310 OPERATIONS SUBSIDIARY TO INDUCTION. 



Classification. What this principle is, what are its 

 limits, and in what manner Mr. Whewell seems to me 

 to have overstepped them, will appear when we have 

 laid down another and more fundamental rule of 

 Natural Arrangement, entitled to precedency over that 

 which Mr. Whewell has here in view. 



4. The reader is by this time familiar with the 

 general truth (which I restate so often on account of 

 the great confusion in which it is commonly involved) , 

 that there are in nature distinctions of Kind ; distinc- 

 tions not consisting in a given number of definite pro- 

 perties, plus the effects which follow from those pro- 

 perties, but running through the whole nature, through 

 the attributes generally, of the things so distinguished. 

 Our knowledge of the properties of a Kind is never 

 complete. We are always discovering, and expecting 

 to discover, new ones. Where the distinction between 

 things is not one of kind, we expect to find their pro- 

 perties alike, except where there is some reason for 

 their being different. On the contrary, when the dis- 

 tinction is in kind, we expect to find the properties 

 different unless there be some cause for their being the 

 same. All knowledge of a Kind must be obtained by 

 observation and experiment upon the Kind itself; no 

 inference respecting its properties from the properties 

 of things not connected with it by kind, goes for 

 more than the sort of presumption usually charac- 

 terized as an analogy, and generally in one of its 

 fainter degrees. 



Since the common properties of a true Kind, and 

 consequently the general assertions which can be made 

 respecting it, or which are certain to be made here- 

 after as our knowledge extends, are indefinite and 

 inexhaustible; and since the very first principle of 



