: DEFINING-ATTRIBUTE THEORIES OF CONCEPTS • The meaning of a concept can be captured by a conjunctive list of attributes (i.e., a list of attributes connected by ANDs). • These attributes are atomic units or primitives which are the basic building blocks of concepts. • Each of these attributes is necessary and all of them are jointly sufficient for something to be identified as an instance of the concept. • What is and is not a member of the category is clearly defined; thus, there are clear-cut boundaries between members and non-members of the category. • All members of the concept are equally representative. • When concepts are organised in a hierarchy then the defining attributes of a more specific concept (e.g., sparrow) in relation to its more general relative (Its superordinate; e.g., bird) includes all the defining attributes of the superordinate. : CONCEPT HIERARCHIES • People use hierarchies to represent relationships of class inclusion between categories; ...