The present paper presents a philosophical approach to knowledge organization, proposing the pragmatic doctrine of CS Peirce as basic analytical framework for knowledge domains. The theoretical framework discussed is related to the qualitative branch of knowledge organization theory ie within scope of Hjørland’s domain analytical view (Hjørland and Albrechtsen 1995; Hjørland 2002; Hjørland 2004), and promote a general framework for analyzing domain knowledge and concepts. However, the concept of knowledge organization can be viewed in at least two perspectives, one that defines knowledge organization as an activity performed by a human actor eg an information specialist, and secondly a view that has the perspective of the inherent self-organizing structure of a knowledge domain the latter being investigated in the paper.