Aspect or discipline versus

entity or phenomena or "one place" classification

Mills & Broughton (1977, p. 37) made a very clear argumentation for the use of disciplines as the basic organizing principle in the introduction to the Bliss 2 system. They wrote:


           "5.55       Disciplines and phenomena      

           5.551         It should be clear from the last section (5.542) that although the disciplines reflect discrete systems of knowledge they yet share to some degree the same phenomena studied. The implication of this for a general classification is that the basic organization of information will subordinate material on a given phenomenon to the discipline or subdiscipline from whose viewpoint it is being regarded. So documents on the subject of the phenomenon "Color" for example, will not be kept together insofar as they will be assigned to the different disciplines (Physics, Art, etc.) their treatment reflects.                  

           5.552           However, it should be recognized that there is, theoretically, a quite different way of organizing a general classification. This would be to make the first division of the field of knowledge into phenomena (from subatomic particles to planetary bodies and stars, from single cells to particular organisms and particular societies, and so on) and to subordinate to each phenomenon the disciplinary aspects from which it may be treated; e.g. Color—in Optics, in biology, in Art, etc.; or, Food—in Agriculture, in Nutrition, in Cookery, in Economic resour­ces, etc.; or, Water—in Chemistry, in Geology, in Biology, in Engineering, in Transport, etc.   

           5.553           Such an arrangement would run counter to the way we usually study things and the way most information is marketed, which reflects the division of labor by discipline. There are relative few persons, if any, specializing in a given phenomena from all its aspects. Indeed, such a specialized study would require a training, which is at present hard to envisage. 

           5.554           Nevertheless, a growing number of documents do reflect a multi-disciplinary approach, although authorship of such works is usually, and not surprisingly, also multiple, as in the case of symposia. Such material poses a special problem for the older general classifications, which are sometimes called "aspect" classifications in that their basis of arrangement is by aspect or "discipline", not by phenomena. This does not, however, invalidate the general correctness of the decision they all reflect, which is to treat classification by discipline as being on the whole more helpful to users. It may be noted that the factual literature for children has always shown a strong tendency to con­centrate on phenomena rather than discipline—e.g., "the big book of trains" which considers most aspects of the railway system". (Mills & Broughton, 1977, p. 37).


In a similar way The Dewey Decimal Classification (DDC) states that


 “a work on water may be classed with many disciplines, such as metaphysics, religion, economics, commerce, physics, chemistry, geology, oceanography, meteorology, and history. No other feature of the DDC is more basic than this: that it scatters subjects by discipline” (M. Dewey, 1979, p. xxxi; emphasis added).


Organization of knowledge "from subatomic particles to planetary bodies and stars, from single cells to particular organisms and particular societies, and so on" reflects in our view a systems theoretical and rationalist perception (or ideal) of knowledge (cf., Ryan & Bohman, 1998; Markie, 1998), whereas an organization reflection disciplinary organization and thus human interests reflects historicist and pragmatic views on knowledge. In our view, the illumination of strong and weak points in the two alternative solutions are closely related to strong and weak parts in respec­tively rationa­listic and  historicist/pragmatic philosophy. Further argumentation for the historical and pragmatic view are given in Hjørland (1997).


"Knowledge classification can be, and often is, TAXONOMIC (sometimes called 'entity classification') like the classification of zoology, classification of plants, or classification of chemical elements (which means that they are going to list one concept in one place only in the classification structure).

    Bibliographic classifications i.e. those one has to use to describe real documents ARE NOT and CAN NOT be taxonomic. They are by all means ASPECT or disciplinary classifications. This means that they will list one concept in all disciplines and fields where that concept might be studied: e.g. 'water' will have to appear under chemistry, physics, in geology, medicine, sport etc.

    This is of critical importance for information retrieval as aspect classification helps to establish the context in which one concept or phenomenon might be studied within the document." (Slavic, 2000).




J. D. Brown advocated "One-place" classification. “Concrete” subjects should have only one place, qualified by “standpoints” (cf., Beghtol, 2004a+b).  






Ahlers Møller, B. (1981). Subject analysis in the library: A comparative study. International Classification, 8(1), 23-27.


Beghtol, C. (2004a). Exploring new approaches to the organization of knowledge: The subject classification of James Duff Brown. Library Trends, 52(4), 702-718.


Beghtol, C. (2004b). The subject classification of James Duff Brown (1862-1914). ASIST SIG/CR: Providence, RI.


Dewey, M. (1979). Dewey Decimal Classification and relative index. (19th ed., Vol. 1). Albany, NJ: Forest Press.


Hjørland, B. (1997): Information Seeking and Subject­ Representation. An Activity-theoretical approach to Information Science. West­port & London: Greenwood Press.


Markie, P. J. (1998). Rationalism. IN: Routledge Encyclopedia of Philo­sophy, Version 1.0, London: Routledge, Vol. 8, pp. 75-80


Mills, J. & Broughton, V. (1977). Bliss Bibliographic Classification. Second Edition. Introduction and Auxiliary Schedules. London: Butterworths.


Ryan, A. & Bohman, J. (1998). Systems theory in social science. IN: Routledge Encyclopedia of Philosophy, Version 1.0, London: Routledge 

Slavic, A. (2000). A Definition of Thesauri and Classification as Indexing Tools

(Visited 20-12-2005).




See also: Bendtsen; Disciplinarity and interdisciplinarity (Epistemological lifeboat); Phenomenon class




Birger Hjørland

Last edited: 30-06-2006