30 BIOLOGICAL ASPECTS OF HUMAN PROBLEMS 



tions from time to time. In the cell republic the 

 greater number of the living elements or cells main- 

 tain approximately the same position with regard 

 to each other. Relatively few types of cells are 

 ambulatory. Moreover, the cells are definitely com- 

 mitted to their occupation ; once a liver cell, always 

 a liver cell. This arrangement, so clearly in the 

 interest of efficiency, is one which the builders of 

 states might do well to ponder and perhaps to 

 imitate. There is another striking contrast. The 

 maintenance of the state is, broadly speaking, 

 dependent on the use of the reproductive powers of 

 the individuals which comprise it. The maintenance 

 of the human individual depends, indeed, on a power 

 of renewal possessed by the individual cells. But 

 many types of cells have only a feeble or question- 

 able power of reproduction. For example, neither 

 nerve cells nor muscle cells regenerate if injured, 

 except in an imperfect way. And not only must 

 the life of the individual come to an end, which 

 theoretically need never happen to a state, 

 but the reproduction of the individual is intrusted 

 to specific cells that have been set aside for the 

 purpose. 



Yet the comparison between state and living body 

 holds good in several noteworthy ways. There is, 

 first of all, a remarkable subdivision of labor. In the 

 animal body are represented parts or cells which 

 govern and coordinate, parts which prepare and 

 transform foodstuffs, parts which act as carriers 



