Thus, CHAT, and all other hypertext systems, are specialized examples of finite automata and are, in principle, capable of emulating any digital computer. The implication of all of this is that, in principle, CHAT, by encoding behaviours in a finite automaton, should not be limited in what it can do. In practice, finite automata are usually very clumsy ways to perform complex operations. However, CHAT systems are usually surprisingly simple, so that a finite automaton does provide a practical basic model. Of course, to make CHAT truly practical, it was necessary to develop a search algorithm which augments the basic operations of a finite automaton in some interesting directions.
Some linguists use augmented transition networks to model natural grammars.
Thus, CHAT may, in fact, be capable of modeling true linguistic grammars in principle. The problem is that long before that point, the CHAT network would become unbelievable large and complex. If I were working in computational linguistics, rather than computational behaviourism, I would quickly abandon CHAT in favor of the more elegant models of the linguists. TIPS, the other program that I have developed is similar to CHAT in its basic philosophy, but uses much more powerful information structures in order to perform much more powerful behavioural operations.