Q. How are the terms used in LC (Library of Congress) subject headings determined and why works on the same subject are placed throughout the collection?
Subject Heading Basics
In the construction of subject headings, the Library of Congress takes into consideration user needs, current usage, and "literary warrant." In an attempt to meet user needs, the Library of Congress makes the following assumptions in the formulation of subject headings: that subject headings allow the patron to locate an item of which the subject is known and that subject headings allow the user to find what the library has on a particular subject. To ascertain the current usage aspect of subject heading construction, reference works such as general indexes and thesauri are consulted, as well as current literature in the specific field. The concept "literary warrant" refers to the literature on which the subject headings are based. In other words, subject terms used in works taken from the library's own collection are in turn, used in the formulation of subject headings.
Why Works on the Same Subject are Placed Throughout the Collection
Within classification systems, such as the Library of Congress, the overriding principle is to organize information by academic discipline (fields of knowledge) rather than by subject. As a result, the same topic could conceivably be located in many different areas of the collection. For example, a book on Texas could be classed in law, medicine, or history. How a topic is viewed within a discipline then, as well as the individual author's approach or perspective, can determine where a book is located (classed) within the library collection.