1. Melvil Dewey’s Ingenious Notational System North American Symposium on Knowledge Organization June 19, 2009 Rebecca Green Dewey Decimal Classification

2. Roadmap Shelf arrangement vs. subject collocation Decimal notation Hierarchical organization Number building Language-independent representation Potential for customization

3. Shelf arrangement in the 1800s Institution-specific, using, e.g., accession order, broad subject classes, size, author name Duplication of effort Initial classification Reclassification

4. Eureka! The insight Use classification scheme to establish relatively fine-grained subject representation Use decimal notation to govern order of shelf arrangement Immediate benefits derived from the insight Institution-independent relative location Cooperative classification Linear sequence + hierarchical organization

5. OSI model applied to shelf arrangement Shelf arrangement as bottom/physical layer of model Each layer provides services to layer above Support access to / use of intellectual/artistic content of collection as top/application layer of model

6. Decimal notation (1) DDC 1,1876 Every class admitted of division into 9 subclasses (represented 1-9), plus 0 to represent no division “No difficulty found in... omitting the initial zero;” some 2-digit numbers (e.g., 51 [051]) Also some 4-digit numbers (e.g., 5545 [554.5]) Notation incorporated decimal point “as if it were written after the first figure”

7. Decimal notation (2) DDC 2, 1885 Leading zeroes retained Decimal point between third and fourth digits Effect Notation more expressive Filing order same whether interpreted numerically or alphanumerically

8. Hierarchical organization (1) New subjects can be accommodated by notational expansion, e.g., 005.75 Specific types of data files and databases 005.753Temporal, spatial, constraint databases

9. Hierarchical organization (2) Interoperable expansions 2—455 5Pisa province (Eng) Provincia di Pisa (It) 2—455 51 Pisa (Eng) Comune di Pisa (It) 2—455 52 Nordovest della provincia di Pisa (It) 2—455 523 San Guiliano Terme (It)

10. Hierarchical organization (3) Flexible granularity 320.5Political ideologies 320.53* Collectivism and fascism 320.532 Communism 320.532 2 Marxism-Leninism * Abridged edition stops here

11. Hierarchical organization (4) Expressivity of notation Specificity Psychology 150 Emotions of children 155.4124 Relationships among subjects Oats 633.13 Rye 633.14 Corn 633.15 Barley 633.16

12. Number building (1) Mnemonicity China T2—51, 951 Chinese language T6—951, 495.1 Chinese literature 895.1 Chinese religions 299.51 Chinese Communist Party 324.251075 Chinese calendar 529.32951

13. Number building (2) Intrafacet relationships Ceramic arts of Jews 738.089924 738 Ceramic arts 089 Ethnic and national groups (from Table 1) 924 Jews (from Table 5 as instructed under T1—08905-T1—08999: Add to base number T1—089 notation T5—05-T5—9 from Table 5)

14. Number building (3) Intrafacet relationships—cont. French masters 759.4074 759 (Painting and paintings) Historical, geographic, persons treatment 4France (from Table 2, as instructed at 759.3-759.8 Miscellaneous parts of Europe: Add to base number 759 the numbers following –4 in notation 43-48 from Table 2) 074 Exhibitions (from Table 1)

15. Language-independent representation (1) 713 Landscape architecture of trafficways Arquitectura paisajística de las vías de tráfico Aménagement paysager des voies de communication Landschaftsgestaltung für Verkehrswege Landskapsarkitektur for trafikkårer

16. Language-independent representation (2) 713 Αρχιτεκτονική τοπίου για αρτηρίες μεταφορών Ландшафтная архитектура транспортных путей אדריכלות נוף של דרכי תחבורה ﻕ ﻟﻠﻄﺮ ﺍﻠﻄﺒﻴﻌﻴﺔ ﺍﻠﻧﺎﻇﺮ ﺗﺼﻤﻴﻢ

17. Potential for customization (1) Choice of level of specificity Shelf arrangement Full vs. abridged edition Local practice Search Truncated search plus wildcard operator

18. Potential for customization (2) Search by subject component, using 085 - Synthesized Classification Number Components (MARC bibliographic format) 085 ## $b759 $a759.3 $c759.8 $z2 $r4 $t4 $u759.4 085 ## $b759.4 $z1 $t074 $u759.4074 Search on 75* and 2—44* for French painting and paintings

19. Potential for customization (3) Display using personal citation order Standard citation order in Table 1: place + time Europe, 19th century1—094034 Europe, 20th century1—09404 Asia, 19th century1—095034 Asia, 20th century1—09504 Africa, 19th century1—096034 Africa, 20th century1—09604

20. Potential for customization (4) Display using personal citation order Reverse citation order: time + place Europe, 19th century 1—094 + 034 Asia, 19th century 1—095 + 034 Africa, 19th century 1—096 + 034 Europe, 20th century 1—094 + 04 Asia, 20th century 1—095 + 04 Africa, 20th century 1—096 + 04

21. Benefits arising from the notation Large amount of categorized content Worldwide user community Language-independent representation Interoperable translations Mappings and crosswalks