Foundational Work in Glue Semantics

An LFG-based deductive approach to the syntax-semantics interface

This page focuses on work up to 2001.

Foundational Work in Glue Semantics


Formalisms for assembling a meaning for a natural language utterance have traditionally been closely tied to syntactic structure. For example, the Montague approach of function application presumes a deeply nested binary tree structure to guide the applications. Categorial grammar approaches combine both syntax and semantics in the same formalism, leading to formidable complications. We believe that the functional structure of Lexical-Functional Grammar is better suited to provide the syntactic information necessary for constraining derivations of meaning in a cross-linguistically uniform format. It has been difficult, however, to reconcile this approach with the combination of meanings by function composition.

[proof of `Bill left'] In contrast to compositional approaches, we have been working on a deductive approach to assembling meanings, based on reasoning with constraints, which meshes well with the unordered nature of information in the functional structure. We found that simple logical implication was very good at modeling the assembly of meanings in a sentence, and could connect up with the functional structure easily.

Schematically, if we have the sentence "Bill left", we can take the semantic contributions to depend on syntactic information in the following way:

bill: The subject means Bill
left: If the subject means X, then the sentence means left(X).

from which we can infer that the sentence means left(Bill).

Much more complex constructions can be handled straightforwardly. Our use of linear logic as a `glue' for assembling meanings also allows for a coherent treatment of modification, and the linear logic version of implication is just what is needed to capture the property of natural language that each part of a sentence contributes exactly once (usually) to the final meaning.


Natural Language Theory and Technology
Palo Alto Research Center
3333 Coyote Hill Rd.
Palo Alto, CA 94304 USA

This page updated March 2006.