92 CREATIVE EVOLUTION CHAP. 



ing, is one of the most solid positions of neo-Lamarck- 

 ism. But if this cause is nothing but the conscious 

 effort of the individual, it cannot operate in more than 

 a restricted number of cases at most in the animal 

 world, and not at all in the vegetable kingdom. 

 Even in animals, it will act only on points which are 

 under the direct or indirect control of the will. And 

 even where it does act, it is not clear how it could 

 compass a change so profound as an increase of com 

 plexity : at most this would be conceivable if the 

 acquired characters were regularly transmitted so as 

 to be added together ; but this transmission seems to 

 be the exception rather than the rule. A hereditary 

 change in a definite direction, which continues to 

 accumulate and add to itself so as to build up a 

 more and more complex machine, must certainly be 

 related to some sort of effort, but to an effort of far 

 greater depth than the individual effort, far more 

 independent of circumstances, an effort common to 

 most representatives of the same species, inherent in 

 the germs they bear rather than in their substance 

 alone, an effort thereby assured of being passed on to 

 their descendants. 



So we come back, by a somewhat roundabout way, 

 to the idea we started from, that of an original impetus 

 of life, passing from one generation of germs to the 

 following generation of germs through the developed 

 organisms which bridge the interval between the genera 

 tions. This impetus, sustained right along the lines 

 of evolution among which it gets divided, is the 

 fundamental cause of variations, at least of those that 

 are regularly passed on, that accumulate and create 

 new species. In general, when species have begun to 



