As it is known, the ISIS bibliography was first indexed according to a classification system originally developed by George Sarton. Sarton’ system was derived from his notions of time period and scientific disciplines. Following him, Magda Whitrow was invited to work with the cumulative bibliography. She had then created an indexing system- thought to supplement his initial classification- which was a facet system of classifying entries based on the facets of a subject. Steve Weldon had developed it into seven facets, and transformed in a way to improve the system. As Withtrow reminds us, Sarton’s classification had already an implicit facet classification in it. The faceted classification theory- as developed by S.R.Ranganathan in his Colon Classification, have been extensively used for research focused in knowledge classification and information systems. Alongside his philosophy, facet theory was also developed by the Classification Research Group in UK, which has been providing guidelines in dealing with documentation for the construction of facet-based systems.

In CESIMA, a pilot project has been developed to discuss how facet theory can be applied in creating a new system of classification for the History of Science. Special attention in this paper will be given to classifying documents of the Renaissance, more specifically documents where Musical knowledge, Mathematics and Natural Philosophy coexist. The difficulties found within the classification of such documents concern misleading classification of content subject, misleading terminology in choosing descriptors as misleading abstracts for catalogation. While this is a working progress project, yet the difficulties found in classifying these documents are outspoken. The difficulties with the classification of these type of documents can be also found while searching for similar content documents either in libraries, or in the internet databases. This selection of documents has proved to be a particular good sample for the development of the tools and philosophies of our project. This paper aims at providing some of the outlines and the initial problems found in applying and developing CESIMA’s classification in such specific documents in the History of Science. (Funded by FAPESP 09/52252-8).