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。     

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。     

从动态认知逻辑的角度看偏好——刘奋荣《动态偏好逻辑》评介

《动态偏好逻辑》一书是国家社会科学基金青年项目（项目编号：04CZX001）的优秀成果,也是刘奋荣博士在荷兰阿姆斯特丹大学逻辑、语言和计算研究所（ILLC）从事博士项目研究的主体内容。全书分为七章：第一章引论;     

博弈论中重复可允许算法的认知分析

博弈论中重复可允许(Iterated Admissibilty)算法对于快速约简博弈模型、寻找合理置信的纳什均衡具有重要意义,但该算法的认知基础存在悖论。本文构建一个完备的博弈认知逻辑系统EL_G,利用该系统语言描述博弈相关概念和性质,使得我们可以基于EL_G逻辑刻画重复可允许算法,从而达到为该算法提供合理的认知基础,解决算法背后的认知悖论的目的。     

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。     

The Surprise Examination in Dynamic Epistemic Logic

We examine the paradox of the surprise examination using dynamic epistemic logic. This logic contains means of expressing epistemic facts as well as the effects of learning new facts, and is therefore a natural framework for representing the puzzle. We discuss a number of different interpretations of the puzzle in this context, and show how the failure of principle of success, that states that sentences, when learned, remain to be true and come to be believed, plays a central role in understanding the puzzle.     

Intensional Protocols for Dynamic Epistemic Logic

Journal of Philosophical Logic - In dynamical multi-agent systems, agents are controlled by protocols. In choosing a class of formal protocols, an implicit choice is made concerning the types of...     

Skepticism and Epistemic Logic

This essay attempts to implement epistemic logic through a non-classical inference relation. Given that relation, an account of '(the individual) a knows that A' is constructed as an unfamiliar non-normal modal logic. One advantage to this approach is a new analysis of the skeptical argument.     

Epistemic Operators in Dependence Logic

The properties of the ${\forall^{1}}$ quantifier defined by Kontinen and Väänänen in [13] are studied, and its definition is generalized to that of a family of quantifiers ${\forall^{n}}$ . Furthermore, some epistemic operators δ ⁿ for Dependence Logic are also introduced, and the relationship between these ${\forall^{n}}$ quantifiers and the δ ⁿ operators are investigated. The Game Theoretic Semantics for Dependence Logic and the corresponding Ehrenfeucht- Fraissé game are then adapted to these new connectives. Finally, it is proved that the ${\forall^{1}}$ quantifier is not uniformly definable in Dependence Logic, thus answering a question posed by Kontinen and Väänänen in the above mentioned paper.     

Logic Based Merging

Belief merging aims at combining several pieces of information coming from different sources. In this paper we review the works on belief merging of propositional bases. We discuss the relationship between merging, revision, update and confluence, and some links between belief merging and social choice theory. Finally we mention the main generalizations of these works in other logical frameworks.     

Williamson on Gettier Cases and Epistemic Logic

Abstract

Timothy Williamson has fruitfully exploited formal resources to shed considerable light on the nature of knowledge. In the paper under examination, Williamson turns his attention to Gettier cases, showing how they can be motivated formally. At the same time, he disparages the kind of justification he thinks gives rise to these cases. He favors instead his own notion of justification for which Gettier cases cannot arise. We take issue both with his disparagement of the kind of justification that figures in Gettier cases and the specifics of the formal motivation.     

An Internal Version of Epistemic Logic

Representing an epistemic situation involving several agents obviously depends on the modeling point of view one takes. We start by identifying the types of modeling points of view which are logically possible. We call the one traditionally followed by epistemic logic the perfect external approach, because there the modeler is assumed to be an omniscient and external observer of the epistemic situation. In the rest of the paper we focus on what we call the internal approach, where the modeler is one of the agents involved in the situation. For this approach we propose and axiomatize a logical formalism based on epistemic logic. This leads us to formalize some intuitions about the internal approach and about its connections with the external ones. Finally, we show that our internal logic is decidable and PSPACE-complete.