首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
条件句系统通常用择类语义来刻画,此语义对条件句逻辑来说是标准的。一个择类模型可以用一个三元组(W,f,V)来表示,其中W≠Φ,f是从P(W)×W到P(W)中的择类函数,且V是从一命题变元集PV到P(W)中的赋值函数。本文我们提出一个更新语义,它保留择类框架,但V被从PV到P(W)^P(W)中的一个更新函数代替,因为更新函数能表示动态命题而赋值函数则不能。最后我们证明一个条件句系统相对这样的语义有框架可靠性。  相似文献   

2.
There has been considerable work on practical reasoning in artificial intelligence and also in philosophy. Typically, such reasoning includes premises regarding means–end relations. A clear semantics for such relations is needed in order to evaluate proposed syllogisms. In this paper, we provide a formal semantics for means–end relations, in particular for necessary and sufficient means–end relations. Our semantics includes a non-monotonic conditional operator, so that related practical reasoning is naturally defeasible. This work is primarily an exercise in conceptual analysis, aimed at clarifying and eventually evaluating existing theories of practical reasoning (pending a similar analysis regarding desires, intentions and other relevant concepts). “They were in conversation without speaking. They didn’t need to speak. They just changed reality so that they had spoken.” Terry Pratchett, Reaper Man  相似文献   

3.
This paper sets out a semantics for C.I. Lewis's logic S2 based on the ontology of his 1923 paper ‘Facts, Systems, and the Unity of the World’. In that article, worlds are taken to be maximal consistent systems. A system, moreover, is a collection of facts that is closed under logical entailment and conjunction. In this paper, instead of defining systems in terms of logical entailment, I use certain ideas in Lewis's epistemology and philosophy of logic to define a class of models in which systems are taken to be primitive elements but bear certain relations to one another. I prove soundness and completeness for S2 over this class of models and argue that this semantics makes sense of at least a substantial fragment of Lewis's logical theory.  相似文献   

4.
In this paper we provide an interpretation of Aristotle's rule for the universal quantifier in Topics Θ 157a34–37 and 160b1–6 in terms of Paul Lorenzen's dialogical logic. This is meant as a contribution to the rehabilitation of the role of dialectic within the Organon. After a review of earlier views of Aristotle on quantification, we argue that this rule is related to the dictum de omni in Prior Analytics A 24b28–29. This would be an indication of the dictum’s origin in the context of dialectical games. One consequence of our approach is a novel explanation of the doctrine of the existential import of the quantifiers in dialectical terms. After a brief survey of Lorenzen's dialogical logic, we offer a set of rules for dialectical games based on previous work by Castelnérac and Marion, to which we add here the rule for the universal quantifier, as interpreted in terms of its counterpart in dialogical logic. We then give textual evidence of the use of that rule in Plato's dialogues, thus showing that Aristotle only made explicit a rule already implicit in practice, while providing a new interpretation of ‘epagogic’ arguments. Finally, we show how a proper understanding of that rule involves further rules concerning counterexamples and delaying tactics, stressing again the parallels with dialogical logic.  相似文献   

5.
In this paper, we propose a game semantics for the (associative) Lambek calculus. Compared to the implicational fragment of intuitionistic propositional calculus, the semantics deals with two features of the logic: absence of structural rules, as well as directionality of implication. We investigate the impact of these variations of the logic on its game semantics. Presented by Wojciech Buszkowski  相似文献   

6.
In the context of truth-functional propositional many-valued logics, Hájek’s Basic Fuzzy Logic BL [14] plays a major rôle. The completeness theorem proved in [7] shows that BL is the logic of all continuous t-norms and their residua. This result, however, does not directly yield any meaningful interpretation of the truth values in BL per se. In an attempt to address this issue, in this paper we introduce a complete temporal semantics for BL. Specifically, we show that BL formulas can be interpreted as modal formulas over a flow of time, where the logic of each instant is ?ukasiewicz, with a finite or infinite number of truth values. As a main result, we obtain validity with respect to all flows of times that are non-branching to the future, and completeness with respect to all finite linear flows of time, or to an appropriate single infinite linear flow of time. It may be argued that this reduces the problem of establishing a meaningful interpretation of the truth values in BL logic to the analogous problem for ?ukasiewicz logic.  相似文献   

7.
We present a compositional semantics for first-order logic with imperfect information that is equivalent to Sevenster and Sandu’s equilibrium semantics (under which the truth value of a sentence in a finite model is equal to the minimax value of its semantic game). Our semantics is a generalization of an earlier semantics developed by the first author that was based on behavioral strategies, rather than mixed strategies.  相似文献   

8.
9.
The standard account of modal expressions in natural language analyzes them as quantifiers over a set of possible worlds determined by the evaluation world and an accessibility relation. A number of authors have recently argued for an alternative account according to which modals are analyzed as quantifying over a domain of possible worlds that is specified directly in the points of evaluation. But the new approach only handles the data motivating it if it is supplemented with a non-standard account of attitude verbs and conditionals. It can be shown the the relational account handles the same data equally well if it too is supplemented with a non-standard account of such expressions.  相似文献   

10.
King  Jeffrey C. 《Mind》2006,115(460):1023-1058
  相似文献   

11.
Studia Logica - We propose a new perspective on logics of computation by combining instantial neighborhood logic $$\mathsf {INL}$$ with bisimulation safe operations adapted from $$\mathsf {PDL}$$ ....  相似文献   

12.
Allwein  Gerard  MacCaull  Wendy 《Studia Logica》2001,68(2):173-228
Gelfand quantales are complete unital quantales with an involution, *, satisfying the property that for any element a, if a b a for all b, then a a* a = a. A Hilbert-style axiom system is given for a propositional logic, called Gelfand Logic, which is sound and complete with respect to Gelfand quantales. A Kripke semantics is presented for which the soundness and completeness of Gelfand logic is shown. The completeness theorem relies on a Stone style representation theorem for complete lattices. A Rasiowa/Sikorski style semantic tableau system is also presented with the property that if all branches of a tableau are closed, then the formula in question is a theorem of Gelfand Logic. An open branch in a completed tableaux guarantees the existence of an Kripke model in which the formula is not valid; hence it is not a theorem of Gelfand Logic.  相似文献   

13.
The purpose of the present paper is to provide a way of understanding systems of logic of essence by introducing a new semantic framework for them. Three central results are achieved: first, the now standard Fitting semantics for the propositional logic of evidence is adapted in order to provide a new, simplified semantics for the propositional logic of essence; secondly, we show how it is possible to construe the concept of necessary truth explicitly by using the concept of essential truth; finally, Fitting semantics is adapted in order to present a simplified semantics for the quantified logic of essence.  相似文献   

14.
This paper introduces a generalized version of inquisitive semantics, denoted as GIS, and concentrates especially on the role of disjunction in this general framework. Two alternative semantic conditions for disjunction are compared: the first one corresponds to the so-called tensor operator of dependence logic, and the second one is the standard condition for inquisitive disjunction. It is shown that GIS is intimately related to intuitionistic logic and its Kripke semantics. Using this framework, it is shown that the main results concerning inquisitive semantics, especially the axiomatization of inquisitive logic, can be viewed as particular cases of more general phenomena. In this connection, a class of non-standard superintuitionistic logics is introduced and studied. These logics share many interesting features with inquisitive logic, which is the strongest logic of this class.  相似文献   

15.
Semantics for existential graphs   总被引:1,自引:0,他引:1  
This paper examines Charles Peirce's graphical notation for first-order logic with identity. The notation forms a part of his system of existential graphs, which Peirce considered to be his best work in logic. In this paper a Tarskian semantics is provided for the graphical system.  相似文献   

16.
17.
18.
The paper presents the two main assumptions of Attentional Semantics—(A) and (B), and its main aim (C). (A) Conscious experience is determined by attention: there cannot be consciousness without attention. Consciousness is explained as the product of attentional activity. Attentional activity can be performed thanks to a special kind of energy: nervous energy. This energy is supplied by the organ of attention. When we perform attentional activity, we use our nervous energy. This activity directly affects the organ of attention, causing a variation in the state of the nervous energy. This variation constitutes the phenomenal aspect of consciousness. (B) Words are tools to pilot attention. The meanings of words isolate, de-contextualize, “freeze” and classify in an articulated system the ever-changing and multiform stream of our conscious experiences. Each meaning is composed of the sequence of invariable elements that, independently of any individual occurrence of a given conscious experience, are responsible for the production of any instance of that conscious experience. The elements composing the meanings of words are attentional operations: each word conveys the condensed instructions on the attentional operations one has to perform if one wants to consciously experience what is expressed through and by it. (C) Attentional Semantics aims at finding the attentional instruction conveyed by the meanings of words. To achieve this goal, it tries: (1) to identify the sequence of the elementary conscious experiences that invariably accompany, and are prompted by, the use of the word being analyzed; (2) to describe these conscious experiences in terms of the attentional operations that are responsible for their production; and (3) to identify the unconscious and non-conscious operations that, directly or indirectly, serve either as the support that makes it possible for the attentional operations to take place, be completed, and occur in a certain way, or as the necessary complement that makes it possible to execute and implement the activities determined and triggered by the conscious experiences. The origins of Attentional Semantics are also presented, and the methodological problems researchers encounter when analyzing meanings in attentional terms are discussed. Finally, a brief comparison with the other kinds of semantics is made.  相似文献   

19.
本文介绍由塔斯基的立体几何导出的球态语义学,并将其应用于自然语言中的动词体现象。球态语义学特别适合应用于英语的进行体。这种方法有以下优点(i)它扩展了区间式语义,并同时避免了其缺陷,(ii)它解决了未完成体难题,(iii)它的解决方法无需诉诸最终结果策略。逻辑方法一般被认为难于处理自然语言的动词体问题。基于点的时间结构以及建立在该结构之上的经典普莱尔时态逻辑([18])太弱了。而基于区间的时态语义则缺乏足够的表达力,并且难以解释进行体([4,8]).本文给出一种新的基于球上整体-部分关系概念的模型和时态语义。这种球态语义学建基于塔斯基1927年引入的立体几何之上。与基于点和基于区间的语义不同,在球态语义学中很多动词体区分都由统一的逻辑方法刻画。在一个由封闭球构成的论域中,可达关系由相切性概念给出。相应地,我们可定义外切、内切、外径、内径以及同心等基本概念。与区间式语义不同,球是论域的初始概念,球态语义学不是在时间段而是在球中对事件赋值。因此,仅将时间区间作为初始概念而不承认其端点初性性的问题不复存在。英语中的进行体由球上的连续行动来刻画。行动是非终止的,只要球没有由外切相离。相应地,外切相离刻车动作完成。我们区分在均匀球和非均匀球中发生事件的整体-部分关系。非持续动作视为直径为零的同心球。球态语义学根据动作或执行完成的时刻来定义时间概念,其中不需要时间端点的概念。在保持与基于区间的时间模型类似的基础上,球态语义学暗示了一种关于可能世界的定性概念,并且它有利于解决时间的循环概念问题。  相似文献   

20.
Correia  Fabrice 《Studia Logica》2004,77(1):87-104
In 1977, R. B. Angell presented a logic for analytic containment, a notion of relevant implication stronger than Anderson and Belnap's entailment. In this paper I provide for the first time the logic of first degree analytic containment, as presented in [2] and [3], with a semantical characterization—leaving higher degree systems for future investigations. The semantical framework I introduce for this purpose involves a special sort of truth-predicates, which apply to pairs of collections of formulas instead of individual formulas, and which behave in some respects like Gentzen's sequents. This semantics captures very general properties of the truth-functional connectives, and for that reason it may be used to model a vast range of logics. I briefly illustrate the point with classical consequence and Anderson and Belnap's tautological entailments.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号