DL* Slowly Sinks ... (Conclusions )

Abstract

The implementation of a sentential search directed language modeled on the first order predicate calculus must, if it is to preserve the common meaning of the quantifiers and connectives of the calculus, either restrict its admissable syntax considerably (to something like the separable statements of chapter two, containing no disjunctions in a search determining section of a statement), have no sophisticated search limiting mechanism, answering questions by a search (probably exhaustive) over a large segment of the data base, or internally contain one of the more sophisticated features of modern programming languages, the ability to suspend and resume processes, If disjunctions are permitted in search determining parts of statements, then a related feature, automatic backtracking, must also be added, and in addition, some means to terminate the backtracking when it is no longer desired. This means may be either manual (as in DL*.) , or extremely sophisticated automatic (further research is suagested). Thus, the originally stated goal of this research , namely, the creation and Implementation of an efficient search directed question answering system, became essentially the task of creating and implementing a moderately sophisticated programming language. Many of the originally anticipated difficulties, for instance, when to terminate a quantified search, and in general , when to advance an inner quantified search, were subsumed by the problem of determining the process structure of a Statement, and the resulting run time control graph of the statement.