SELECTION 473 



has been shown by Johannsen, do Vries, Jennings, Pearl, and others 

 that selection does not count for much within pure-lines or inbred 

 stocks. Tlie abundant * fluctuations ' that occur there cannot be used 

 as a basis for selection, for they are not transmissible, and are 

 probably for the most part of the nature of modifications. 



As our whole view of Animate Nature is coloured by our estimate 

 of the validity and importance of the Selection-Theory, it is useful 

 to consider some of the more serious criticisms, e.g., that slight 

 initial changes could not have survival value, that they would bo 

 swamped or levelled down by inter-crossing. ... It does not seem 

 too much to say that the theory survives these criticisms and has 

 been the better for them. 



It is very important to recognise that Natural Selection is a 

 technical expression for a manifold, almost ubiquitous, and often 

 subtle process of sifting, which has, in most cases, a particular ref- 

 erence to particular conditions in time and space. It does not work 

 consistently towards an ideal of fitness, but it eliminates inconsistent 

 non-viable constitutions; it often operates in reference to an intricate 

 web of life, and thus a nuance — a shibboleth — may have survival 

 value; it operates, generally speaking, in relation to a Systema 

 Natura3 which has been increasingly elaborated through the ages, in 

 which even ideas and affection get embodied, and this is part of 

 the explanation of the progressiveness of evolution. Another part 

 of the explanation of the progressiveness, which has always been a 

 puzzle except to teleological interpretation, is what may be called 

 organismal momentum. Organisms run on a compound interest 

 principle. 



The question rises again whether the operative factors in organic 

 evolution are more than complications or compositions of factors 

 which operate in inorganic genesis. The answer is, much more. 

 Natural Selection operates on what is not accounted for mechan- 

 ically, and the sifting process itself is more than mechanical. What 

 Ward has shown in regard to Subjective Selection is vitally impor- 

 tant to an accurate view of the facts. The same conclusion may be 

 reached from a different set of data, the phenomena of preferential 

 mating. 



In variation and selection we have, so far as we know, the chief 

 tactics of Animate Evolution. A move is made and it is tested; 

 a new idea occurs and it is criticised. But a formal statement of 

 the tactics is fallacious. It conceals the heart of the matter, that 

 living creatures with a will to live, with an insurgent self-assertive- 



