Naming and identity in epistemic logic part II: a first-order logic for naming

In a recent paper Lakemeyer and Levesque proposed a first-order logic of limited belief to characterize the beliefs of a knowledge base (\KB). Among other things, they show that their model of belief is expressive, eventually complete, and tractable. This means, roughly, that a \KB\ may consist of arbitrary first-order sentences, that any sentence which is logically entailed by the \KB\ is eventually believed, given enough reasoning effort, and that reasoning is tractable under reasonable assumptions. One downside of the proposal is that epistemic states are defined in terms of sets of clauses, possibly containing variables, giving the logic a distinct syntactic flavour compared to the more traditional possible-world semantics found in the literature on epistemic logic. In this paper we show that the same properties as above can be obtained by defining epistemic states as sets of three-valued possible worlds. This way we are able to shed new light on those properties by recasting them using the more familiar notion of truth over possible worlds.

Download Full-text

Interactions between Knowledge and Time in a First-Order Logic for Multi-Agent Systems: Completeness Results

Journal of Artificial Intelligence Research ◽

10.1613/jair.3547 ◽

2012 ◽

Vol 45 ◽

pp. 1-45 ◽

Cited By ~ 12

Author(s):

F. Belardinelli ◽

A. Lomuscio

Keyword(s):

Epistemic Logic ◽

Order Logic ◽

First Order Logic ◽

Multi Agent Systems ◽

Perfect Recall ◽

Initial State ◽

Agent Systems ◽

First Order ◽

Multi Agent ◽

Order Extension

We investigate a class of first-order temporal-epistemic logics for reasoning about multi-agent systems. We encode typical properties of systems including perfect recall, synchronicity, no learning, and having a unique initial state in terms of variants of quantified interpreted systems, a first-order extension of interpreted systems. We identify several monodic fragments of first-order temporal-epistemic logic and show their completeness with respect to their corresponding classes of quantified interpreted systems.

Download Full-text

First-Order Logic Reasoning Support for the Semantic Web

Journal of Software ◽

10.3724/sp.j.1001.2008.03091 ◽

2009 ◽

Vol 19 (12) ◽

pp. 3091-3099 ◽

Cited By ~ 1

Author(s):

Gui-Hong XU ◽

Jian ZHANG

Keyword(s):

Semantic Web ◽

Order Logic ◽

First Order Logic ◽

First Order ◽

Logic Reasoning

Download Full-text

Boolean-valued structures

10.1093/oso/9780198790396.003.0013 ◽

2018 ◽

Author(s):

Tim Button ◽

Sean Walsh

Keyword(s):

Model Theory ◽

Order Logic ◽

First Order Logic ◽

Inference Rules ◽

Mathematical Concepts ◽

Semantic Framework ◽

First Order ◽

Standard Models ◽

Boolean Valued Model ◽

Semantic Values

Chapters 6-12 are driven by questions about the ability to pin down mathematical entities and to articulate mathematical concepts. This chapter is driven by similar questions about the ability to pin down the semantic frameworks of language. It transpires that there are not just non-standard models, but non-standard ways of doing model theory itself. In more detail: whilst we normally outline a two-valued semantics which makes sentences True or False in a model, the inference rules for first-order logic are compatible with a four-valued semantics; or a semantics with countably many values; or what-have-you. The appropriate level of generality here is that of a Boolean-valued model, which we introduce. And the plurality of possible semantic values gives rise to perhaps the ‘deepest’ level of indeterminacy questions: How can humans pin down the semantic framework for their languages? We consider three different ways for inferentialists to respond to this question.

Download Full-text

GAMES AND CARDINALITIES IN INQUISITIVE FIRST-ORDER LOGIC

The Review of Symbolic Logic ◽

10.1017/s1755020321000198 ◽

2021 ◽

pp. 1-28

Author(s):

IVANO CIARDELLI ◽

GIANLUCA GRILLETTI

Keyword(s):

Order Logic ◽

First Order Logic ◽

First Order

Download Full-text

Extensions in graph normal form

Logic Journal of IGPL ◽

10.1093/jigpal/jzaa054 ◽

2020 ◽

Author(s):

Michał Walicki

Keyword(s):

Normal Form ◽

Fixed Points ◽

Propositional Logic ◽

Order Logic ◽

First Order Logic ◽

First Order ◽

Special Cases

Abstract Graph normal form, introduced earlier for propositional logic, is shown to be a normal form also for first-order logic. It allows to view syntax of theories as digraphs, while their semantics as kernels of these digraphs. Graphs are particularly well suited for studying circularity, and we provide some general means for verifying that circular or apparently circular extensions are conservative. Traditional syntactic means of ensuring conservativity, like definitional extensions or positive occurrences guaranteeing exsitence of fixed points, emerge as special cases.

Download Full-text

Relational Chase Procedures Interpreted as Resolution with Paramodulation1

Fundamenta Informaticae ◽

10.3233/fi-1991-15203 ◽

1991 ◽

Vol 15 (2) ◽

pp. 123-138

Author(s):

Joachim Biskup ◽

Bernhard Convent

Keyword(s):

Alternative Interpretation ◽

Order Logic ◽

First Order Logic ◽

Inference Problem ◽

First Order ◽

Inference Problems ◽

The One ◽

The Relationship ◽

Theoretical Foundations ◽

Insight Into

In this paper the relationship between dependency theory and first-order logic is explored in order to show how relational chase procedures (i.e., algorithms to decide inference problems for dependencies) can be interpreted as clever implementations of well known refutation procedures of first-order logic with resolution and paramodulation. On the one hand this alternative interpretation provides a deeper insight into the theoretical foundations of chase procedures, whereas on the other hand it makes available an already well established theory with a great amount of known results and techniques to be used for further investigations of the inference problem for dependencies. Our presentation is a detailed and careful elaboration of an idea formerly outlined by Grant and Jacobs which up to now seems to be disregarded by the database community although it definitely deserves more attention.

Download Full-text

Formula size games for modal logic and μ-calculus

Journal of Logic and Computation ◽

10.1093/logcom/exz025 ◽

2019 ◽

Vol 29 (8) ◽

pp. 1311-1344 ◽

Cited By ~ 2

Author(s):

Lauri T Hella ◽

Miikka S Vilander

Keyword(s):

Modal Logic ◽

Optimal Strategy ◽

Order Logic ◽

First Order Logic ◽

Kripke Models ◽

First Order ◽

Modal Operators ◽

Crucial Difference ◽

Definition Of ◽

Person Game

Abstract We propose a new version of formula size game for modal logic. The game characterizes the equivalence of pointed Kripke models up to formulas of given numbers of modal operators and binary connectives. Our game is similar to the well-known Adler–Immerman game. However, due to a crucial difference in the definition of positions of the game, its winning condition is simpler, and the second player does not have a trivial optimal strategy. Thus, unlike the Adler–Immerman game, our game is a genuine two-person game. We illustrate the use of the game by proving a non-elementary succinctness gap between bisimulation invariant first-order logic $\textrm{FO}$ and (basic) modal logic $\textrm{ML}$. We also present a version of the game for the modal $\mu $-calculus $\textrm{L}_\mu $ and show that $\textrm{FO}$ is also non-elementarily more succinct than $\textrm{L}_\mu $.

Download Full-text