THEORIES OF IMMUNITY 191 



An albuminous micelle, considered as a unit of specific 

 function can no more assimilate entire " micelles," whether 

 homogeneous or specifically different than a house or a 

 machine could be constructed from other complete houses 

 or machines. 



In either case, the first step must be to demolish, isolate 

 and separate the individual materials, which will then possess 

 no specificity and with which new units can be reconstructed 

 according to the plans and specifications. 



The differentiated superior organism is guided in its choice 

 of food by its organs of sensation and by its intelligence; 

 the second and third degree units are guided by positive 

 or negative chemotaxis which is but the non-differentiated 

 combination of feeling and intelligence; and it is likewise 

 affinities or chemotaxis which determine the formation of 

 antibodies as well as the action of these latter on their 

 antigens. 



In order to well understand the mechanism of the results 

 which these reactions may have for the entire organism, we 

 must always remember that: 



1. The work of demolition or of digestion for each nutritive 

 unit must take place outside of its interior. The particle, 

 the cell, and the entire organism, expel from their interior 

 beyond their protecting membranes, the substances (anti- 

 bodies) or, more generally speaking the energy which is 

 needed for the digestion or transformation of foreign sub- 

 stances (antigens). This is done by that chemotaxis which 

 by sensation, intelligence and memory can act at a distance. 

 Thus it is that the sight of food causes the sensation of appe- 

 tite and the secretion of gastric juice, and that the sight or 

 odor of individuals of opposite sex causes amorous feelings 

 and corresponding reactions of the reproductive organs. 



2. In differentiated organisms each functional unit, while 

 its reactions obey its own chemotaxis, must also conform 

 to the chemotaxis of the whole. The "micelle" is influenced 

 by the chemotaxis of the whole cell, the cell by the chemo- 

 taxis of the organism, the organism by the surroundings and 

 the society in which it lives, and so on; and the history of 

 the greatest organization of units, the society of nations is 



