434 OPERATIONS SUBSIDIARY TO INDUCTION. 



which the Liniiaean classification serves is that of causing us to re- 

 member, better than we should otherwise have done, the exact number 

 of stamens and pistils of every species of plants. Now, as this prop- 

 erty is of little importance or interest, the remembering it with any 

 particular accm-acy is of no moment. And inasmuch as, by habitually 

 thinking of plants in those groups, we are prevented from habitually 

 thinking of them in groups which have a greater number of projierties 

 in common, the effect of such a classification, when systematically 

 adhered to, upon our habits of thought, must be regarded, as mis- 

 chievous. ' 



The ends of scientific classification are best answered, when the 

 objects are formed into groups respecting which a greater number of 

 general propositions can be made, arid those propositions more impor- 

 tant, than could be made respecting any other gi'oups into which the 

 same things could be distributed. The properties, therefore, according 

 to which objects are classified, shoidd, if possible, be those which are 

 causes of many other properties ; or at any rate, which are sure marks 

 of them. Causes are preferable, both as being the surest and most 

 direct of marks, and as being themselves the properties upon which it 

 is of most use that our attention should be strongly fixed. But the 

 property which is the cause of the chief peculiarities of a class, is 

 unfortunately seldom fitted to serve also as the diagnostic of the class. 

 Instead of the cause, we must generally select some of its more prom- 

 inent effects, which may serve as marks of the other effects and of the 

 cause itself. 



A classification thus formed is properly scientific or philosophical, 

 and is commonly called a Natural, in contradistinction to a Technical 

 or Artificial, classification or aiTangement. The phrase Natural Clas- 

 sification seems most peculiarly appropriate to such an'angements as 

 con-espond, in the groups which they fonn, to the spontaneous tenden- 

 cies of the mind, by placing together the objects most similar in their 

 general aspect ; in opposition to those technical systems which, ar- 

 ranging things according to their agreement in some circumstance 

 arbitrarily selected, often throw into the same group objects which in 

 the general aggi'egate of their properties present no resemblance, and 

 into different and remote groups, others which have the closest simi- 

 larity. It is one of the most valid recommendations of any classifica- 

 tion to the character of a scientific one, that it shall be a natural 

 classification in this sense also ; for the test of its scientific character is 

 the number and importance of the jjroperties which can be asserted in 

 common of all objects included in a group ; and propertieson which 

 the general aspect of the things depends, are, if only on that ground, 

 important, as well as, in most cases, numerous. But, though a strong 

 recommendation, this circumstance is not a sine qud non ; since the 

 more obvious properties of things may be of ti-ifling importance com- 

 pared with others that are not obvious. I have seen it mentioned as a 

 great absurdity in the LinnEean classification, that it places (which by 

 the way it does not) the violet by the side of the oak : it certainly dis- 

 severs natural afiinities, and brings together things quite as unlike as 

 the oak and the violet are. But the difference, apparently so wide, 

 which renders the juxtaposition of those two vegetables so suitable an 

 illustration of a bad aiTangement, depends, to the common eye, mainly 

 upon mere size and texture ; now if we made it our study to adopt 



