CH. xvn METAPHYSICS OF NATURAL SELECTION 193 



as the only force. Soup (once more) is the better of 

 a handful of salt, but you will never make salt into 

 soup. If selection gets hold of a good thing it knows 

 how to keep hold of it, or even how to push it on ; but 

 it can originate nothing. It will also be possible to hold 

 an opinion midway between these extremes. " Natural 

 selection " by itself may be a conceivable cause of dis- 

 tinct species, yet it may be thought that other causes 

 exist in nature which do the work more rapidly (Natural 

 Selection A possible ; plurality of causes comes in, and 

 Natural Selection C is the actual process). 



Analysis of Natural Selection C. The example of 

 one concrete force assumed to be working in combination 

 with natural selection may make our meaning clearer. 

 Let us take use-inheritance. Lamarckism and Darwinism 

 can be held separately, or they may be united ; but [we 

 have argued that] since Darwin has pointed to natural 

 selection no one can reasonably ignore it or utterly deny 

 it. If we are to be Lamarckians at all, we must now 

 be Darwinian Lamarckians. We may differ from Darwin 

 as to the relative value of the two forces. Probably any 

 direct evolutionary force which exists and operates must 

 count for much more in the result than the indirect 

 force of natural selection which co-operates with it. 

 Nevertheless, natural selection must be producing some 

 effect, if any process for the evolution of species is 

 going on. 



If use-inheritance is working for evolution, natural 

 selection will back it up in two ways, distinguishable 

 from each other if not objectively distinct. Cases of 

 relapse by "Atavism," below the standard already 

 reached, will be wiped out ; natural selection will be 

 a safeguard or rear -guard to the process of evolution 

 (Natural Selection B). And secondly, in proportion as 



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