Conceptions of Assimilation Reviewed 337 



properties, which electric energy, in certain respects 

 related to it, does not possess. 



If, passing on now to assimilation, we examine the 

 conceptions which the biologists have formed of it, we 

 shall see that their opinions on that subject are quite re- 

 markably concordant. 



Thus, for example, Lewes says: "The peculiarity 

 of vital processes consists in this, that living matter under- 

 goes molecular changes of composition and decomposition 

 which are simultaneous, and by this simultaneity it 

 preserves its integrity of structure." 254 



"Life," remarks in his turn Oscar Hertwig, "mani- 

 fests itself, expressed in the most general terms, in this 

 that the cell, by virtue of its own organization and 

 under the influences of the external world undergoes 

 continual changes and develops forces whereby its organic 

 substance, on the one hand continually destroyed with 

 determined manifestations of energy on the other hand 

 is regenerated." "The life process depends then, on a 

 continual destruction and reformation of organic sub- 

 stance." 255 



But the clearest and most suggestive of all is Claude 

 Bernard in the following celebrated passage : 



"The characteristics of life considered in their essence 

 and in their entirety can be classed in two groups." 



"i. The phenomena of consumption, of vital de- 

 struction, which correspond to the functional phenomena 

 of the organism." 



"2. Plastic phenomena or phenomena of vital crea- 



2B4 Lewes : The Physical Basis of Mind. P. 5. 

 2BB Oscar Hertwig: Die Zelle und die Gewebe. Bd. I, P. 54, and 

 Bd. II, P. 190191. 



