KI 1994: KI-94: Advances in Artificial Intelligence pp 331-342 | Cite as
Unification in a sorted λ-calculus with term declarations and function sorts
Abstract
The introduction of sorts to first-order automated deduction has brought greater conciseness of representation and a considerable gain in efficiency by reducing search spaces. This suggests that sort information can be employed in higher-order theorem proving with similar results. This paper develops a sorted λ-calculus suitable for automatic theorem proving applications. It extends the simply typed λ-calculus by a higher-order sort concept that includes term declarations and functional base sorts. The term declaration mechanism studied here is powerful enough to subsume subsorting as a derived notion and therefore gives a justification for the special form of subsort inference. We present a set of transformations for sorted (pre-) unification and prove the nondeterministic completeness of the algorithm induced by these transformations.
Keywords
Inference System Partial Function Deduction System Structure Theorem Valid SignaturePreview
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