n] BIOLOGICAL FOUNDATIONS 51 



system of diverse parts, yet this mere fact of existence 

 as a single and separate material body is a first step 

 towards Bergson's " closed system." In non-conscious 

 animals, indeed, where individuality is bound down 

 within the limits of physical substance, this separate- 

 ness in space is the only foundation upon which such 

 a closed system could be built. Besides this, it 

 presents itself as a whole unit to the forces of the 

 outer world: living substance thus starts with its 

 foot upon the ladder leading to independence, for 

 its molecules cohere, and all know that union is 

 strength. 



Given the complex molecules of fixed composition, 

 and, if of various kinds, existing in a fixed proportion, 

 there will be definiteness of shape and action ; and 

 given assimilation the reproduction of new molecules 

 identical with the old there is the possibility of 

 continuance for this shape and this action. 



Analysed thus far, our organism has revealed itself 

 as very similar to a crystal in its definite boundaries, 

 definite and permanent form, and, we may add, in its 

 capacity for growth. It differs only in having a mode 

 of working as well as a form which is continuous. 



The organism, however, has two further properties 

 which make it at once more definite and more in- 

 dependent than the crystal. It is more independent, 

 more self-determining, because it can build up its 

 complicated molecules out of simple substances, and 



42 



