QA4: A Procedural Calculus for Intuitive Reasoning.
J. F. Rulifson, Jan Antonius Cornelius Derksen, Richard J. Waldinger · Defense Technical Information Center (DTIC) · 1972
This report presents a language, called QA4, designed to facilitate the construction of problem-solving systems used for robot planning, theorem proving, and automatic program synthesis and verification. QA4 integrates an omega-order logic language with canonical composition, associative retrieval, and pattern matching of expressions; process structure programming; goal-directed searching; and demons. Thus it provides many useful programming aids. More importantly, however, it provides a semantic framework for common sense reasoning about these problem domains. The interpreter for the language is extraordinarily general, and is therefore an adaptable tool for developing the specialized techniques of intuitive, symbolic reasoning used by the intelligent systems.