On the logical necessity and priority of a monothetic conception of class, and on the consequent inadequacy of polythetic accounts of category and categorization

Abstract

For three decades now the ideology of polytypy has held sway in the fields of classification and cognitive science, dictating the direction of research almost to the exclusion — and hence to the detriment — of other lines of thinking. This paper questions that ideology, arguing that monotypy has logical priority over polytypy, and that consequently any polytypics! conception of category and categorization is misguided and in need of re-interpretation. In the development of the argument, historical background to the distinction between monotypy and polytypy is reviewed, a critique of polytypy is presented, its range of application is made explicit by reference to class-of-objects words, and two meanings of “classify” are distinguished to define the agenda of classification.