Colon Classification (CC): Comprehensive Notes
Colon Classification (CC) is a pioneering system of library classification known for its analytico-synthetic approach. Unlike enumerative schemes that list all possible subjects, CC provides a set of standard units (facets) and connecting symbols to construct class numbers for any subject, making it highly flexible for the ever-growing universe of knowledge.
1. Founder and Genesis
- Founder: Dr. S.R. Ranganathan (Father of Library Science in India).
- Inception Year: 1924 (Great Britain).
- First Published: 1933 (Madras Library Association).
- Inspiration: The idea was conceived in 1924 while Ranganathan was visiting a department store in London. He saw a Meccano set (a toy kit with strips, rods, nuts, and bolts) and realized that a classification scheme could similarly consist of standard units (schedules) connected by symbols (nuts and bolts) to create any shape (class number).
- Workplace/Context: Started during his tenure as Librarian at Madras University Library; later developments continued at the Documentation Research and Training Centre (DRTC), Bangalore.
2. Editions and Timeline
The scheme evolved through seven major editions, transitioning from a rigidly faceted scheme to a freely faceted one.
| Edition | Year | Key Features & Changes |
|---|---|---|
| 1st Edition | 1933 | Three parts (Rules, Schedules, Index). Mixed notation. Colon (:) was the only connecting symbol. Rigidly faceted. |
| 2nd Edition | 1939 | Based on the theory in Prolegomena to Library Classification (1937). Introduced "Octave Principles" and "Auto-bias Device". Added Main Class: Spiritual Experience & Mysticism. |
| 3rd Edition | 1950 | No major modifications; minor terminology changes. |
| 4th Edition | 1952 | Major Turning Point: Introduction of the Five Fundamental Categories (PMEST). Distinct indicator digits were assigned for Personality, Matter, Energy, Space, and Time. Became a "Freely Faceted" scheme. |
| 5th Edition | 1957 | Modifications to rules/schedules. Introduction of second levels for Space and Time facets. |
| 6th Edition | 1960 | Replaced Greek letters with Empty and Emptying digits to simplify notation. (Reprinted in 1963 with amendments). |
| 7th Edition | 1987 | Published posthumously (edited by M.A. Gopinath). Substantial changes; no index included. |
3. Fundamental Categories (PMEST)
Ranganathan postulated that any subject can be analyzed into five fundamental categories. In the 4th edition (1952), specific indicator digits were assigned to each.
- [P] Personality: The core entity or subject (e.g., Human Body in Medicine).
Indicator Digit: , (Comma) - [M] Matter: Material or Property (e.g., Gold in Currency).
Indicator Digit: ; (Semi-colon) - [E] Energy: Action, process, or operation (e.g., Treatment, Diagnosis).
Indicator Digit: : (Colon) - [S] Space: Geographical location.
Indicator Digit: . (Dot) - [T] Time: Chronological period.
Indicator Digit: ' (Apostrophe) *(Originally a dot, changed later)*
4. Notation System
CC uses a Mixed Notation system to ensure infinite hospitality for new subjects.
- Roman Capital Letters (A-Z): Used for Main Classes (e.g., B for Mathematics, L for Medicine).
- Indo-Arabic Numerals (0-9): Used for divisions within facets.
- Roman Lower Case Letters (a-z): Used for common isolates and index.
- Indicator Digits: The punctuation marks ( ; : . ' ) used to connect facets.
- Greek Letters: Used in earlier editions (Delta for Mysticism), later largely replaced.
5. Key Devices and Techniques
To handle complex subjects and ensure flexibility, CC employs several mnemonic devices:
- Chronological Device (CD): Forming a class number using a specific time period (e.g., year of birth of an author).
- Geographical Device (GD): Using geographical location numbers to specify a subject.
- Subject Device (SD): Using the class number of another subject to form a subdivision.
- Alphabetical Device (AD): Using the first letter of a name (e.g., brand names, proper nouns) when no other sequence is logical.
- Empty & Emptying Digits: Used to interpolate new subjects into the existing array without disturbing the sequence.
6. Structure of the Book
The standard Colon Classification book (typically the 6th edition used in academic practice) is divided into three distinct parts:
- Part 1: Rules – Explains the underlying principles, Call Number, Class Number, and grammar of the scheme.
- Part 2: Schedules – Lists the Main Classes and their facets/isolates.
- Part 3: Index – Alphabetical list of subjects with their class numbers (Classics and Sacred Books).
7. The Call Number Structure
In CC, the Call Number identifies a specific book and consists of three elements:
- Class Number: Represents the subject of the book.
- Book Number: Distinguishes books on the same subject (often based on year of publication).
- Collection Number: Indicates if the book belongs to a special collection (e.g., Reference, Rare).