Fun with Google Ngram Viewer, pt. 2.

The chart below delineates references to five library classification schemes (Dewey Decimal Classification, Library of Congress Classification, Universal Decimal Classification, Colon classification, and Bliss Bibliographic Classification) in books published between 1950 and 2008. As the search terms are relatively uncommon in the Google Books corpus, I’ve smoothed the data by using 5-year rolling averages. The terms are case-insensitive.

ngram (major classification schemes)

Classifiers won’t be surprised to see DDC and LCC dominating today. Published interest in other schemes has almost been extinguished in the English-speaking world. But the early data hints at a radically different perspective on library classification two generations ago, when faceted schemes looked like realistic alternatives to the two (mainly) enumerative schemes now ascendant.

In the late 1950s, there were more printed references to UDC than to any other scheme; the same was true of Colon classification in the early to mid 1960s. Interest in BC peaked in the 1980s. No other classification scheme generates statistically meaningful data.

The fall-off in discussion of individual schemes has not been as precipitous as that for library classification generally. Updates to DDC and LCC continue to be published regularly, maintaining a background hum of references.


Phyllis Allen Richmond (1921-1997) was one of the greatest 20th-century classificationists, and I return to her writings whenever I despair of the obscurity and narrow focus general among many modern writers in the field. I share her skepticism of the library classification schemes that attempt to make the world fit an inflexible model, however granular or faceted that model might be.

Her essay, ‘Some aspects of basic research in classification’ published in Library Resources and Technical Services in the Spring of 1960, takes some well-aimed potshots at the cult of Ranganathian subject analysis, then prevalent. Here’s a brief extract:

‘The Dewey, Universal Decimal and Bliss classifications are made primarily by logical division, which is mirrored to some extent in their notations. The Library of Congress classification, in contrast, is definitely non-logical and the notation is largely ordinal. This classification functions as well, if not better, than the others. A non-logical classification has the great advantage of flexibility, since one may add to it rather freely without upsetting the whole pattern. The fact that the Library of Congress classification is displayed in an almost random fashion, after some initial form divisions in each main class, does not seem to be a disadvantage in its operation. In a non-conventional classification, the elements of each category may be expressed either in a logical or a non-logical manner. The advantage of variability, rather than the display of relationships, is the chief motivation for choosing a non-logical arrangement.’