--2-- 
Harper's earlier sentence generation program differed 
from other versions in its use of data on lexical co- 
occurrence and word behavior, both obtained from machine 
analysis of written text. These data are incorporated 
with some modifications in a new program designed to pro- 
duce strings of sentences that possess the properties of 
coherence and development found in "real" discourse. (The 
actual goal is the production of isolated paragraphs, not 
an extended discourse.) In essence the program is designed 
(i) to generate an initial sentence; (ii) to "inspect" 
the result in order to determine strategies for producing 
the following sentence; (iii) to build a second sentence, 
.making use of one of these strategies, and employing, in 
addition, such criteria of cohesion as lexical class 
recurrence, substitution, anaphora, an4 synonymy; (iv) to 
continue the process for a prescribed number of sentences, 
observing both the general strategic principles and the 
lexical context. Analysis of the output ~ill lead to 
modification of the input materials, and the cycle will be 
repeated. 
This paper describes the implementations of these 
ideas, and discusses the theoretical implications of the 
paragraph generator. First we give a description of the 
language materials on which the generator operates. The 
next section deals with a program which converts the 
language data into tables with associative links to minimize