Core classification theory: a reply to Szostak

Purpose - The purpose of this paper is to provide an answer to a critique put forward by Szostak against a paper written by the present author. Design/methodology/approach - The paper is based on a literature-based conceptual analysis based on Hjorland and Nissen Pedersen and Szostak. The main points in a core theory of classification are outlined and Szostak's criticism is examined and answered. Findings - The paper demonstrates theoretical differences between the views adduced by Hjorland and Nissen Pedersen on the one side and by Szostak on the other. Practical implications - Theoretical clarification is important for the future development of the field. Originality/value - The paper should be seen as one among others developing an argument for a theoretical foundation of classification informed by the theory of knowledge.