Keyword Search vs Subject Search by LCSH

In respond to the thinking of “Google makes books easily accessible”, Dr. Thomas Mann, in his paper “What is Distinctive about the Library of Congress in Both its Collections and its Means of Access to Them…” (2009) compared the keyword search and subject search based on LCSH (p.11-14):

“Tens of thousands of examples are possible here; for the present we will have to let one suffice: the subject cataloging access to books on “Afghanistan” that is infinitely more efficient in providing an overview of the whole scope of our relevant collections than could be provided by either Google or Amazon search mechanisms. And I need not emphasize how important it is to our national interest that Congress, and scholars generally, have access to as much knowledge on this subject as we can possibly provide.

A researcher using LC’s online catalog can easily call up a browse-display such as thefollowing:

Afghanistan—Constitutional history
Afghanistan—Defenses—History—20th Century—Sources
Afghanistan—Description and travel
Afghanistan—Economic conditions
Afghanistan—Economic Policy
Afghanistan—Emigration and immigration

……. <snipped>

Such “road map” arrays in our OPAC enable scholars who are entering a new subject area to recognize what they cannot specify in advance. They enable scholars to see “the shape of the elephant” of the book literature on their topic early in their research.

Neither Google nor Amazon makes such systematic overviews of subjects accessible at all, let alone “easily accessible.”

Subject cataloging in our OPAC accomplishes the goal of extending the scope of scholars’ inquiries by showing them more of the full range of what is available than they know how to ask for before they are exposed to it. LCSH cataloging enables them both to recognize a much broader range of topical options within their subjects that would not occur to them otherwise; and it also enables them to pick those aspects of interest in a way that separates them from other aspects that would only be in the way, as clutter, without this roster of conceptual distinctions to choose from.

…… <snipped>

… LC now has a new way (the Subject Keyword option in our OPAC’s Basic Search menu) to bring up, systematically, a browse-menu of all other headings in which Afghanistan is itself a subdivision of another topic, for example:

Abandoned children—Afghanistan
Administrative law—Afghanistan


Buddhist antiquities—Afghanistan
Cabinet officers—Afghanistan—Biography


Muslim women—Afghanistan
Muslim women—Education—Afghanistan—Bibliography
Rural women—Afghanistan—Social conditions
Sex discrimination against women—Afghanistan
Single women—Legal status, laws, etc.–Afghanistan
Women—Afghanistan—Social conditions

…. <snipped>”