Aristotle's biology 



individual animal, it must direct and mould 

 the growth and character of every part. 

 Aristotle holds this creed, and devotes the De 

 Partibus Animalium to its special illustration. 



First he shows it generally in regard to the 

 animal's component parts. The homogeneous 

 fluids and tissues exist for the sake of the more 

 especially active parts or organs,*' like the eye 

 or hand. They must possess the different 

 properties, like fluidity, softness, or hardness, 

 required by the organ, and of which it will 

 present a combination. " For the hand . . . 

 requires one property to enable it to effect 

 pressure, and another and different property 

 for simple prehension. For this reason the 

 active or executive parts of the body are com- 

 pounded out of bones, sinews, flesh and the like, 

 but not these latter out of the former." And 

 the relations between these two orders of 

 parts are determined by a final cause,*^ which 

 is the life of the whole animal. 



Aristotle will not flinch from the principle 

 that this final end, the life of the whole animal, 

 calls every part into being. It is irrational 

 to hold the reverse, i.e., that the character or 

 mechanical power of a part produces or de- 

 termines that final end which is the life or 



[67] 



