=B. Division of Known Classes.=--A second common mode of developing new concepts in school work is in breaking up larger classes into co-ordinate sub-classes. This, of course, involves the developing of new concepts to cover these sub-classes. In such cases, however, the new notions are merely modified forms of the higher class notion. When, for example, the pupil gains general notions representative of the classes, proper noun and common noun, the new terms merely add something to the intension of the more extensive term noun. This will be evident by considering the difference between the notions noun and proper noun. Both agree in possessing the attribute _used to name_. The latter is more intensive, however, because it signifies _used to name a particular object_. Although in such cases the lesson seems in a sense to develop new general notions, they represent merely an adding to the intension of a notion already possessed by the child. =Use of the Term.=--A further problem regarding the process of conception concerns the question of the significance of a name. When a person uses such a term as dog, whale, hepatica, guava, etc., to name a certain object, what is the exact sense, or meaning, in which the name is to be applied? A class name, when applied scientifically to an object, is evidently supposed to denote the presence in it of certain essential characteristics which belong to the class. It is clear, however, that the ordinary man rarely uses these names with any scientific precision. A man can point to an object and say that it is a horse, and yet be ignorant of many of the essential features of a horse. In such cases, therefore, the use of the name merely shows that the person considers the object to belong to a certain class, but is no guarantee that he is thinking of the essential qualities of the class. It might be said, therefore, that a class term is used for two somewhat different purposes, either to denote the object merely, or to signify scientifically the attributes possessed by the object. It is in the second respect that danger of error in reasoning arises. So far as a name represents the attributes of a class, it will signify for us just those attributes which we associate with that class. So long, therefore, as the word fish means to us an animal living in the water, we will include in the class the whale, which really does not belong to the class, and perhaps exclude from the class the flying fish, although it is scientifically a member of the class. THE DEFINITION