132 THE SCIENCE OF LOGIC. 



system of names for the groups, of which the classification con 

 sists ; and (b] a set of terms for describing the nature and char 

 acteristics of the individual objects composing those groups. The 

 former collection constitutes what is technically known as Scien 

 tific Nomenclature, the latter what is known as Scientific 

 Terminology. 



[a] The interaction between thought and language is close 

 and constant (22). Accordingly, it is only in such sciences as 

 zoology, botany, and chemistry, where classification has been 

 carried out more or less completely, that anything like an ade 

 quate nomenclature is to be found. 



As one and the same individual object may enter into 

 several different artificial classifications, it might in the abstract 

 be considered an advantage to have a different class name for it 

 in every such system ; but as a matter of fact such advantage 

 would be much more than counterbalanced by the endless 

 confusion that would arise from having several names for the 

 same object. The practical needs of life demand that as far as 

 possible one and the same object should be referred to by only 

 one name. Hence, special names are not usually sought, for the 

 groups of every ephemeral artificial classification ; while, for the 

 popular, rough and ready classification of things, based on their 

 broad resemblances, we have the existing nomenclature in which 

 these classes are already embodied and expressed in ordinary 

 language. But when the scientific study of the things of any 

 particular department minerals, plants, animals leads to a much 

 more complex and comprehensive classification than that which 

 satisfies popular needs, then we must aim at helping, our memory 

 of these numerous classes, and of their relations to one another, 

 by fixing upon them names expressive of these relations. 



Endeavouring to accomplish this purpose, we usually start 

 with the existing names which we find in ordinary language for 

 the highest, the lowest, and certain intermediate, broadly-marked 

 classes or with as many of these names as will suit our purpose, 

 and we may form names for the new classes in either of two ways. 



(i) We may, as in zoology and botany, combine the name of 

 the higher class with a term descriptive of some distinctive attri 

 bute, in order to form the name of the next lower class. 



On the assumption that the connotation and definition of terms, though 

 to a certain extent conventional, should nevertheless aim at &quot; following nature,&quot; 

 in the sense of embodying the most fundamental and important attributes of 



