Thursday, February 26, 2009

the Dewey Decimal System and the Library of Congress Classification

i became interested in library book classification systems when i was a student at Yale and observed there the transition the library went through from its own classification system to the Library of Congress system. with several million books there it was of course a major and lengthy project. i was mystified by the decision to change. from the appearance of the two systems there didn't seem to me to be any advantage of the LC system over the Yale.

finally today i did a little work of my own and found a website about the history of the Dewey system that i knew was widespread in the united states and was the system used by my hometown public library. here is that website.

i also went to wikipedia for their entry on the Dewey Decimal System and there the differences between library of congress and dewey decimal are discussed.

at wikipedia it is observed that dewey decimal is a top-down system, having been created by one man and his determinations extend downward hierarchically to all branches of knowledge. this the advantage of simplicity.

it is also observed that the library of congress system is filled out by the work of experts each in his own field so that recent developments can always be incorporated into the system. this has an obvious advantage but it has the disadvantage of tending to inconsistency since the various experts are not bound to create a consistent system. the dewey system does not have this disadvantage but it is weak because it does not have the advantage the library of congress system has of being easily updatable.

there is also the consideration that dewey has gone to great lengths to make itself available all over the world whereas the library of congress system is primarly and characteristically american. i had thought when yale made the change that the whole world was switching to LC and that this was the reason for the change. not so, apparently. though yale's system is defunct, dewey is still widely used around the world and in the u.s. too.

technically this post is a departure from the intent of this blog to do all the research in the stacks here rather than on the internet. but that intent is not meant to be a burden, only a special pleasure of mine, and it seemed appropriate to accent it with a little net work. the present post serves better understanding of library book shelving, in any case. this library where i frequent, the chicago public library main branch, the harold washington library center, uses the LC system.