ARISTOTLE'S BIOLOGY 



constantly seeking an order of progression 

 corresponding to the excellence and amplitude 

 of the equipment of each group of animals. 

 The opening description, or division, of the 

 parts of animals is so reduced to its simplest 

 terms, and therefore so abstract that effort is 

 needed to perceive its significance. 



" Of the parts of animals some are simple: 

 to wit, all such as divide into parts uniform 

 with themselves, as flesh into flesh; others are 

 composite, such as divide into parts not uni- 

 form with themselves, as, for instance, the 

 hand does not divide into hands nor the face 

 into faces." This distinction held good in 

 Aristotle's time as now; 27 but the depth of its 

 validity has been plumbed only through modern 

 microscopic study of cells and tissues. 



So in regard to the classification of animals 

 by genera and species which may be drawn 

 from his writings. Altogether Aristotle refers 

 to about five hundred and forty animals of all 

 kinds, including insects; and yet modern 

 zoology, recognizing more nearly one million 

 species, largely preserves his classification. 



The attribute of soul or life and the degree 

 and kinds of its efficient presence are with 

 Aristotle the criterion of excellence in living 



[45] 



