CLASSIFICATION AND THE PREDICABLES. 165 



in connexion with the exploded tenets of the Realists ; 

 and what the schoolmen chose to call the essence of 

 an individual, was simply the essence of the class to 

 which that individual was most familiarly referred. 



Is there no difference, then, except this merely 

 verbal one, between the classes which the schoolmen 

 admitted to be genera or species, and those to which 

 they refused the title ? Is it an error to regard some 

 of the differences which exist among objects as dif- 

 ferences in kind (genere or specie), and others only as 

 differences in the accidents? Were the schoolmen 

 right or wrong in giving to some of the classes into 

 which things may be divided, the name of kinds, and 

 considering others as secondary divisions, grounded 

 upon differences of a comparatively superficial nature ? 

 Examination will show that the Aristotelians did mean 

 something by this distinction, and something im- 

 portant ; but which, being but indistinctly conceived, 

 was inadequately expressed by the phraseology of 

 essences, and by the various other modes of speech to 

 which they had recourse. 



4. It is a fundamental principle in logic, that the 

 power of framing classes is unlimited, as long as there 

 is any (even the smallest) difference to found a dis- 

 tinction upon. Take any attribute whatever, and if 

 some things have it, and others have not, we may 

 ground upon the attribute a division of all things into 

 two classes ; and we actually do so, the moment we 

 create a name which connotes the attribute. The 

 number of possible classes, therefore, is boundless ; 

 and there are as many actual classes (either of real or 

 of imaginary things) as there are general names, posi- 

 tive and negative together 



But if we contemplate any one of the classes so 



