Levels of categorization

Cognitive categories are organized into taxonomies - specifically folk taxonomies, which are in turn organized into levels of categorization.

Folk taxonomies, like all other taxonomies, are based on class inclusion and degree of generality. The former implies that units in the taxonomy are included under units further up the taxonomy, while the latter implies that the further up in the taxonomy a unit is located, the more general it is and the further down it is place the more specific it is.

Class inclusion and degree of specificity manifest themselves in three levels of categorization - namely the superordinate level, the basic level and the subordinate level.

Superordinate level categories
Superordinate categories are found at the top of a folk taxonomy. They display a high degree of generality and provide only very abstract information, which are sometimes called category-wide attributes. They do not provide any specific gestalt or configuration of properties. Superordinate categories display a low degree of inclusion and include basic level categories.

Basic level categories
The categories at the basic level, or generic level, the most culturally salient and have the most basic cognitive functions. It is at this level that the differences between entities are perceived, because categories at this level provide generic recognizable gestalts, in the sense that it is at this level that the most comon idealization of features of a category is found. In other words, the most relevant conceptual information relating to a category is stored at the basic level.

Basic level categories, which are included under superordinate level categories, display higher class inclusion than subordinate level categories, having more members than superordinate categories. However, superordinate categories display a higher degree of generality.

Subordinate level categories
Subordinate level categories display low degree of generality and a low degree of class inclusion. They have clearly identifiable and higly detailed gestalts as well as numerous individuating specific features. Subordinate level categories are included under basic level categories.

Planes, trains and automobiles
The concept CAR is a basic level category. It provides a very basic gestalt - the outline of a typical shape of a car - with no no details as such. The concept CAR is a member of the category VEHICLE, which is not very specific. It does not have any specific configuration of attributes other than it is USED IN ORDER TO TRANSPORT PEOPLE AND OBJECTS. There are several other concepts fitting this description such as TRAIN, PLANE, BOAT, TANK and so on. These are all basic level categories that are included under the superordinate level category VEHICLE and they all provide shapes and configurations of properties that set them apart from each other. The category CAR includes a plethora of different kinds of car such as STATION CAR, SPORTS CAR, LIMO, OFFROADER, JEEP, VAN, MINIBUS, etc., as well as a large host of brands and models based on ocation of production and so on. All of these subordinate level categories.

VEHICLE                               Superordinate |                                 level |           |         |         |         |     |        TRAIN       PLANE       CAR      BOAT      TANK   ... Basic |                                level -       |          |         |        |         |   |      |     |  STATION CAR  SPORTS CAR   LIMO   OFFROADER  JEEP VAN MINI BUS ... Subordinate level