THE GENESIS OF LIVING ORGANISMS 235 



germ-cell, which are called genes. The newly discovered 

 natural force works rhythmically according to a definite 

 plan ; therefore it must be called a rule. The agency through 

 which it materialised itself we called the impulse, and we 

 identified it with the impulse that precedes our own voluntary 

 actions. 



As soon as the framework is completed and the function 

 sets in as a purely material process, the control over the 

 impulses passes from the rule of genesis to that of function ; 

 this comes to the rescue when there is any injury, and, also 

 with the help of the genes, carries out the repairs ; in addition, 

 it controls the growth of the formed but not yet full-grown 

 animal. 



We learn from these facts that, in addition to the rule 

 that we form with the aid of our apperception when we con- 

 sider the working of some particular framework (be it a living 

 being or a machine), there is also a natural factor that 

 works after the manner of a rule ; this is not operative in 

 implements, but only in organisms. 



To describe two different things as " rule of function " 

 may easily lead to confusion ; so we might speak of a function- 

 rule kept in permanence by a function-regulator. 



If we choose to use this term, then the subject is distin- 

 guished from an implement by possessing an autonomous 

 function-regulator, and it also has an autonomous rule of 

 genesis ; this, being likewise a natural factor, may be called 

 genesis-regulator. Thus the subject, as the visible mani- 

 festation of the union of both these regulators, forms the 

 most important natural factor in biology. 



