Differentia

Abstract: IN ARISTOTLE'S WRITINGS the re a re at least t h r ee accoun t s o f the n a t u r e o f g e n u s a n d d i f fe ren t ia . T h e s e accoun t s m a y be briefly desc r ibed in these te rms: (I) g e n u s a n d d i f f e r en t i a a re radical ly dist inct in cha rac te r , a n d the genus is the m o r e i m p o r t a n t e l e m e n t in the def in i t ion; ( I I ) g e n u s a n d d i f fe r ent ia a re ve ry similar in c h a r a c t e r a n d i m p o r t a n c e ; ( I I I ) g e n u s a n d d i f f e r en tia are s imilar in cha rac te r , bu t the d i f f e r en t i a is the m o r e i m p o r t a n t e l e m e n t in the def in i t ion . T h e s e accoun t s r ep re sen t , I believe, t h r ee stages in the d e v e l o p m e n t o f Aris tot le ' s t h o u g h t . I n this p a p e r I shall e x a m i n e each acc o u n t a n d expla in , at least in par t , w h y Aris tot le a d o p t s them.