8o HOLISM AND EVOLUTION chap. 



is utterly unlike that of physical forces, which are alike, 

 which are repetitions of each other, and which can be added 

 or subtracted or otherwise expressed arithmetically. The cells 

 are different, they are differentiated in definite directions, 

 and the totality of differentiations fits into a plan or scheme, 

 the fulfilment of which constitutes the complete organism. 

 There are no repetitions, there is uniqueness everywhere, 

 and the various unique entities and their functions fit into 

 each other more or less so as to produce an organic whole, 

 unlike any other organism. And in some indefinable way this 

 whole is not an artificial result of its part; it is itself an action 

 factor like its parts, and it appears to be in definite relation 

 with them, influenced by them and again influencing them, 

 and through this continuous interaction of parts and whole 

 maintaining the moving equilibrium which is the organism. 

 Look, for instance, at the way in which organisms behave 

 when some cells or organs, necessary for their maintenance, 

 are removed or injured. It is well known that many plants 

 and animals have the power of restitution in case of damage 

 or mutilation. The newt forms a new leg in the place of the 

 severed limb. The plant supplies the place of the severed 

 branch with another. The regeneration may be effected 

 from different organs and by different organs. Thus if the 

 crystalline lens is removed from the eye of a Triton, the iris 

 will regenerate a new lens, although the lens and the iris 

 in this case have been evolved from quite different parts. 

 Numerous similar curious facts of restoration could be 

 mentioned. The broken whole in organic nature restores 

 itself or is restored by the undamaged parts. The cells of 

 the remaining parts set themselves the novel task of restoring 

 the missing parts. The power to do this varies with various 

 plants or animals, and varies also with the different parts in 

 the same plant or animal. Generally one may say that the 

 more highly differentiated and specialised an organism or a 

 cell is, the smaller is its plasticity, or the power of the remain- 

 ing cells to restore the whole in case of injury or mutilation. 

 But the fact that the power exists in numerous cases is a 

 proof that not only can the cells through reproduction build 

 up the original organism according to its specific type, but 



