Languages for intelligent specification systems

By writing specifications as theories of a logic system, the authors use proof theory to ensure that (a) the consequences of theory are properties of the object being specified, and (b) any known property of the object can be proven as a theorem of the theory. They define an extension of first-order logic that deals with events with actions. The resulting logic is a special type of modal logic with a notation similar to that of Hoare-style logics. Specifications are theories of this logic.<
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