The design and development of schemes of Library Classification are guided by comprehensive theoretical frameworks, such as those established by S.R. Ranganathan, which organize the complex Universe of Subjects into a systematic order. Separately, the concept of a Standard Sub-division Index refers to the use of standardized auxiliary tables for recurring concepts across disciplines, exemplified prominently in schemes like DDC.
I. Design and Development of Schemes of Library Classification
The development of classification schemes has progressed through distinct historical and theoretical stages, moving from empirical, enumerative approaches to dynamic, analytico-synthetic systems guided by normative principles.
Theoretical Foundation and Stages
The General Theory of Library Classification, revolutionized by S.R. Ranganathan, is instrumental in guiding scheme design. This theory addresses the fundamental problem of transforming the multi-dimensional universe of knowledge into a one-dimensional (linear) sequence.
- Stage 1: Descriptive Theory (Pre-1950s): This stage saw the emergence of theories distilled from existing practices. Schemes were based on the "flair or natural gift of the designers and not on any objectively worked out theory". Contributors included Brown, Richardson, Hulme, and Sayers.
- Stage 2: Dynamic Theory (Ranganathan): Ranganathan formulated this theory, guided by Basic Laws, Laws of Library Science, Canons, Principles, and Postulates, to guide the design of schemes with greater detail.
Normative Principles and Methodology
The scientific methodology for designing classification schemes is systematized into three planes of work:
- Idea Plane (Thinking/Policy): This plane deals with the intellectual analysis of the Universe of Subjects (UoS), focusing on its structure, dimensions, qualities, and relationships. The canons here ensure the characteristics chosen for division are easily differentiated, ascertainable, relevant, and permanent. A scheme of library classification must first enumerate the Universe of Subjects, state their interrelations, and fix their order in the idea plane.
- Verbal Plane (Terminology/Language): This plane involves representing the findings of the Idea Plane in terms, ensuring terminology is current, context-specific, and non-critical, and avoiding homonyms and synonyms.
- Notational Plane (Symbols/Mechanism): This plane transforms the terms into an artificial language of ordinal numbers (notation) to mechanize arrangement. The canons here ensure qualities like hospitality (to accommodate new classes), expressiveness (reflecting hierarchy), and brevity. The notation must be the faithful executor of the idea plane.
Application of Postulates (Faceted Design)
In designing schemes, particularly faceted classifications (like Colon Classification, CC), the application of Postulates and Principles is critical.
- Five Fundamental Categories (FCs): Ranganathan postulated that every subject is constituted by the Five Fundamental Categories (PMEST)—Personality, Matter, Energy, Space, and Time.
- Facet Sequence Principles: Principles like the Wall-Picture Principle guide the sequencing of facets (components) when synthesizing a class number.
- Helpful Sequence Principles: These principles guide the arrangement of isolates within an array to ensure the sequence is helpful to users (e.g., Principle of Later-in-Time, Principle of Alphabetical Sequence).
II. Standard Sub-Division Index / Common Isolates
The concept of standardized auxiliary schedules for common subdivisions is crucial for achieving economy, consistency, and mnemonic value in classification schemes. These recurring concepts are known as Common Isolates or Standard Subdivisions.
Nature and Purpose
Common isolates are certain kinds of concepts that keep recurring and may be found in many subjects, such as proceedings, periodical, dictionary, or encyclopedia. They represent inner and outer forms of presentation and historical and geographical treatment.
The purpose of standardizing these recurring concepts is multifaceted:
- Economy: Standardization restricts the length of the schedules by listing these common features only once, resulting in economy of size.
- Mnemonic Value: Standardization lends mnemonic value to the recurring concepts, as they are consistently expressed by the same set of symbols.
- Synthesis: These schedules allow for the synthesis or number building of detailed class numbers by adding common concepts to specific subjects.
Historical Development in DDC and UDC
The concept of common isolates was first introduced by Melvil Dewey:
DDC (Dewey Decimal Classification): Dewey first called them form divisions in the second edition of DDC (1885).
- The expansion of DDC's capability to express complex topics has been achieved through auxiliary tables (T1-T7) and 'divide like' devices.
- Table 1: Standard Subdivisions (T1) is the core table listing these general concepts.
- Table 2: Geographic Areas, Historical Periods, Persons (T2) is another example of a common auxiliary used across subjects.
UDC (Universal Decimal Classification): In UDC, common isolates are called auxiliary subdivisions.
- UDC utilizes Common Auxiliaries (universally applicable) and Special Auxiliaries (locally recurrent characteristics), providing a robust system for synthesis.
- Space and time isolates are treated as common auxiliaries and listed separately.
CC and Common Isolates
In Colon Classification (CC), Ranganathan's scheme, three different schedules for common subdivisions were provided in the first edition, later evolving into detailed schedules for the Fundamental Categories Space [S] and Time [T]. CC also includes notations for common subdivisions such as bibliographies, statistics, and collected works. The application of a digit for a special Common Subdivision specific to a class (like criticism in Literature) is also provided.