DEFINITION. 155 



other animal does) : Man is an animal who cooks his food : 

 Man is a featherless biped. 



What would otherwise be a mere description, may be 

 raised to the rank of a real definition by the peculiar purpose 

 which the speakef or writer has in view. As was seen in the 

 preceding chapter, it may, for the ends of a particular art or 

 science, or for the more convenient statement of an author's 

 particular doctrines, be advisable to give to some general name, 

 without altering its denotation, a special connotation, different 

 from its ordinary one. When this is done, a definition of the 

 name by means of the attributes which make up the special 

 connotation, though in general a mere accidental definition or 

 description, becomes on the particular occasion and for the 

 particular purpose a complete and genuine definition. This 

 actually occurs with respect to one of the preceding examples, 

 " Man is a mammiferous animal having two hands," which is 

 the scientific definition of man, considered as one of the species 

 in Cuvier's distribution of the animal kingdom. 



In cases of this sort, though the definition is still a decla- 

 ration of the meaning which in the particular instance the 

 name is appointed to convey, it cannot be said that to state 

 the meaning of the word is the purpose of the definition. The 

 purpose is not to expound a name, but a classification. The 

 special meaning which Cuvier assigned to the word Man, 

 (quite foreign to its ordinary meaning, though involving 

 no change in the denotation of the word,) was incidental to a 

 plan of arranging animals into classes on a certain principle, 

 that is, according to a certain set of distinctions. And since 

 the definition of Man according to the ordinary connotation of 

 the word, though it would have answered every other purpose 

 of a definition, would not have pointed out the place which the 

 species ought to occupy in that particular classification ; he 

 gave the word a special connotation, that he might be able to 

 define it by the kind of attributes on which, for reasons of 

 scientific convenience, he had resolved to found his division of 

 animated nature. 



Scientific definitions, whether they are definitions of scien- 

 tific terms, or of common terms used in a scientific sense, are 



