INTRODUCTION

The integration of syntactic and semantic processing has prompted a number of different architectures for natural language systems, such as rule-by-rule interpretation [221], semantic grammars [22] and cascaded ATNs [253]. The relationship between syntax and semantics has also been of central concern in theoretical linguistics, particularly following Richard Montague's work. Also, with the recent rapprochement between theoretical and computational linguistics, Montague's interpretation scheme has made its way into natural language systems. Variations on Montague's interpretation scheme have been adopted and implemented in several syntactic theories with a significant following in computational linguistic circles. The first steps in this direction were taken by Hobbs and Rosenschein [89]. A parser for LFG was augmented with a Montagovian semantics by Halvorsen [76]. GPSG has been similarly augmented by Gawron et al. [65], and Schubert and Pelletier [206] followed with a compositional interpretation scheme using a first order logic rather than Montague's computationally intractable higher-order intensional logic.

In parallel with these developments in the syntax/semantics interface, unification-based mechanisms for linguistic description had significant impact both on syntactic theory and syntactic description. But the Montagovian view of compositionality in semantics and the architectures for configuring the syntax/semantics interface were slower to achieve a similar revaluation in view of unification and the new possibilities for composition which it brought.