THEORY OF THE DEVELOPMENT OF ORGANISMS 137 



a complexity that has arisen by the interaction of 

 the same characters of many men in co-operation. 



Similarly the activity of the egg in growth 

 and cell-formation is an inexhaustible source of 

 new complexity ; for the self-multiplying systems 

 of units, always binding themselves into higher 

 complexes, continually enter into new interrelations, 

 and afford the opportunity for new combinations of 

 forces in fact, of new characters. 



Both cases the course of the development of 

 the egg- cell into a man, and of men into a state 

 depend upon epigenesis, not upon evolution. 



The comparison may be carried into details. 



The more complex and higher organisation of 

 human society occurs in this fashion : of the 

 numerous single individuals, all of which are 

 endowed with the various incipient human char- 

 acters, some individuals elaborate some incipient 

 characters, others other characters, and these come 

 to play correspondingly different parts. The special 

 differentiation undergone by any individual depends 

 upon the special place he comes to occupy in the 

 whole of which he is a part, not upon really 

 different organisation residing in him from his 

 birth. Beside those characters which have de- 

 veloped specially in his case, there lie dormant the 

 rudiments of all the characters possessed by men, 

 and, under different conditions, these might have 

 come to development. 



Differentiation in multicellular organisms takes 

 a similar course. Every cell, by doubling division 

 of the egg, receives all the rudiments of its kind ; 



