Definitions: Does disjunction mean dysfunction?

Abstract

Our concern in this paper is with definitions that are not conjunctive. In particular, our concern is with definitions of things of a kind K which allege that there is a bunch of conditions, each of which is sufficient, but not necessary, for bestowing K-hood. Definitions of this kind, call them “disjunctive,” are often proposed for kinds of things that interest us, but they usually draw fairly muted applause. Many treat them as provisional, to be endured, rather than celebrated. Surely, it is thought, they do not provide all one might want from a definition. Because of water, art and other cases which apparently problematise the boundary between practice-mandated and theoretically-posited kinds, there will doubtless continue to be disagreements about the credentials of disjunctive definitions. Even so, we think we have gone some way towards offering a reasonable justification for the on-going debates and some apparatus for formulating the issues.