THE FINAL SYSTEM: GALEN 



is directed by Nature; for those which are 

 distended by us undergo this distension in one 

 direction but grow less in the others. . . . Thus 

 Nature alone has the power to expand a body in 

 all directions so that it remains unruptured 

 and preserves completely its previous form." 



As for nutrition, the third of these great 

 faculties: "When the matter which flows to 

 each part of the body in the form of nutri- 

 ment is being worked up into it, this activity 

 is nutrition, and its cause is the nutritive 

 faculty. Of course, the kind of activity here 

 involved is also an alteration, but not like that 

 occurring in the stage of genesis. For in 

 [genesis] something comes into existence which 

 did not exist previously, while in nutrition the 

 inflowing material becomes assimilated to that 

 which has already come into existence. There- 

 fore the former kind of alteration has been 

 termed genesis and the latter assimilation." "^ 



Nowadays this description would be supple- 

 mented, or superseded, by a description of the 

 multiplication of the body-cells in the growth 

 of tissue, both extra- and intra-uterine, — 

 which we perceive and can to some extent de- 

 scribe, but still cannot account for, save as a 

 power of nature. 



[115] 



