In 1933, an Indian mathematician and librarian, S R Ranganatllan, introduced a new form of knowledge organization system, though still discipline-based and called it a faceted system, as it provides in faceted (category-derived) order the "building blocks" for compositional expressions of subjects in sentence form, As he used the colon to symbolize the connection between the subject and the predicate of his classificatory sentences he called his system Colon Classification. When, after World War II, his system and methodology became known in the West, many faceted classification systems were elaborated in many fields of knowledge and even alphabetical descriptor systems, as [eg] thesauri, were developed in faceted structure. As mentioned above, facets are related to categories and knowledge units/concepts organized in facets have the advantage to be accessible in mutually exclusive classes allowing any kind of concept combination according to the requirements of a given case.
It has been defined (FID/CR 1964) that "by classification is meant any method creating relations, generic or other, between individual semantic units, regardless of the degree in hierarchy contained in the systems and of whether those systems would be applied in connection with traditional or more or less mechanized methods of document searching". And indeed, the human capability to make judgements, [ie] to formulate sentences in which a subject is related to a predicate, is an innate one, given to every sane human being together with his reason and his free will as well as his capability to distinguish between truth and untruth. When human beings are making judgments consciously or not - they are classing, as the predicates of their judgments relate to a kind of reality which can also be expressed in the form of a concept or a concept class in a classification system.
Thus, whoever wants to organize knowledge needs to create a conceptual representation of the objects of his knowledge and of the activities connected with these objects as well as the properties, conditions, and other relationships occurring with them. In such an analytical way the building blocks for knowledge units/concepts are organized; they will then serve to create in an almost self-organizing way the necessary order (a) of the objects of concern by bringing together what belongs together, and (b) in the likeness of the functioning of objects in their activities and in interaction with their properties, purposes and their proper environment.