Computability logic (CL) (see http://www.cis.upenn.edu/~giorgi/cl.html ) is a research program for redeveloping logic as a formal theory of computability, as opposed to the formal theory of truth which it has more traditionally been. Formulas in CL stand for interactive computational problems, seen as games between a machine and its environment; logical operators represent operations on such entities; and "truth" is understood as existence of an effective solution. The formalism of CL is open-ended, and may undergo series of extensions as the studies of the subject advance. So far three -- parallel, sequential and choice -- sorts of conjunction and disjunction have been studied. The present paper adds one more natural kind to this collection, termed toggling. The toggling operations can be characterized as lenient versions of choice operations where choices are retractable, being allowed to be reconsidered any finite number of times. This way, they model trial-and-error style decision steps in interactive computation. The main technical result of this paper is constructing a sound and complete axiomatization for the propositional fragment of computability logic whose vocabulary, together with negation, includes all four -- parallel, toggling, sequential and choice -- kinds of conjunction and disjunction. Along with toggling conjunction and disjunction, the paper also introduces the toggling versions of quantifiers and recurrence operations.
与经典逻辑是真的形式理论一样,最近提出的可计算性逻辑也是可计算性的形式理论。它将(交互式)计算问题理解为机器与环境的博弈,将其可计算性理解为总是赢得博弈的机器的存在,将逻辑运算符理解为计算问题的运算,将逻辑公式的有效性理解为“总是可计算”问题的方案。目前的贡献给出了一个最基本的片段的可计算性逻辑的公理化的合理性和完整性证明的详细阐述。这个片段的逻辑词汇表包含所谓的并行和选择操作的操作符,它的原子代表基本问题,即标准意义上的谓词。这篇文章是自成一体的,因为它解释了所有相关的概念。虽然在技术上没有必要,但是,熟悉基础论文“Introduction to computability logic”[Annals of Pure and Applied Logic 123(2003),pp.1-99]将极大地帮助读者理解可计算性逻辑的哲学,潜在的动机,潜力和实用性,--决定当前结果价值的背景。有关该主题的在线介绍可在http://www.cis.upenn.edu/~giorgi/cl.html和http://www.csc.villanova.edu/~japaridz/CL/gsoll.html上查阅。
Soundness and completeness of the cirquent calculus system CL6 for computability logic
可计算性逻辑是可计算性的形式化理论。Japaridze的早期文章“Introduction to Cirquent Calculus and Abstract Resource Semantics”证明了可计算性逻辑的基本片段CL5的可靠性和完备性。本文将这一结果扩展到更具表现力的cirquent演算系统CL6,这是CL5和经典命题逻辑的保守扩展。
This article is a semitutorial-style survey of computability logic. An extended online version of it is maintained at http://www.csc.villanova.edu/~japaridz/CL/ .
Weighted monadic second-order logic is a weighted extension of monadic second-order logic that captures exactly the behaviour of weighted automata. Its semantics is parameterized with respect to a semiring on which the values that weighted formulas output are evaluated. Gastin and Monmege (2018) gave abstract semantics for a version of weighted monadic second-order logic to give a more general and modular proof of the equivalence of the logic with weighted automata. We focus on the abstract semantics of the logic and we give a complete axiomatization both for the full logic and for a fragment …
Proofs (sequent calculus, natural deduction) and imperative algorithms (pseudocodes) are two well-known coexisting concepts. Then what is their relationship? Our answer is that \[ imperative\ algorithms\ =\ proofs\ with\ cuts \] This observation leads to a generalization to pseudocodes which we call {\it logical pseudocodes}. It is similar to natural deduction proof of computability logic\cite{Jap03,Jap08}. Each statement in it corresponds to a proof step in natural deduction. Therefore, the merit over pseudocode is that each statement is guaranteed to be correct and safe with respect to the i…