This paper describes a computer program which produces English
discourse. The program is capable of describing in a sequence of
English sentences any game of noughts-&-crosses (tic-tac-toe), whether
given or actually played with the program. The object is to understand
something of what a speaker is doing when he speaks, and the program
therefore demonstrates the operation of rules for selecting information
into sentences, for connecting sentences into a discourse, and for
constructing clauses, groups, and words to convey the required
information with the maximum possible economy.
The program uses a systemic functional grammar to co-operate with
semantic procedures in producing English. The grammar generates only
a limited range of English, but one which is nonetheless sufficient to
illustrate the advantages both theoretical and practical of such a
grammar for a productive system.
Many other computer programs have accepted more or less natural
English input, usually in the form of questions requiring an answer,
but few have been designed to produce natural English, particularly
connected discourse. As a producing system the present model offers
a view of language use from a viewpoint slightly different from that
of its predecessors. However comprehension and production are
dependent on each other, so that study of one may be expected to illuminate the other