1. Any classification system is arbitrary.

Classification numbers are arbitrary, that is they have no essential meaning or value other than that which we give them. In the same way, a dollar bill only has value because we all agree that it does — it is really just a piece of paper. Similarly, a classification scheme is just an agreed-upon system for organizing library materials in a particular library.

Along these lines, it is worth noting that the very same book will have different call numbers depending on what classification system is in use. Sometimes the call numbers of the same book classified with the same system will even vary from library to library!

For example:

The Ethics of Authenticity, by Charles Taylor, 1992.

 
Beyond the Whiteness of Whiteness, by Jane Lazarre, 1996.

     
The Monthly Labor Review

 

2. Any classification system is imperfect.

“There is a constant tension in bibliographic classification between the one-dimensional linear order that is necessary for useful shelf arrangement and the more complex, multidimensional set of relationships that exist between concepts. Thus a truly effective classification system may need to reveal links and relationships which are impossible to show when books are placed on shelves.”
-John Feather and Paul Sturges, eds. International Encyclopedia of Information and Library Science. New York: Routledge, 1997. “Classification,” pp. 57-58.

“Books are the written expression of man’s ideas and these ideas are complicated. Several subjects may be discussed in one book, one subject may be discussed from several different aspects. Both factors may appear together. The way in which books on the same subject are presented to the reader may differ, or the standard of knowledge required may vary, e.g. nuclear physics. Readers require books for different purposes and an arrangement that satisfies one may not satisfy another.”
-Thomas Landau, ed. Encyclopedia of Librarianship. 3rd rev. ed. New York: Hafner Publishing Co., 1966. “Classification,” p. 103.

With these comments in mind, it is helpful to remember that the primary use of the LC Classification system is as a location tool – a way to arrange books on the shelf. Call numbers are essentially a “street address” for a book. They tell us where it “lives” on the shelves of the library.

As have seen, call numbers are closely related to the subject of the book. But they are usually not the best way to search for books by subject. The primary way of searching for books by subject is to use the Library of Congress Subject Headings


3. Any classification system embodies the values and assumptions of its creators

Though at first appearing objective and scientific, the LC Classification System, just like any system, is not value neutral. A closer look at the LC System reveals the values and assumptions of its creator and the society of which he is a product.