ABSTRACT
According to a traditional and pervasive view in semantics, general terms such as ‘gold’, ‘tiger’, ‘philosopher’, ‘computer’, or ‘Mary’s favourite colour’ designate universals: abstract entities such as substance and artifact kinds, colours, and species. This view (from now on The View) may be metaphysically unpalatable, especially for those of a nominalist persuasion, since it goes hand in hand with what may be seen as an overpopulated ontology. However, The View has, as of late, come into disrepute, not for metaphysical reasons, but for purely semantic reasons: it is argued that The View does not allow for a signifi cant characterization of the notion of rigidity for general terms. The View appears to suggest a very natural extension of the notion of rigidity that Kripke defi ned only for singular terms. Singular terms are rigid just in case they designate the same individual with respect to all indices of evaluation, or possible worlds. Since The View treats general terms as designators, it is natural to defi ne the rigidity of general terms in a similar way: a general term is rigid just in case it designates the same universal with respect to all indices of evaluation. In principle this characterization seems to accord with our initial judgments about rigidity: ‘blue’ is rigid because it designates the same colour with respect to all possible worlds, whereas ‘Mary’s favourite colour’ is surely not rigid: had Mary’s taste been different, ‘Mary’s favourite colour’ would have designated a different colour.
