lives and 

 losing them, a sacrifice of variants and of types and even 

 of races, a sifting so that many who run the race and fight 

 the fight with success fail eventually to inherit the promises. 

 Even if the chemical evolutionist gives us a genealogical 

 tree of Radium-lead, through Radium to Uranium (with 

 successive losses of Helium), we have only an analogy to 

 organic pedigree. 



It is indeed tempting to compare the conflict of forces in 

 the inorganic domain and the resulting equilibrium with the 

 struggle for existence among organisms and the resulting 



