In the paper, Prior's well-known 'tonk' argument is examined and taken as a basis for general considerations regarding the logical status of implicit ('inferential') definition, and the semantical status of the 'tonk'-like expressions. Further, the whiff of logical vanity attendant upon Priorś conclusions is dispelled by employing a new theory of concept. In particular, the authors argue that: a) Prior's 'tonk' argument discredits neither the concept of analytical validity nor the role of implicit definition. The arguments underlying the authors' view draw from both syntactical and semantical considerations of the alleged 'tonk' connective. b) Decisive criticism of the very concept of implicit definition of logical connectives can be, anstead, based on Tichý's view of formal axiomatics as a case of 'the Fallacy of Subject Matter'. c) The semantical analysis of the so-called 'strictly empty' concepts, as introduced by Materna in his theory of concept, renders a viable account of the mysteries and confusions surrounding Prior's witty and inspiring 'tonk' example.
*Príspevok je chránený zákonom o autorskom práve a právach súvisiacich s autorským právom (autorský zákon).