Abstract

The modern (Russellian) theory of definition conceives definitions as abbreviations, so that the question of adequateness (let alone of truth-value) of definitions becomes meaningless. In this paper we show that beside Russellian conception of definitions understood as abbreviations, there is an Aristotelian conception, which exploits the notion of essence and that this conception can be rehabilitated from the standpoint of the modern logic (in particular by means of Pavel Tichý’s Transparent Intensional Logic). Also Carnap’s ‘explication’ indicates that what we feel to be a definition is frequently distinct from a Russellian definition.