认知逻辑与认识论之研究现状

在某种程度上说,认知逻辑似乎有些脱离一般的认识论研究。本文旨在说明介于这两个领域之间的“桥梁”依然存在。而且,事实上它们之间的联系十分紧密。文章通过分析下面的一些实例对此加以论证,即,知识和证据演算的关系,怀疑主义,信息的动态性,学习和证实,多主体或群体问题等等。作者试图通过以上分析来表明下面的观点:知识不应被定义成命题的某种本质特征,我们应当根据知识在认知活动中所起的作用来对它加以理解。     

论信念逻辑与认知逻辑的决策论基础(英文)

在本文中,我们为期望收益最大化的信念和知识提供一个逻辑——信念与认知逻辑(DEL)。这个逻辑是基于决策理论和测度论的方法建立的,在其中信念和知识不会坍塌。     

基于广义框架的概率认知逻辑

概率认知逻辑将认知和概率推理融合到同一个逻辑框架中。本文提出了一个基于广义框架的概率认知模型,并讨论了这一模型与已有两种概率认知模型的关系。基于广义框架的概率认知模型能为任意概率认知逻辑公式指派概率,因而是一种比较理想的概率认知逻辑语义模型。本文给出了一个可靠且完全的概率认知逻辑公理系统,提出并证明了概率函数存在引理,进而给出了这一逻辑的完全性证明。最后,本文运用这一逻辑刻画了混合策略博弈的两种状态,为进一步讨论混合策略博弈奠定了基础。     

从认知发展看思维和逻辑的基本类型

人类和个人对事物的认知发展过程可分为感性认知和理性认知两大阶段。思维即理性认知。思维按其意识和复杂性程度可分为直觉思维、形象思维、抽象思维和辩证思维四种基本类型。逻辑学是描述思维的产物即思想的形式结构与其规律的科学,也是为思维提供思维形式与其变形规则的模规范性科学。当代逻辑学按其产生和适用的主要思维领域不同,可分为准逻辑、形象逻辑、形式逻辑和辩证逻辑四种基本类型。     

从逻辑到认知:支持理论的视角转换

支持理论是逻辑学界和认知科学界共同关心的研究课题。逻辑学界熟知的支持理论是由英国著名哲学家L.J.科恩(L.J.Cohen)在20世纪70-80年代首先提出的。它曾经成为当时的一个热门论题,学界对这一理论的评价毁誉参半。实际上,作为一种非经典概率逻辑的支持理论,它在哲学上的意义是重大的,但是它在逻辑上存在若干缺陷。于是,学界对它的关注程度日渐减低。稍后不久,一些认知心理学家在20世纪80年代提出了一种支持理论,即著名认知心理学家特维斯基(Tversky)等提出的主     

直觉主义认知逻辑与不同程度的真

直觉主义认知逻辑IEL不仅为邱奇–费奇悖论提供了解悖思路,还促进了直觉主义认识论的研究。IEL的构建旨在遵循BHK解释,以“直觉主义知识就是证实的结果”作为核心观点,接纳A→KA和KA→??A。IEL的预期解释借助“证实”概念给出了“直觉主义知识KA的证明”的定义,并以此扩展BHK解释。但直觉主义逻辑依赖于直觉主义数学,这使得BHK解释的核心在于对构造性证明的要求,基于此,IEL的预期解释偏离了BHK解释的初衷,进而IEL未能达到预期构建目标。通过对KA作新解读,能引出直觉主义真和经典真之间不同程度的真,IEL系统的一些重要内定理也将获得新理解。此外,关于IEL系统对应问题的一个猜测被提出来。     

认知结构及发展：皮亚杰逻辑心理学的贡献

研究儿童的认知结构、揭示儿童的智慧发展规律,一直是心理学孜孜不懈地追求。在皮亚杰（JeanPiaget,1896—1980）研究的早期和中期,心理学占主导地位的是行为主义心理学、格式塔心理学和弗洛伊德主义心理学,尽管皮亚杰受格式塔心理学的影响,更加关注认知结构在认知中的主导作用,但他反对行为主义心理学“刺激一反应”（S—R）的单向关系理论,     

面向不足与复杂认知的当代归纳逻辑研究

一从定性认知到定量认知:古典归纳逻辑到现代归纳逻辑归纳逻辑是以归纳推理和归纳方法为基本内容的知识体系。归纳推理的前提是一些关于个别事物或现象的判断,而结论是关于该类事物或现象的普遍性的判断。归纳推理的结论超出了前提所断定的范     

从认知逻辑视角看西方伦理学的发展

本文希望从认知伦理学的视角出发探讨伦理学的发展,以及人类对道德问题认知的过程与人类一般认知的逻辑之间的一致性。人类认知的逻辑是由概念到判断再到推论的过程,伦理学史由德性伦理学到规范伦理学再到话语伦理学、元伦理学和新德性伦理学的过程,实际上就是人类在道德认知上从概念伦理学到判断伦理学再到推论伦理学最后回归到概念伦理学的过程。     

从方法论的角度看动态认知逻辑的研究

本文主要探讨动态认知逻辑技术结果背后的思想,着重强调其在方法论方面的一般想法。文章在公开宣告逻辑的基础上展开讨论,重点考察了归约公理的意义,揭示了其本质是在基本语言中提前解析动态信息对认知产生的影响。文章以公共知识为例,说明了并非所有的逻辑算子都能找到归约公理,有时候我们需要丰富基本语言的表达力。而且,我们从如何给出一个逻辑的角度提出,动态认知逻辑实际上是在“动态化”认知逻辑,这种动态化的方法可以应用在其他静态的逻辑系统中。我们以动态偏好逻辑为例,说明了这一过程是如何实现的。     

Logics for Epistemic Programs

We construct logical languages which allow one to represent a variety of possible types of changes affecting the information states of agents in a multi-agent setting. We formalize these changes by defining a notion of epistemic program. The languages are two-sorted sets that contain not only sentences but also actions or programs. This is as in dynamic logic, and indeed our languages are not significantly more complicated than dynamic logics. But the semantics is more complicated. In general, the semantics of an epistemic program is what we call aprogram model. This is a Kripke model of ‘actions’,representing the agents' uncertainty about the current action in a similar way that Kripke models of ‘states’ are commonly used in epistemic logic to represent the agents' uncertainty about the current state of the system. Program models induce changes affecting agents' information, which we represent as changes of the state model, called epistemic updates. Formally, an update consists of two operations: the first is called the update map, and it takes every state model to another state model, called the updated model; the second gives, for each input state model, a transition relation between the states of that model and the states of the updated model. Each variety of epistemic actions, such as public announcements or completely private announcements to groups, gives what we call an action signature, and then each family of action signatures gives a logical language. The construction of these languages is the main topic of this paper. We also mention the systems that capture the valid sentences of our logics. But we defer to a separate paper the completeness proof. The basic operation used in the semantics is called the update product. A version of this was introduced in Baltag et al. (1998), and the presentation here improves on the earlier one. The update product is used to obtain from any program model the corresponding epistemic update, thus allowing us to compute changes of information or belief. This point is of interest independently of our logical languages. We illustrate the update product and our logical languages with many examples throughout the paper.     

Free Quantified Epistemic Logics

The paper presents an epistemic logic with quantification over agents of knowledge and with a syntactical distinction between de re and de dicto occurrences of terms. Knowledge de dicto is characterized as ‘knowledge that’, and knowlegde de re as ‘knowledge of’. Transition semantics turns out to be an adequate tool to account for the distinctions introduced.     

Propositional Epistemic Logics with Quantification Over Agents of Knowledge

The paper presents a family of propositional epistemic logics such that languages of these logics are extended by quantification over modal (epistemic) operators or over agents of knowledge and extended by predicate symbols that take modal (epistemic) operators (or agents) as arguments. Denote this family by \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\). There exist epistemic logics whose languages have the above mentioned properties (see, for example Corsi and Orlandelli in Stud Log 101:1159–1183, 2013; Fitting et al. in Stud Log 69:133–169, 2001; Grove in Artif Intell 74(2):311–350, 1995; Lomuscio and Colombetti in Proceedings of ATAL 1996. Lecture Notes in Computer Science (LNCS), vol 1193, pp 71–85, 1996). But these logics are obtained from first-order modal logics, while a logic of \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\) can be regarded as a propositional multi-modal logic whose language includes quantifiers over modal (epistemic) operators and predicate symbols that take modal (epistemic) operators as arguments. Among the logics of \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\) there are logics with a syntactical distinction between two readings of epistemic sentences: de dicto and de re (between ‘knowing that’ and ‘knowing of’). We show the decidability of logics of \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\) with the help of the loosely guarded fragment (LGF) of first-order logic. Namely, we generalize LGF to a higher-order decidable loosely guarded fragment. The latter fragment allows us to construct various decidable propositional epistemic logics with quantification over modal (epistemic) operators. The family of this logics coincides with \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\). There are decidable propositional logics such that these logics implicitly contain quantification over agents of knowledge, but languages of these logics are usual propositional epistemic languages without quantifiers and predicate symbols (see Grove and Halpern in J Log Comput 3(4):345–378, 1993). Some logics of \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\) can be regarded as counterparts of logics defined in Grove and Halpern (J Log Comput 3(4):345–378, 1993). We prove that the satisfiability problem for these logics of \({\mathcal {P}\mathcal {E}\mathcal {L}}_{({ QK})}\) is Pspace-complete using their counterparts in Grove and Halpern (J Log Comput 3(4):345–378, 1993).     

Dynamic Epistemic Logics of Diffusion and Prediction in Social Networks

Studia Logica - We take a logical approach to threshold models, used to study the diffusion of opinions, new technologies, infections, or behaviors in social networks. Threshold models consist of a...     

Propositional Epistemic Logics with Quantification Over Agents of Knowledge (An Alternative Approach)

Studia Logica - In the previous paper with a similar title (see Shtakser in Stud Log 106(2):311–344, 2018), we presented a family of propositional epistemic logics whose languages are...     

Selfextensional Logics with a Conjunction

A logic is selfextensional if its interderivability (or mutual consequence) relation is a congruence relation on the algebra of formulas. In the paper we characterize the selfextensional logics with a conjunction as the logics that can be defined using the semilattice order induced by the interpretation of the conjunction in the algebras of their algebraic counterpart. Using the charactrization we provide simpler proofs of several results on selfextensional logics with a conjunction obtained in [13] using Gentzen systems. We also obtain some results on Fregean logics with conjunction.This paper is a version of the invited talk at the conference Trends in Logic III, dedicated to the memory of A. MOSTOWSKI, H. RASIOWA and C. RRAUSZER, and held in Warsaw and Ruciane-Nida from 23rd to 25th September 2005.     

Predicate Logics on Display

The paper provides a uniform Gentzen-style proof-theoretic framework for various subsystems of classical predicate logic. In particular, predicate logics obtained by adopting van Behthem's modal perspective on first-order logic are considered. The Gentzen systems for these logics augment Belnap's display logic by introduction rules for the existential and the universal quantifier. These rules for x and x are analogous to the display introduction rules for the modal operators and and do not themselves allow the Barcan formula or its converse to be derived. En route from the minimal modal predicate logic to full first-order logic, axiomatic extensions are captured by purely structural sequent rules.     

Memory as a Generative Epistemic Source

It is widely assumed that memory has only the capacity to preserve epistemic features that have been generated by other sources. Specifically, if S knows (justifiedly believes/rationally believes) that p via memory at T2, then it is argued that (i) S must have known (justifiedly believed/rationally believed) that p when it was originally acquired at T1, and (ii) S must have acquired knowledge that p (justification with respect to p/rationality with respect to p) at T1 via a non-memorial source. Thus, according to this view, memory cannot make an unknown proposition known, an unjustified belief justified, or an irrational belief rational–it can only preserve what is already known, justified, or rational. In this paper, I argue that condition (i) is false and, a fortiori , that condition (ii) is false. Hence, I show that, contrary to received wisdom in contemporary epistemology, memory can function as a generative epistemic source.