Compositional Semantics and Semantic Parsing
Building the meaning of a sentence from its parts and mapping natural language to formal meaning representations such as logical forms and executable queries.
Definition
Compositional semantics computes the meaning of a complex expression from the meanings of its constituents and their mode of combination; semantic parsing maps natural language to a formal meaning representation.
Scope
Covers the construction of sentence-level meaning: the principle of compositionality, logical-form representations, the syntax–semantics interface, and semantic parsing that maps utterances to formal representations usable for inference or database queries. It includes both formal and learned approaches. Word-level meaning is covered in lexical semantics and discourse-level meaning in a sibling topic.
Core questions
- How is sentence meaning assembled compositionally from word meanings and structure?
- How are quantifiers, scope, and negation represented in logical form?
- How can semantic parsers be learned from data?
- How are meaning representations used for inference and querying?
Key concepts
- compositionality
- logical form
- lambda calculus
- quantifier scope
- syntax-semantics interface
- semantic parsing
- meaning representation
- inference
Key theories
- Montague grammar
- Montague's program of treating natural language with the rigor of formal logic, pairing syntactic rules with semantic operations to compute truth-conditional meaning.
- Learned semantic parsing
- Inducing a parser that maps sentences to logical forms from annotated examples, using probabilistic categorial grammars and structured prediction.
History
Montague's 1970s work showed natural language could be given a precise model-theoretic semantics, inspiring computational implementations surveyed by Blackburn and Bos. From the mid-2000s, semantic parsing turned to machine learning, with Zettlemoyer and Collins learning logical-form mappings from data, a line that continues into neural semantic parsing.
Debates
- Hand-built versus learned meaning representations
- Whether formal logical forms should be designed by hand or induced from data, and how much explicit logical structure neural systems still need for reliable inference.
Key figures
- Richard Montague
- Patrick Blackburn
- Johan Bos
- Luke Zettlemoyer
Related topics
Seminal works
- montague1973
- blackburn2005
- zettlemoyer2005
Frequently asked questions
- What is a logical form?
- A logical form is a formal, unambiguous representation of a sentence's meaning, often in a logic such as the lambda calculus, that a computer can use to reason or to query a database.