Implementing a semantic interpreter using conceptual graphs
by J. F. Sowa, E. C. Way
A parser applies grammar rules to generate a parse tree that shows the syntactic structure of a sentence. This paper describes a semantic interpreter that starts with a parse tree and generates conceptual graphs that represent the meaning of the sentence. To generate conceptual graphs, the interpreter joins canonical graphs associated with each word of input. The result is a larger graph that represents the entire sentence. During the interpretation, the parse tree serves as a guide to show how the graphs are joined. Both the front-end parser and the back-end semantic interpreter are written in the Programming Language for Natural Language Processing (PLNLP).