284 ELEMENTS OF SCIENCE 



consequently is an art as well as a science it is the art 

 of correct thinking and of valid inference. 



The science of logic, as " the science of the forms of 

 thought," is divisible into three parts, each of which 

 deals with one class of such forms. The first part deals 

 with conceptions, the second with judgments, and the 

 third with reasoning. 



The first part which thus deals with " conceptions," is 

 also said to be occupied about names, or terms. This 

 is said on account of the intimate association which 

 exists between each thought, or verbum mentale, and the 

 word which signifies it, or verbum oris.* The connection 

 is so close that we may henceforth, in this chapter, deal 

 with the spoken and written signs of thoughts as if they 

 were the very thoughts themselves ; although it should 

 nevertheless be remembered that we are not treating of 

 names as such, but as symbols of the thoughts they 

 represent. 



A "name," or "term," is a human, conventional articu- 

 late sound, used with an intention of signifying something. 

 There are various kinds of names. They may be (T) 

 universal applicable to each and all of a class of objects, 

 e.g., "man," "true," &c. ; (2) collective applicable to a 

 whole but not to its component members, e.g., " army"; 

 (3) particular applicable to but a portion of some whole, 

 e.g., " some Indians " ; (4) singular applicable to one 

 only, e.g., " Julius Caesar " ; (5) universal having the 

 same signification when applied to different objects, e.g., 

 "green," as applied to foliage and a lady's dress; (6) 

 equivocal one sound having more than one signification, 

 e.g., "box"; (7) analogous when one signification 

 applies in an unequal degree to different objects. Such 



* See ante, p. 277. 



