Categories don’t take precedence

The morphological component of an LRFG grammar is responsible for selecting the word forms (Vocabulary Items, or VIs) which express a given sentence. VIs may realize only a subset of the information in a sentence, but MostInformative_f (MIf ) and MostInformative_c (MIc ), which evaluate the f- and c-structure information a VI realizes (respectively), ensure that sentences are expressed using the fewest VIs that realize the most information possible. Welsh has positive, negative and neutral forms of the copula in the present and imperfect paradigms which compete to realize copula-containing structures. The Welsh data regarding which form is selected in different contexts is used to show two important conclusions: (1) that constraining equations have a different status to defining equations in VIs, the former not contributing to the evaluation of MIf , and (2) that MIf outranks MIc when the two metrics return different VIs according to their evaluation.