Citation Indexes for Science: A New Dimension in Documentation through Association of Ideas #
In the course of my reading I did find a few references to this device, one in a book, and several others in periodical articles, one of which was a Ger¬man article on the mechanisation of philological analyses and concordance building. The latter article (If) did not discuss my own special interest in copy¬ing devices, but is did show the similarity between the author's and my own think¬ing from the point of view of letter-rec¬ognition devices, which is what the RCA device attempts to be. In other words, both of as were interested in this device as a letter-recognition device for the analysis of text.
In another instance the RCA article was unexpectedly cited in the joumal Electronic Engineering in an article on information theory (12) that I was reading because of an entirely different in¬terest. No subject indexer could have anticipated this crossbreeding of interests. Perhaps there are many other articles and books unknown to me that have made similar references to this device. How can they be located when the main subject matter of the article is, on the surface, so unrelated in nature?
One might say that it would be possible to index articles more thoroughly to achieve the same results. For example, the article on information theory, if thoroughly indexed, might have included an entry under reading devices for the blind. Yet if this were done, our periodical indexing services would clearly become hopelessly overloaded with material that is not necessary to lead us to the micro unit—the entire article or one of its major sections. Although it might be said that no scientist interested in the greater comprehensiveness to be found in a citation index would object to having such a great mass of references in a subject index, this is impracticable. It would require an army of indexers to read the articles and identify the exact subject matter of every paragraph or sentence. Yet this would be necessary. To illustrate, it is only in the very last paragraph of the article on information theory that one would find a reference to reading devices for the blind.
Were an army of indexers available, it is still doubtful that the proper subject indexing could be made. Over the years changes in terminology take place, that vitiate the usefulness of a standard subject index. To a certain extent, this is overcome through the citation approach, for the author who has made reference to a paper 40 or 50 years old has interpreted the terminology for us. By using authors' references in compiling the citation index, we are in reality utilizing an army of indexers, for every time an author makes a reference he is in effect indexing that work from his point of view. This is especially true of review articles where each statement, with the following reference, resembles an index entry, superimposed upon which is the function of critical appraisal and interpretation. To the indexer this has its advantages as well as its disadvantages (13).