In this chapter we set out the broad descriptive generalizations which emerge from investigations of argument realization and its lexical semantic underpinnings, as well as the methodological issues which a comprehensive theory of argument realization must address. These constitute the major challenges for a theory of lexical semantic representation and a theory of argument realization that dovetails with it.

Taking lexical semantic representations seriously

Since the 1980s, many theories of grammar have been built on the assumption that the syntactic realization of arguments – their category type and their grammatical function – is largely predictable from the meaning of their verbs. Such theories take many facets of the syntactic structure of a sentence to be projections of the lexical properties of its predicator – its verb or argument-taking lexical item; see Wasow (1985) for discussion. To ensure this, these theories incorporate conditions requiring that the arguments of the verb are appropriately represented in the syntactic representation of its clause. Such principles include the Principles and Parameters framework's Projection Principle (Chomsky 1981: 29, 38), Lexical-Functional Grammar's Completeness and Coherence Conditions (Kaplan and Bresnan 1982: 211–12), and Role and Reference Grammar's (RRG's) Completeness Constraint (Foley and Van Valin 1984: 183; Van Valin 1993b: 74–75; Van Valin and LaPolla 1997: 325–26). The successful implementation of the program of deriving the syntactic properties of verbs from facets of their meaning depends on the existence of both an articulated theory of the lexical semantic representation of verbs and a theory of the mapping between this representation and the relevant syntactic representation.