312 OPERATIONS SUBSIDIARY TO INDUCTION. 



In so far as a natural classification is grounded 

 upon real Kinds, its groups are certainly not conven- 

 tional; Mr. Whewell is quite right in affirming that 

 they do not depend upon an arbitrary choice of the 

 naturalist. But it does not follow, nor, I conceive, 

 is it true, that these classes are determined by a type, 

 and not by characters. To determine them by a type 

 would be as sure a way of missing the Kind, as if we 

 were to select a set of characters arbitrarily. They 

 are determined by characters, but which are not 

 arbitrary. . The problem is, to find a few definite 

 characters which point to the multitude of indefinite 

 ones. Kinds are Classes between which there is an 

 impassable barrier; and what we have to seek is, 

 marks whereby we may determine on which side of 

 the barrier an object takes its place. The characters 

 which will best do this are what should be chosen : if 

 they are also important in themselves, so much the 

 better. When we have selected the characters, we 

 parcel oat the objects according to those characters, 

 and not, as Mr. Whewell seems to suppose, according 

 to resemblance to a type. We do not compose the 

 species Ranunculus acris, of all plants which bear a 

 satisfactory degree of resemblance to a model-butter- 

 cup, but of those which possess certain characters 

 selected as marks by which we might recognise the 

 possibility of a common parentage ; and the enumera- 

 tion of those characters is the definition of the species. 



The question next arises, whether, as all Kinds 

 must have a place among the classes, so all the classes 

 in a natural arrangement must be Kinds ? And to 

 this I answer, certainly not. The distinctions of Kind 

 are not numerous enough to supply the whole basis 

 of a classification. Very few of the genera of plants, 

 or even of the families, can be pronounced with cer- 



