271 research outputs found
Classical logic, argument and dialectic
Get PDFA well studied instantiation of Dung's abstract theory of argumentation yields argumentation-based characterisations of non-monotonic inference over possibly inconsistent sets of classical formulae. This provides for single-agent reasoning in terms of argument and counter-argument, and distributed non-monotonic reasoning in the form of dialogues between computational and/or human agents. However, features of existing formalisations of classical logic argumentation (Cl-Arg) that ensure satisfaction of rationality postulates, preclude applications of Cl-Arg that account for real-world dialectical uses of arguments by resource-bounded agents. This paper formalises dialectical classical logic argumentation that both satisfies these practical desiderata and is provably rational. In contrast to standard approaches to Cl-Arg we: 1) draw an epistemic distinction between an argument's premises accepted as true, and those assumed true for the sake of argument, so formalising the dialectical move whereby arguments’ premises are shown to be inconsistent, and avoiding the foreign commitment problem that arises in dialogical applications; 2) provide an account of Cl-Arg suitable for real-world use by eschewing the need to check that an argument's premises are subset minimal and consistent, and identifying a minimal set of assumptions as to the arguments that must be constructed from a set of formulae in order to ensure that the outcome of evaluation is rational. We then illustrate our approach with a natural deduction proof theory for propositional classical logic that allows measurement of the ‘depth’ of an argument, such that the construction of depth-bounded arguments is a tractable problem, and each increase in depth naturally equates with an increase in the inferential capabilities of real-world agents. We also provide a resource-bounded argumentative characterisation of non-monotonic inference as defined by Brewka's Preferred Subtheories
A Study of Argumentative Characterisations of Preferred Subtheories
No full textClassical logic argumentation (Cl-Arg) under the stable semantics yields argumentative characterisa- tions of non-monotonic inference in Preferred Sub- theories. This paper studies these characterisations under both the standard approach to Cl-Arg, and a recent dialectical approach that is provably rational under resource bounds. Two key contributions are made. Firstly, the preferred extensions are shown to coincide with the stable extensions. This means that algorithms and proof theories for the admissible semantics can now be used to decide credulous inference in Preferred Subtheories. Secondly, we show that as compared with the standard approach, the grounded semantics applied to the dialectical approach more closely approximates sceptical inference in Preferred Subtheories
Additive Manufacturing and Green Information Systems as Technological Capabilities for Firm Performance
No full textGiven the importance of environmental objectives, companies are continuously trying to achieve them through different means and technologies are not an exception. Companies are increasingly using information systems (soft side) coupled with manufacturing (hard side) technologies to achieve market and operational performance. Therefore, this study investigates the role of green information systems (GIS) and additive manufacturing (AM) in the market and operational performance achievement of an organization. This study explores if the role of GIS and AM is influenced by firm size and number of employees in the organization with the lens of organizational information processing theory. Through survey instrument, data from 211 respondents are collected and analysis is performed using structural equation modelling. Findings indicate that GIS is critical to overall performance as compared to AM. In addition, top management facilitates extension of business activities significantly as compared to internal operations. Control orientation works best for new technologies like GIS and AM. The study offers an array of scope for theoretical and practical implications to utilize GIS and emerging technologies like AM to achieve greater market and operational performance. Further, the study offers implications for AM and GIS professionals and researchers. The study contributes in integrating manufacturing and information systems to facilitate faster technological and information processing capabilities
A Fully Rational Account of Structured Argumentation Under Resource Bounds
Get PDFASPIC+ is an established general framework for argumentation and non-monotonic reasoning. However ASPIC+ does not satisfy the non-contamination rationality postulates, and moreover, tacitly assumes unbounded resources when demonstrating satisfaction of the consistency postulates. In this paper we present a new version of ASPIC+ – Dialectial ASPIC+ – that is fully rational under resource bounds
Towards Depth-Bounded Natural Deduction for Classical First-order Logic
Get PDFIn this paper we lay the foundations of a new proof-theory for classical first-order logic that allows for a natural characterization of a notion of inferential depth. The approach we propose here aims towards extending the proof-theoretical framework presented in [6] by combining it with some ideas inspired by Hintikka’s work [18]. Unlike standard natural deduction, in this framework the inference rules that fix the meaning of the logical operators are symmetrical with respect to assent and dissent and do not involve the discharge of formulas. The only discharge rule is a classical dilemma rule whose nested applications provide a sensible measure of inferential depth. The result is a hierarchy of decidable depth-bounded approximations of classical first-order logic that expands the hierarchy of tractable approximations of Boolean logic investigated in [11, 10, 7]
A dialectical formalisation of preferred subtheories reasoning under resource bounds
Get PDFDialectical Classical Argumentation (Dialectical Cl-Arg) has been shown to satisfy rationality postulates under resource bounds. In particular, the consistency and non-contamination postulates are satisfied despite dropping the assumption of logical omniscience and the consistency and subset minimality checks on arguments' premises that are deployed by standard approaches to Cl-Arg. This paper studies Dialectical Cl-Arg's formalisation of Preferred Subtheories (PS) non-monotonic reasoning under resource bounds. The contribution of this paper is twofold. First, we establish soundness and completeness for Dialectical Cl-Arg's credulous consequence relation under the preferred semantics and credulous PS consequences. This result paves the way for the use of argument game proof theories and dialogues that establish membership of arguments in admissible (and so preferred) extensions, and hence the credulous PS consequences of a belief base. Second, we refine the non-standard characteristic function for Dialectical Cl-Arg, and use this refined function to show soundness for Dialectical Cl-Arg consequences under the grounded semantics and resource-bounded sceptical PS consequence. We provide a counterexample that shows that completeness does not hold. However, we also show that the grounded consequences defined by Dialectical Cl-Arg strictly subsume the grounded consequences defined by standard Cl-Arg formalisations of PS, so that we recover sceptical PS consequences that one would intuitively expect to hold
Extending Dialectical Classical Logic Argumentation with Unrestricted Rebut and Occam Razor Defeats
Get PDFDialectical Classical Logic Argumentation (D-Cl-Arg) formalises maxiconsistent non-monotonic reasoning under the practical assumption that agents have bounded resources for classical inference, and that agents do not typically check arguments’ premises for subset minimality and consistency. However, D-Cl-Arg still satisfies all rationality postulates. Moreover D-Cl-Arg accommodates uses of argument characteristic of dialectical practice. This paper extends D-Cl-Arg to accommodate further dialectical uses of argument; in particular unrestricted rebuts on the deductively derived conclusions of arguments, and Occam Razor defeats that dialectically demonstrate that an argument makes use of redundant premises. We show that all rationality postulates are still satisfied, while relaxing constraints on preference relations that were previously required to prove rationality
A rational account of classical logic argumentation for real-world agents
Get PDFClassical logic based argumentation (ClAr) characterises single agent non-monotonic reasoning and enables distributed non-monotonic reasoning amongst agents in dialogues. However, features of ClAr that have been shown sufficient to ensure satisfaction of rationality postulates, preclude their use by resource bounded agents reasoning individually, or dialectically in real-world dialogue. This paper provides a new formalisation of ClAr that is both suitable for such uses and satisfies the rationality postulates. We illustrate by providing a rational dialectical characterisation of Brewka’s non- monotonic Preferred Subtheories defined under the assumption of restricted inferential capabilities
Argument mining: A machine learning perspective
No full textArgument mining has recently become a hot topic, attracting the interests of several and diverse research communities, ranging from artificial intelligence, to computational linguistics, natural language processing, social and philosophical sciences. In this paper, we attempt to describe the problems and challenges of argument mining from a machine learning angle. In particular, we advocate that machine learning techniques so far have been under-exploited, and that a more proper standardization of the problem, also with regards to the underlying argument model, could provide a crucial element to develop better systems
Normality, Non-contamination and Logical Depth in Classical Natural Deduction
Get PDFIn this paper we provide a detailed proof-theoretical analysis of a natural deduction system for classical propositional logic that (i) represents classical proofs in a more natural way than standard Gentzen-style natural deduction, (ii) admits of a simple normalization procedure such that normal proofs enjoy the Weak Subformula Property, (iii) provides the means to prove a Non-contamination Property of normal proofs that is not satisfied by normal proofs in the Gentzen tradition and is useful for applications, especially in formal argumentation, (iv) naturally leads to defining a notion of depth of a proof, to the effect that, for every fixed natural k, normal k-depth deducibility is a tractable problem and converges to classical deducibility as k tends to infinity
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