Program Constructions that are Safe for Bisimulation

It has been known since the seventies that the formulas of modal logic are invariant for bisimulations between possible worlds models — while conversely, all bisimulation-invariant first-order formulas are modally definable. In this paper, we extend this semantic style of analysis from modal formulas to dynamic program operations. We show that the usual regular operations are safe for bisimulation, in the sense that the transition relations of their values respect any given bisimulation for their arguments. Our main result is a complete syntactic characterization of all first-order definable program operations that are safe for bisimulation. This is a semantic functional completeness result for programming, which may be contrasted with the more usual analysis in terms of computational power. The 'Safety Theorem' can be modulated in several ways. We conclude with a list of variants, extensions, and further developments.     

模态逻辑的集合论语义与互模拟不变性

含有命题变元的非良基集合能够被看作解释模态语言的模型。任给非良基集合a,一个命题变元p在a上真当且仅当p属于a。命题联结词的解释与古典命题逻辑相同。一个公式3A在a上真当且仅当存在集合b属于a,使得A在b上是真的。在一个集合中,属于关系被看作可及关系。在这种思想下,我们可以定义从模态语言到一阶集合论语言的标准翻译。对任意模态公式A和集合变元x,可以递归定义一阶集合论语言的公式ST(A,x)。在关系语义学下,van Benthem刻画定理是说,在带有唯一的二元关系符号R的一阶语言中,任何一阶公式等价于某个模态公式的标准翻译当且仅当这个一阶公式在互模拟下保持不变。因此,模态语言是该一阶关系语言的互模拟不变片段。同样,我们可以在集合上定义互模拟关系,证明van Benthem刻画定理对于集合论语义和集合上的互模拟不变片段成立,即模态语言是一阶集合论语言的集合互模拟不变片段。     

Dynamic Modalities

A new modal logic containing four dynamic modalities with the following informal reading is introduced: ${\square^\forall}$ – always necessary, ${\square^\exists}$ – sometimes necessary, and their duals – ${\diamondsuit^\forall}$ – always possibly, and ${\diamondsuit^\exists}$ – sometimes possibly. We present a complete axiomatization with respect to the intended formal semantics and prove decidability via fmp.     

The Agentive Modalities

A number of philosophical projects require a proper understanding of the modal aspects of agency, or of what I call ‘the agentive modalities.’ I propose a general account of the agentive modalities, one which takes as its primitive the decision‐theoretic notion of an option. I relate this account to the standard semantics for ‘can’ and to the viability of some positions in the free will debates.     

Kant's Modalities of Judgment

Abstract: This paper proposes a way to understand Kant's modalities of judgment—problematic, assertoric, and apodeictic—in terms of the location of a judgment in an inference. Other interpretations have tended to understand these modalities of judgment in terms of one or other conventional notion of modality. For example, Mattey (1986) argues that we should take them to be connected to notions of epistemic or doxastic modality. I shall argue that this is wrong, and that these kinds of interpretation of the modality of judgments cannot be reconciled with a key claim made by Kant, namely, that the modality of a judgment does not contribute to its content, and has nothing to do with the matter that is judged. I offer an alternative interpretation based upon Kant's explicating these modalities in terms of the location of a judgment in an inference, whereby the modality of a judgment is determined by the role a judgment plays in a given course of reasoning. If I am right, then Kant in fact presents an intriguing thesis pertaining to the inferential status and potential of all our judgments.     

Projection across Sensory Modalities

Question is raised as to whether we are not setting our sights too high in trying to understand personality. Difficulty of understanding the “whole” personality is related to the fact that half of what is determining it at any given time is situationally defined and the other half is tied up with almost invisible inner processes. Homage is paid to Henry Murray for having put us on the right path.     

Cut-Elimination for Quantified Conditional Logic

A semantic embedding of quantified conditional logic in classical higher-order logic is utilized for reducing cut-elimination in the former logic to existing results for the latter logic. The presented embedding approach is adaptable to a wide range of other logics, for many of which cut-elimination is still open. However, special attention has to be payed to cut-simulation, which may render cut-elimination as a pointless criterion.     

Non-Adjunctive Inference and Classical Modalities

The article focuses on representing different forms of non-adjunctive inference as sub-Kripkean systems of classical modal logic, where the inference from □A and □B to □A∧B fails. In particular we prove a completeness result showing that the modal system that Schotch and Jennings derive from a form of non-adjunctive inference in (Schotch and Jennings, 1980) is a classical system strictly stronger than EMN and weaker than K (following the notation for classical modalities presented in Chellas, 1980). The unified semantical characterization in terms of neighborhoods permits comparisons between different forms of non-adjunctive inference. For example, we show that the non-adjunctive logic proposed in (Schotch and Jennings, 1980) is not adequate in general for representing the logic of high probability operators. An alternative interpretation of the forcing relation of Schotch and Jennings is derived from the proposed unified semantics and utilized in order to propose a more fine-grained measure of epistemic coherence than the one presented in (Schotch and Jennings, 1980). Finally we propose a syntactic translation of the purely implicative part of Jaśkowski's system D₂ into a classical system preserving all the theorems (and non-theorems) explicilty mentioned in (Jaśkowski, 1969). The translation method can be used in order to develop epistemic semantics for a larger class of non-adjunctive (discursive) logics than the ones historically investigated by Jaśkowski.     

条件推理的条件概率模型述评

该文从理论模型和实验范式两个方面对Oaksford等人提出的条件推理概率模型作了综合评述,并充分肯定该模型将演绎推理与归纳推理结合起来进行研究对推理心理学的发展所作出的重要贡献。     

A Structural Blueprint for Group Facilitators: Three Group Modalities

This article provides a conceptual model, typology, or blueprint to unify and more clearly understand the spectrum of task-, socio-, and psycho-group processes used by guidance and counseling personnel. The authors provide a structure for group leaders to follow within their various group forms or modalities.     

Some Embedding Theorems for Conditional Logic

We prove some embedding theorems for classical conditional logic, covering ‘finitely cumulative’ logics, ‘preferential’ logics and what we call ‘semi-monotonic’ logics. Technical tools called ‘partial frames’ and ‘frame morphisms’ in the context of neighborhood semantics are used in the proof.     

Grafting Modalities onto Substructural Implication Systems

We investigate the semantics of the logical systems obtained by introducing the modalities and into the family of substructural implication logics (including relevant, linear and intuitionistic implication). Then, in the spirit of the LDS (Labelled Deductive Systems) methodology, we "import" this semantics into the classical proof system KE. This leads to the formulation of a uniform labelled refutation system for the new logics which is a natural extension of a system for substructural implication developed by the first two authors in a previous paper.     

A Comparison of Modalities in Modeling

Organizational display rules (e.g., “service with a smile”) have had mixed relationships with employee emotional labor—either in the form of “bad faith” surface acting (suppressing or faking expressions) or “good faith” deep acting (modifying inner feelings). We draw on the motivational perspective of emotional labor to argue that individual differences in customer orientation will directly and indirectly relate to these acting strategies in response to display rules. With a survey of more than 500 working adults in customer contact positions, and controlling for affective disposition, we find that customer orientation directly increases “good faith” acting while it moderates the relationship of display rules with “bad faith” acting.     

Conditional theories

This paper introduces conditional logic, that is, a variant of free logic where the existence condition of a function is defined by a formula of the formal language. Syntax and semantics are developed. A completeness theorem is given.