[Thus, when I say "Some soldiers of the Tenth Regiment are tall," or "The soldiers of the Tenth Regiment are brave," I am using the Name "soldiers of the Tenth Regiment" in the _first_ sense; and it is just the same as if I were to point to each of them _separately_, and to say "_This_ soldier of the Tenth Regiment is tall," "_That_ soldier of the Tenth Regiment is tall," and so on. But, when I say "The soldiers of the Tenth Regiment are formed in square," I am using the phrase in the _second_ sense; and it is just the same as if I were to say "The _Tenth Regiment_ is formed in square."] pg006 CHAPTER V. _DEFINITIONS._ It is evident that every Member of a _Species_ is _also_ a Member of the _Genus_ out of which that Species has been picked, and that it possesses the _Differentia_ of that Species. Hence it may be represented by a Name consisting of two parts, one being a Name representing any Member of the _Genus_, and the other being the _Differentia_ of that Species. Such a Name is called a '=Definition=' of any Member of that Species, and to give it such a Name is to '=define=' it. [Thus, we may define a "Treasure" as a "valuable Thing." In this case we regard "Things" as the _Genus_, and "valuable" as the _Differentia_.] The following Examples, of this Process, may be taken as models for working others. [Note that, in each Definition, the Substantive, representing a Member (or Members) of the _Genus_, is printed in Capitals.] 1. Define "a Treasure." _Ans._ "a valuable THING." 2. Define "Treasures." _Ans._ "valuable THINGS." 3. Define "a Town." _Ans._ "a material artificial THING, consisting of houses and streets." pg007 4. Define "Men." _Ans._ "material, living THINGS, belonging to the Animal Kingdom, having two hands and two feet"; or else "ANIMALS having two hands and two feet." 5. Define "London." _Ans._ "the material artificial THING, which consists of houses and streets, and has four million inhabitants"; or else "the TOWN which has four million inhabitants." [Note that we here use the article "the" instead of "a", because we happen to know that there is only _one_ such Thing. The Reader can set himself any number of Examples of this Process, by simply choosing the Name of any common Thing (such as "house," "tree," "knife"), making a Definition for it, and then testing his answer by referring to any English Dictionary.] pg008 BOOK II. PROPOSITIONS. CHAPTER I. _PROPOSITIONS GENERALLY._ § 1. _Introductory._ Note that the word "some" is to be regarded, henceforward, as meaning "one or more."