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NAMES AND PROPOSITIONS. 



4. Although the first kind of imperfect definition, 

 (which defines a connotative term by a part only of what it 

 connotes, but a part sufficient to mark out correctly the 

 boundaries of its denotation,) has been considered by the 

 ancients, and by logicians in general, as a complete defi- 

 nition ; it has always been deemed necessary that the attri- 

 butes employed should really form part of the connotation ; for 

 the rule was that the definition must be drawn from the essence 

 of the class ; and this would not have been the case if it had 

 been in any degree made up of attributes not connoted by the 

 name. The second kind of imperfect definition, therefore, in 

 which the name of a class is defined by any of its accidents, 

 that is, by attributes which are not included in its connota- 

 tion, has been rejected from the rank of genuine Definition 

 by all logicians, and has been termed Description. 



This kind of imperfect definition, however, takes its rise 

 from the same cause as the other, namely, the willingness 

 to accept as a definition anything which, whether it expounds 

 the meaning of the name or not, enables us to discriminate the 

 things denoted by the name from all other things, and conse- 

 quently to employ the term in predication without deviating 

 from established usage. This purpose is duly answered by 

 stating any (no matter what) of the attributes which are 

 common to the whole of the class, and peculiar to it ; or any 

 combination of attributes which happens to be peculiar to it, 

 though separately each of those attributes may be common to 

 it with some other things. It is only necessary that the defi- 

 nition (or description) thus formed, should be convertible with 

 the name which it professes to define ; that is, should be 

 exactly co-extensive with it, being predicable of everything of 

 which it is predicable, and of nothing of which it is not pre- 

 dicable ; though the attributes specified may have no con- 

 nexion with those which mankind had in view when they 

 formed or recognised the class, and gave it a name. The fol- 

 lowing are correct definitions of Man, according to this test : 

 Man is a mammiferous animal, having (by nature) two hands 

 (for the human species answers to this description, and no 



