Elements of a plan-based theory of speech acts

The Sphinx once challenged a particularly tasty-looking student of language to solve the riddle: "How is saying'My toc is turning blue,' as a request to get off my toe, similar to slamming a door in someone's face?" The poor student stammered that in both cases, when the agents are trying to communicate something, they have analogous intentions. "Yes indeed" countered the Sphinx, "but what are those intentions?" Hearing no reply, the monster promptly devoured the poor student and sat back smugly to wait for the next oral exam. The research described herein was supported primarily by the National Research Council of Canada, and also by the National Institute of Education under Contract US-N1E-C-400-76-0116, the Department of Computer Science of the University of Tor3nto, and by a summer graduate student associateship (1975) to Cohen from the International Business Machines Corporation.