CLASSIFICATION. 267 



those groups in such an order, as will best conduce to the 

 remembrance and to the ascertainment of their laws. 



Classification thus considered, differs from classification in 

 the wider sense, in having reference to real objects exclusively, 

 and not to all that are imaginable : its object being the clue 

 co-ordination in our minds of those things only, with the 

 properties of which we have actually occasion to make our 

 selves acquainted. But, on the other hand, it embraces all 

 really existing objects. We cannot constitute any one class 

 properly, except in reference to a general division of the 

 whole of nature ; we cannot determine the group in which any 

 one object can most conveniently be placed,, without taking 

 into consideration all the varieties of existing objects, all at 

 least which have any degree of affinity with it. No one 

 family of plants or animals could have been rationally con 

 stituted, except as part of a systematic arrangement of all 

 plants or animals ; nor could such a general arrangement have 

 been properly made, without first determining the exact place 

 of plants and animals in a general division of nature. 



2. There is no property of objects which may not be 

 taken, if we please, as the foundation for a classification or 

 mental grouping of those objects; and in our first attempts 

 we are likely to select for that, purpose properties which are 

 simple, easily conceived, and perceptible on a first view, 

 without any previous process of thought. Thus Tournefort s 

 arrangement of plants was founded on the shape and divisions 

 of the corolla ; and that which is commonly called the Lin- 

 nsean (though Linnseus also suggested another and more 

 scientific arrangement) was grounded chiefly on the number 

 of the stamens and pistils. 



But these classifications, which are at first recommended 

 by the facility they afford of ascertaining to what class any 

 individual belongs, are seldom much adapted to the ends of 

 that Classification which is the subject of our present remarks. 

 The Linnasan arrangement answers the purpose of making 

 us think together of all those kinds of plants which possess 

 the same number of stamens and pistils ; but to think of them 



