THE MECHANISM OF LIFE 567 



form and energy are inseparably connected with the changes of 

 substance, how all three in reality form a single whole, which offers 

 merely different sides for consideration. So far as scientific know- 

 ledge renders it possible, an attempt has been made to solve 

 the problem. Naturally many suppositions and many hypotheses 

 have been found necessary to close the wide gaps in our present 

 knowledge, and in spite of this many recognized gaps still remain 

 open. But cell-physiology, aided by the stern necessity of 

 its development, and its great working power, is beginning to give 

 encouragement to the highest expectations. 



III. The Constitutional Relations of the Cell-Community ^ 



So far, in all our investigations, experiments, discussions and 

 theories the individual cell, as the independent elementary organ- 

 ism, has been the chief object of interest. Now, in terminating 

 our long examination of the physiological problem, it remains to ex- 

 amine the mechanism resulting from the association of the cells in 

 a community. The life of the multicellular organism is not a 

 simple summation of the lives of the individual cells which com- 

 pose it ; many special relations are inaugurated by the association 

 of the individual cells, and these are expressed in the vital phe- 

 nomena of the multicellular organism. 



A. INDEPENDENCE AND DEPENDENCE OF THE CELLS 



It has been seen elsewhere ^ that the size of the individual cell 

 is necessarily limited. From this fact an important consequence 

 follows. A large organism can never be formed by a single cell, it 

 must be constructed from many cells. All large organisms 

 are cell-communities. By the union of the individual cell with 

 others of its like, relations are presented that influence the life of 

 the former so that its vital phenomena are different from what they 

 are when it lives free. As in the formation of every community, 

 the formation of that composed of cells requires a compromise be- 

 tween individuals. The compromise consists in the fact that every 

 cell gives up a part of its independence for the advantage that it 

 derives from association with other cells. The special form of 

 this compromise between the individual components is very 

 different in different cases. In the cell-communities of the series 

 of organisms we find realised a much greater variety of forms of 

 government than we see developed in human society, and it would 



^ [The word " state," as employed in Political Science, carries with it the idea 

 that the association of individuals thus designated is a self-conscious association. 

 (Of. Giddings : The Principles of Sociology, New York, 1896. ) I have thought, 

 therefore, that in the present book the author's term ' 'Zellenntaat " would preferably 

 be translated, not " cell-state," but " cell-community."— F. S. L.] 



2 Of. pp. 79 and 530. 



