Formal Logic (General logic) 3: Operation of a concept: definition, division, restriction, and Generalization

Definition

Concept definition: Uses refined statements to display the connotation of a concept, that is, to reveal the special or essential attributes of the object reflected by the concept.

Definitions can be divided into substantive definitions and word definitions.

Substantive definitions reveal the inherent or essential attributes of objects. The basic method is:

Defined concept = concept + specificity; that is, after generalization (specificity), limit (specificity ).

Substantive definitions can also be divided:

Nature definition: reveals the definition of the nature of the object reflected by the concept.

Definition: reveals the generation or formation process of objects reflected by concepts.

Function Definition: reveals the definition of the function or function of an object reflected by a concept.

Relationship definition: reveals the definition of the relationship between objects and other objects.

Definitions reveal (describe or stipulate) the meaning of words, just similar to definitions. Including:

Description definition: Describes the defined meaning. For example, "zookeeper" indicates 80 or 90 years old.

Definition of a specified word: defines the meaning of a word that is not yet certain. For example, "four modernization" and "one country, two systems"

Defined rules:

The extension of the definition item and the defined item should be the same. Violation of this rule may result in "too wide definition" or "too narrow definition ".

The defined items cannot directly or indirectly include the defined items. Otherwise, a logical error of "simultaneous repetition" or "loop definition" may occur.

Definition items cannot contain ambiguous words, and cannot be compared. Violation of this rule may result in a "ambiguous definition" or "representative definition by analogy" error.

The definition cannot be negative. Violating this rule will lead to a "negative definition" error.

Concept Division

Division: it refers to the logical method for defining the extension of a concept by dividing it into several concepts based on certain attributes of an object. The Division consists of the parent item, subitem, and basis.

The criteria for Division refer to one or some attributes of the objects on which the Division is based.

The difference between division and decomposition: Division refers to dividing a concept into several types of concepts, which dismember a specific thing into many components.

The layers can be divided into one division (one layer) and continuous Division (multiple layers ).

The number of sub-items can be divided into two categories: Binary Division and multi-Division.

The basic attributes of objects can be divided into scientific and general attributes.

The Division should comply with the following rules:

The Division must be commensurate. Logical errors that violate this rule, or "incomplete division", or "extra sub-item ".

The allocated sub-items must be mutually exclusive; otherwise, a logical error of "sub-item compatibility" may occur.

Each division must follow the same standard. Violating this rule will lead to a logical error of "different standards.

The Division should be conducted step by level. Violating this rule will lead to a logical error of "unclear levels" or "excessive levels of division.

Restrictions and generalization of concepts

There is a inverse relationship between the connotation and extension of a concept: the larger the extension, the less the connotation; the less the extension, the more connotation Yu.

The limitation of a concept refers to narrowing down its extension by adding a conceptual connotation. A restriction refers to the transition from a concept of kinship to its concept of species. The concept is the limit.

A general concept refers to extending the concept by reducing its connotation. Generally, the concept of species is transitioned to the concept of family. Philosophical category is the ultimate of generalization.

For example, "Workers" can be summarized as "people" and can be limited to "Textile Workers ".