EXTENSION OF EVOLUTIONARY THEORIES 357 



A considerable number of animal characteristics have 

 been produced by a purely passive selection. Protective 

 colours, for instance, are of this kind. In this case the 

 least conspicuous animals are preserved without any 

 action on their part. 



Now that we have shown the untenability of the 

 bases of this theory, we need not go into its consequences 

 in detail. When it is said that the basic particles 

 were fully developed by their impulse to act, that the 

 action of the will in the body leaves behind it an 

 hereditary disposition, and that the animal organisation 

 is embodied volition, we can only say that these 

 statements postulate the Lamarckian principle which 

 we have rejected. 



We conclude, therefore, that the value of natural 

 selection consists in its enabling us to form a unified and 

 mechanical view of the world. In order to appreciate 

 this fully, we will now go on to consider the nature and 

 the significance of mechanism. 



