This book provides a systematic analysis of many common argumentation schemes and a compendium of 96 schemes. The study of these schemes, or forms of argument that capture stereotypical patterns of human reasoning, is at the core of argumentation research. Surveying all aspects of argumentation schemes from the ground up, the book takes the reader from the elementary exposition in the first chapter to the latest state of the art in the research efforts to formalize and classify (...) the schemes, outlined in the last chapter. It provides a systematic and comprehensive account, with notation suitable for computational applications that increasingly make use of argumentation schemes. (shrink)

This book identifies 25 argumentation schemes for presumptive reasoning and matches a set of critical questions to each.

This book provides a systematic analysis of many common argumentation schemes and a compendium of 96 schemes. The study of these schemes, or forms of argument that capture stereotypical patterns of human reasoning, is at the core of argumentation research. Surveying all aspects of argumentation schemes from the ground up, the book takes the reader from the elementary exposition in the first chapter to the latest state of the art in the research efforts to formalize and classify (...) the schemes, outlined in the last chapter. It provides a systematic and comprehensive account, with notation suitable for computational applications that increasingly make use of argumentation schemes. (shrink)

Argumentation mining aims to automatically detect, classify and structure argumentation in text. Therefore, argumentation mining is an important part of a complete argumentation analyisis, i.e. understanding the content of serial arguments, their linguistic structure, the relationship between the preceding and following arguments, recognizing the underlying conceptual beliefs, and understanding within the comprehensive coherence of the specific topic. We present different methods to aid argumentation mining, starting with plain argumentation detection and moving forward to a (...) more structural analysis of the detected argumentation. Different state-of-the-art techniques on machine learning and context free grammars are applied to solve the challenges of argumentation mining. We also highlight fundamental questions found during our research and analyse different issues for future research on argumentation mining. (shrink)

Formal logic has often been seen as uniquely placed to analyze mathematical argumentation. While formal logic is certainly necessary for a complete understanding of mathematical practice, it is not sufficient. Important aspects of mathematical reasoning closely resemble patterns of reasoning in nonmathematical domains. Hence the tools developed to understand informal reasoning, collectively known as argumentation theory, are also applicable to much mathematical argumentation. This chapter investigates some of the details of that application. Consideration is given to the (...) many contrasting meanings of the word “argument”; to some of the specific argumentation-theoretic tools that have been applied to mathematics, notably Toulmin layouts and argumentation schemes; to some of the different ways that argumentation is implicated in mathematical practices; and to the social aspects of mathematical argumentation. (shrink)

I consider argumentation from the point of view of context-transcendent cognitive transformation through reference to the critical social theory of Jürgen Habermas. My aim is threefold. First, to make the case for a concept of context-transcendent cognitive transformation. Second, to clarify the transformatory role of argumentation itself by showing that, while argumentation may contribute constructively to context-transcendent cognitive transformation, such transformation presupposes the existence of a reality conceptually independent of argumentation. Third, to cast light on the (...) problem of how to justify argumentatively the poetically formulated, novel and innovative semantic contents that may be required for context-transcendent cognitive transformation. I conclude that the difficulties involved in argumentatively assessing novel and innovative semantic contents should not be misconstrued as evidence of an unbridgeable gap between language and experience but rather suggest the need for a more dynamic normative conception of language and for a more receptive model of autonomous agency. (shrink)

In this paper, it is explained that a dialogical approach to complex argumentation can be fruitful for solving two important problems concerning the analysis of the argumentation structure. First, such an approach makes it possible to clarify the distinction between coordinative and multiple argumentation structures, and to identify clues in the presentation for each of these structures. Second, a dialogical approach can provide a basis for dealing more adequately with refutations of counterarguments.

New pedagogical visions and technological developments have brought argumentation to the fore of educational practice. Whereas students previously 'learned to 'argue', they now 'argue to learn': collaborative argumentation-based learning has become a popular and valuable pedagogical technique, across a variety of tasks and disciplines. Researchers have explored the conditions under which arguing to learn is successful, have described some of its learning potentials and have developed Internet-based tools to support such learning. However, the further advancement of this field (...) presently faces several problems, which the present book addresses. Three dimensions of analysis - historical, theoretical and empirical - are integrated throughout the book. Given the nature of its object of study - dialogue, interaction, argumentation, learning and teaching - the book is resolutely multidisciplinary, drawing on research on learning in educational and psychological sciences, as well as on philosophical and linguistic theories of dialogue and argumentation. (shrink)

This paper is aimed at combining the advances in argumentation theory with the models used in the field of education to address the issue of improving students’ argumentative behavior by interacting with an expert. The concept of deeper or more sophisticated argumentative strategy is theoretically defined and used to advance two new coding schemes, based on the advances in the argumentation studies and aimed at capturing the dialectical, or structural, behavior, and the argumentative content of each dialogue unit. (...) These coding schemes are then applied for a qualitative analysis of a study designed to investigate how students’ argumentative behavior can be influenced by the interaction with an expert, who used specific types of attacks to the interlocutors’ positions. The twofold coding shows at which dialogical level expert–peer interactions can directly and more stably affect students’ argumentative behavior, and what effects such more sophisticated strategies can have on the discussion and the analysis of disagreements. In particular, this paper shows how a specific type of deep-level attack, the underminer, can open dialogues of a different level, focused on unveiling and debating background beliefs underlying a specific position. (shrink)

Prakken gives an argumentation‐based analysis of the manslaughter case using logical tools developed in AI. Prakken regards evidential argumentation as the construction and attack of ‘trees of inference’ from evidence to conclusions by applying generalizations. He argues that this approach clearly shows how evidence and hypotheses relate and what are the points of disagreement, but that it cannot give a clear overview over a case and lacks a systematic account of degrees of uncertainty.

In this paper we describe the impact that Walton’s conception of argumentation schemes had on AI and Law research. We will discuss developments in argumentation in AI and Law before Walton’s schemes became known in that community, and the issues that were current in that work. We will then show how Walton’s schemes provided a means of addressing all of those issues, and so supplied a unifying perspective from which to view argumentation in AI and Law.

The book offers a compact but comprehensive introductory overview of the crucial components of argumentation theory. In presenting this overview, argumentation is consistently approached from a pragma-dialectical perspective by viewing it pragmatically as a goal-directed communicative activity and dialectically as part of a regulated critical exchange aimed at resolving a difference of opinion. As a result, the book also systematically explains how the constitutive parts of the pragma-dialectical theory of argumentation, which are discussed in a number of (...) separate publications, hang together. The following crucial topics are discussed: argumentation theory as a discipline; the meta-theoretical principles of pragma-dialectics; the model of a critical discussion aimed at resolving a difference of opinion; fallacies as violations of a code of conduct for reasonable argumentative discourse; descriptive research of argumentative reality; analysis as theoretically-motivated reconstruction; strategic manoeuvring aimed at combining achieving effectiveness with maintaining reasonableness; the conventionalization of argumentative practices; prototypical argumentative patterns; pragma-dialectics amidst other approaches. Argumentation Theory: A Pragma-Dialectical Perspective is clearly written and makes argumentation theory understandable to all scholars and advanced students interested in argumentation research. (shrink)

The study presented here examines how interacting with a more capable interlocutor influences use of argumentation strategies in electronic discourse. To address this question, 54 young adolescents participating in an intervention centered on electronic peer dialogs were randomly assigned to either an experimental or control condition. In both conditions, pairs who held the same position on a social issue engaged in a series of electronic dialogs with pairs who held an opposing position. In the experimental condition, in some dialogs, (...) unbeknownst to them (because dialog took place electronically), the opponent was a more capable (“expert”) adult. Dialogs in the control condition were only with peers. Argumentation strategies of the experimental group who argued with the “expert” showed immediate strategy improvements in their subsequent peer dialogs, improvement absent in the control group (Cohen's d = 1.12). In particular, the experimental group showed greater use of counterargument in general and advanced forms of counterargument (undermining) that challenges the deeper premises or reasoning on which an argument is based. Implications with respect to mechanisms of change in the development of argumentation skills are considered. (shrink)

This paper demonstrates how argumentation schemes can be used in decision support systems that help clinicians in making treatment decisions. The work builds on the use of computational argumentation, a rigorous approach to reasoning with complex data that places strong emphasis on being able to justify and explain the decisions that are recommended. The main contribution of the paper is to present a novel set of specialised argumentation schemes that can be used in the context of a (...) clinical decision support system to assist in reasoning about what treatments to offer. These schemes provide a mechanism for capturing clinical reasoning in such a way that it can be handled by the formal reasoning mechanisms of formal argumentation. The paper describes how the integration between argumentation schemes and formal argumentation may be carried out, sketches how this is achieved by an implementation that we have created and illustrates the overall process on a small set of case studies. (shrink)

A "good" arguer is like an architect with a penchant for civil and civic engineering. Such an arguer can design and present their reasons artfully about a variety of topics, as good architects do with a plenitude of structures and in various environments. Failures in this are rarely hidden for long, as poor constructions reveal themselves, often spectacularly, so collaboration among civical engineers can be seen as a virtue. Our logical virtues should be analogous. When our arguments fail due to (...) being uncivil and demagogic, since we inhabit the arguments we build, we are all crushed beneath our flawed reasoning. This mixed metaphor takes us to a self-referential analysis of argumentation, analogy, and humor. I argue that good argumentation strives to collaboratively convince rather than belligerently persuade. A convincing means toward this end is through humorous analogical arguments, whether the matter at hand is ethical, logical, theological, phenomenological, epistemological, metaphysical, political, or about baseball. (shrink)

The detection of hate speech and fake news in political discourse is at the same time a crucial necessity for democratic societies and a challenge for several areas of study. However, most of the studies have focused on what is explicitly stated: false article information, language that expresses hatred, derogatory expressions. This paper argues that the explicit dimension of manipulation is only one – and the least problematic – of the risks of political discourse. The language of the unsaid is (...) much more dangerous and incomparably more difficult to detect, hidden in different types of fallacies and inappropriate uses of emotive language. Through a threefold coding scheme based on the instruments of argumentation theory and pragmatics, a corpus of argumentative tweets published by 4 politicians (Matteo Salvini, Donald Trump, Jair Bolsonaro, and Joseph Biden) within 6 months from their taking office (corresponding to the official end of their election campaign) is analyzed, detecting the types of argument, the fallacies, and the uses and misuses of “emotive words.” This coding results in the argumentation profiles of the speakers, which are compared statistically to show their different implicit strategies and deceptive tactics. (shrink)

The high prevalence of brain injury incidents in adolescence and adulthood demands effective models for re-learning lost cognitive abilities. Impairment in brain injury survivors’ higher-level cognitive functions is common and a negative predictor for long-term outcome. We conducted two small-scale interventions (N = 12; 33.33% female) with persons with acquired brain injuries in two municipalities in Sweden. Age ranged from 17 to 65 years (M = 51.17, SD = 14.53). The interventions were dialogic, inquiry-based, and inspired by the Philosophy for (...) Children Programme, a participatory thinking skills approach with documented higher-order cognitive outcomes, such as developed argumentation skills, in other target groups. Philosophical dialogues were conducted once a week in the two groups, totalling 12 dialogues per group. Group argumentation development was measured through compared scores from structured observations of filmed dialogues early and late in the intervention. Large positive changes in mean scores from early to late in the intervention, together with constantly high facilitator quality, suggest argumentation development in the sample due to the intervention. (shrink)

In this paper we provide a proof theoretical investigation of logical argumentation, where arguments are represented by sequents, conflicts between arguments are represented by sequent elimination rules, and deductions are made by dynamic proof systems extending standard sequent calculi. The idea is to imitate argumentative movements in which certain claims are introduced or withdrawn in the presence of counter-claims. This is done by a dynamic evaluation of sequences of sequents, in which the latter are considered ‘derived’ or ‘not derived’ (...) according to the content of the sequence. We show that decisive conclusions of such a process correspond to well-accepted consequences of the underlying argumentation framework. The outcome is therefore a general and modular proof-theoretical approach for paraconsistent and non-monotonic reasoning with argumentation systems. (shrink)

In this paper, we study conditional preferences in abstract argumentation by introducing a new generalization of Dung-style argumentation frameworks (AFs) called Conditional Preference-based AFs (CPAFs). Each subset of arguments in a CPAF can be associated with its own preference relation. This generalizes existing approaches for preference-handling in abstract argumentation, and allows us to reason about conditional preferences in a general way. We conduct a principle-based analysis of CPAFs and compare them to related generalizations of AFs. Specifically, we (...) highlight similarities and differences to Modgil’s Extended AFs and show that our formalism can capture Value-based AFs. Moreover, we show that in some cases the introduction of conditional preferences leads to an increase in computational complexity. (shrink)

In this paper we describe the impact that Walton’s conception of argumentation schemes had on AI and Law research. We will discuss developments in argumentation in AI and Law before Walton’s schemes became known in that community, and the issues that were current in that work. We will then show how Walton’s schemes provided a means of addressing all of those issues, and so supplied a unifying perspective from which to view argumentation in AI and Law.

"As a distinctive philosophy, religious humanism emphasizes man's place in an unfathomed universe, reason as an instrument for discovering the truth, free inquiry as a condition for discerning meaning and purpose, and happiness as a fundamental value. "Man's uniqueness emerges partly from homo sapiens' capacity to employ symbols effectively. For this reason, Willard's provocative book is not a celebration of controversy but a sophisticated study exploring the grounds of man's knowledge. Drawing upon phenomenologists such as Alfred Schultz, psychologists such as (...) George Kelley, and argumentation philosophers such as Stephen Toulmin, Willard makes a genuine contribution to intellectual inquiry by extending essential consideration about human knowledge. The [author] demonstrates how 'secular sources' provide a fundamental resource in developing religious understanding from argumentative interactions. "Highly insightful and intellectually refreshing... _Argumentation and the Social Grounds of Knowledge_ provides thought-provoking reading for humanists concerned with rational inquiry, communication theory, religious philosophy, and liberal education." _--Religious Humanism_. (shrink)

This essay begins with a critique of the Critical-Logical model dominant in contemporary argumentation theory. The concerns raised stem primarily from considerations brought by several feminist thinkers including Carol Gilligan, Karen Warren, Deborah Tannen and, most especially, Andrea Nye. It is argued that, in light of these considerations, and concerns of essentialism or non-essentialism notwithstanding, that the Critical-Logical model is liable to dis-enfranchise a significant part of the population with regard to modes and styles of reasoning. The solution is (...) found in coalescent reasoning, an approach to argumentation that focuses on finding agreement rather than emphasizing disagreement and criticism. (shrink)

This book concentrates on argumentation as it emerges in ordinary discourse, whether the discourse is institutionalized or strictly informal. Crucial concepts from the theory of argumentation are systematically discussed and explained with the help of examples from real-life discourse and texts. The basic principles are explained that are instrumental in the analysis and evaluation of argumentative discourse. Methodical instruments are offered for identifying differences of opinion, analyzing and evaluating argumentation and presenting arguments in oral and written discourse. (...) In addition, the book provides a great variety of exercises and assignments to improve the students' skill in presenting argumentation. The authors begin their treatment of argumentation theory at the same juncture where argumentation also starts in practice: The difference of opinion that occasions the evolvement of the argumentation. Each chapter begins with a short summary of the essentials and ends with a number of exercises that students can use to master the material. _Argumentation_ is the first introductory textbook of this kind. It is intended as a general introduction for students who are interested in a proper conduct of argumentative discourse. Suggestions for further reading are made for each topic and several extra assignments are added to the exercises. Special features: * A concise and complete treatment of both the theoretical backgrounds and the practice of argumentation analysis and evaluation. * Crucial concepts from pragmatics presented in a non-technical way; introducing the theory of verbal communication. * Unique coverage of both oral and written presentation of arguments. * Exercises and assignments based on real-life texts from a variety of contexts. (shrink)

A leading expert in informal logic, Douglas Walton turns his attention in this new book to how reasoning operates in trials and other legal contexts, with special emphasis on the law of evidence. The new model he develops, drawing on methods of argumentation theory that are gaining wide acceptance in computing fields like artificial intelligence, can be used to identify, analyze, and evaluate specific types of legal argument. In contrast with approaches that rely on deductive and inductive logic and (...) rule out many common types of argument as fallacious, Walton’s aim is to provide a more expansive view of what can be considered "reasonable" in legal argument when it is construed as a dynamic, rule-governed, and goal-directed conversation. This dialogical model gives new meaning to the key notions of relevance and probative weight, with the latter analyzed in terms of pragmatic criteria for what constitutes plausible evidence rather than truth. (shrink)

We present a new framework for combining logic with probability, and demonstrate the application of this framework to breast cancer prognosis. Background knowledge concerning breast cancer prognosis is represented using logical arguments. This background knowledge and a database are used to build a Bayesian net that captures the probabilistic relationships amongst the variables. Causal hypotheses gleaned from the Bayesian net in turn generate new arguments. The Bayesian net can be queried to help decide when one argument attacks another. The Bayesian (...) net is used to perform the prognosis, while the argumentation framework is used to provide a qualitative explanation of the prognosis. (shrink)

A broad assumption in argumentation theory is that argumentation primarily regards resolving, confronting, or managing disagreement. This assumption is so fundamental that even when there does not appear to be any real disagreement, the disagreement is suggested to be present at some other level. Some have questioned this assumption (most prominently, Perelman and Olbrechts-Tyteca, and Doury), but most are reluctant to give up on the key idea that persuasion, the core of argumentation theory, can only regard disagreements. (...) We argue here that this assumption is false. Argument may be as much about strengthening or maintaining agreement as it is about disagreement. Once we see how argument is possible and manifestly enacted under conditions of agreement, then we have tools to explain otherwise curious fallacies and argumentative phenomena. (shrink)

Various argumentation analysis tools permit the analyst to represent functional components of an argument (e.g., data, claim, warrant, backing), how arguments are composed of subarguments and defenses against potential counterarguments, and argumentation schemes. In order to facilitate a study of argument presentation in a biomedical corpus, we have developed a hybrid scheme that enables an analyst to encode argumentation analysis within the framework of Rhetorical Structure Theory (RST), which can be used to represent the discourse structure of (...) a text. This paper describes the hybrid representation scheme and illustrates its use for investigation of contexts that license omission of elements of an argument. The analyses given in the paper involve reconstruction of enthymemes. Defeasible argumentation schemes serve as a constraint on reconstruction. In addition, the examples illustrate several other types of contextual constraints on reconstruction of enthymemes. (shrink)

This paper presents the past and present efforts of developing real-life applications of argumentation with the Gorgias preference-based structured argumentation framework of Logic Programming with Priorities. Since its free availability on the web in 2003, the Gorgias system has been used by different groups in a variety of real-life applications in areas such as medical support, network security, business computing, ambient intelligence and, recently, in the area of cognitive personal assistants. We briefly review the Gorgias framework and its (...) past applications and present an emerging general methodological approach for developing “decision making” applications of argumentation. This approach allows the development of real world applications directly from their high-level requirements expressed in the language of the application without the need for familiarity with the underlying technical details of argumentation. A new tool, called Gorgias-B, supports this high-level development of applications and automatically generates the underlying argumentation theory in Gorgias code. The paper also reports on ongoing real-life applications in two domains: an eye-clinic assistant for first level support, and systems for patient data access and data sharing agreements according to the relevant legislation and contracts or policies of the several stakeholders involved. The proposed approach is quite general for this type of applications of argumentation and, thus, it can be used with any preference-based argumentation framework. (shrink)

This book analyzes the uses of emotive language and redefinitions from pragmatic, dialectical, epistemic and rhetorical perspectives, investigating the relationship between emotions, persuasion and meaning, and focusing on the implicit dimension of the use of a word and its dialectical effects. It offers a method for evaluating the persuasive and manipulative uses of emotive language in ordinary and political discourse. Through the analysis of political speeches and legal arguments, the book offers a systematic study of emotive language in argumentation, (...) rhetoric, communication, political science and public speaking. (shrink)

We present a high-level declarative programming language for representing argumentation schemes, where schemes represented in this language can be easily validated by domain experts, including developers of argumentation schemes in informal logic and philosophy, and serve as executable specifications for automatically constructing arguments, when applied to a set of assumptions. Since argumentation schemes are defeasible inference rules, both premises and conclusions of schemes can be second-order schema variables, i.e. without a fixed predicate symbol. Thus, while particular schemes (...) can be and have been implemented in computer programs, in general argumentation schemes cannot be represented as executable specifications using logic programming languages based on first-order logic, such as Prolog. Moreover, even if the conclusion (head) of Prolog rules could be second-order variables, a depth-first, backward-chaining search strategy, as typically used in logic programming, would usually cause such programs to not terminate, since every goal would match the head of such a scheme, including all goals created by instantiating the body of the same scheme. The language for representing argumentation schemes presented here, for the purpose of automatically constructing arguments, uses Constraint Handling Rules (CHR), a declarative, Turing complete, forwards-chaining, rule-based programming language introduced by Thom Frühwirth in 1991. CHR is attractive for representing and implementing argumentation for several reasons, including: 1) Inference rules, rewrite rules, sequents, proof rules, and logical axioms can be directly written in CHR. 2) The execution of CHR rules can be interrupted and restarted at any time, with intermediate results approximating the final solution, and 3) Constraints can be input incrementally as they become known, during rule execution, without requiring recomputation. These three properties of CHR appear attractive for representing and implementing argumentation schemes. Since argumentation schemes are (defeasible) inference rules, the ability of CHR to represent inference rules directly would appear to be quite useful. The ability to stop the computation and produce approximate results is compatible with one objective of argumentation, to provide a principled method for supporting approximate reasoning with limited resources. Because argumentation typically takes place in dialogs, with evidence and arguments brought forward and asserted by the participants incrementally, during the course of the dialog, CHR’s ability to handle new information, incrementally introduced during the computation, may be useful. This new rule language for representing argumentation schemes is validated by using it to represent twenty representative argumentation schemes. (shrink)

This paper presents a comprehensive study of argumentation frameworks with necessities (AFNs), a bipolar extension of Dung Abstract argumentation frameworks (AFs) where the support relation captures a positive interaction between arguments having the meaning of necessity: the acceptance of an argument may require the acceptance of other argument(s). The paper discusses new main acceptability semantics for AFNs and their characterization both by a direct approach and a labelling approach. It examines the relationship between AFNs and Dung AFs and (...) shows the gain provided by the former in terms of concision. Finally, the paper shows how to represent an AFN as a normal logic program (LP) and vice versa and in both cases establishes a one-to-one correspondence between extensions under the main acceptability semantics (except for semi-stable semantics where the correspondence is not completely full) of an AFN and particular cases of 3-valued stable models of normal LPs. (shrink)

In this paper, I review and compare major literature on goals in argumentation scholarship, aiming to answer the question of how to take the different goals of arguers into account when analysing and evaluating public political arguments. On the basis of the review, I suggest to differentiate between the different goals along two important distinctions: first, distinguish between goals which are intrinsic to argumentation and goals which are extrinsic to it and second distinguish between goals of the act (...) of arguing and goals of argumentative interactions. Furthermore, I propose to analyse public political arguments as multi-purposive activity types and reconstruct the argumentative exchanges as a series of simultaneous discussions. This enables us to examine public political arguments from a perspective in which the intrinsic goals of argumentation are in principle instrumental for the achievement of the socio-political purposes of argumentation, and consequently, it makes our assessment of the argumentative quality of the argument also indicative of the quality of the socio-political processes to which the arguments contribute. (shrink)

Rather than the art of putting forward logically valid arguments leading to Truth, argumentation is here viewed as the use of verbal means ensuring an agreement on what can be considered reasonable by a given group, on a more or less controversial matter. What is acceptable and plausible is always coconstructed by subjects engaging in verbal interaction. It is the dynamism of this exchange, realized not only in natural language, but also in a specific cultural framework, that has to (...) be accounted for. From this perspective, it is not enough to reconstruct patterns of reasoning. As logos is by definition both Reason and Language, abstract schemata have to be examined in their verbal realization in a given situation of discourse. Such an approach to arguments allows for a “thick” description taking into account their discursive and communicational aspects, as well as argumentation’s constitutive dialogism and its inscription in a set of common representations, opinions and beliefs (a doxa). This approach, exemplified by the analysis of a short text on stock options borrowed from the French newspaper Libération, is an attempt at establishing a dialogue between disciplines like argumentation theories, rhetorical criticism and discourse analysis. (shrink)

We present a computational model of dialectical argumentation that could serve as a basis for legal reasoning. The legal domain is an instance of a domain in which knowledge is incomplete, uncertain, and inconsistent. Argumentation is well suited for reasoning in such weak theory domains. We model argument both as information structure, i.e., argument units connecting claims with supporting data, and as dialectical process, i.e., an alternating series of moves by opposing sides. Our model includes burden of proof (...) as a key element, indicating what level of support must be achieved by one side to win the argument. Burden of proof acts as move filter, turntaking mechanism, and termination criterion, eventually determining the winner of an argument. Our model has been implemented in a computer program. We demonstrate the model by considering program output for two examples previously discussed in the artificial intelligence and legal reasoning literature. (shrink)

In this contribution, I will develop a comprehensive tool for the reconstruction and evaluation of argumentation from expert opinion. This is done by analyzing and then combining two dialectical accounts of this type of argumentation. Walton’s account of the ‘appeal to expert opinion’ provides a number of useful, but fairly unsystematic suggestions for critical questions pertaining to argumentation from expert opinion. The pragma-dialectical account of ‘argumentation from authority’ offers a clear and systematic, but fairly general framework (...) for the reconstruction and evaluation of this type of argumentation. The tool is developed by incorporating Walton’s critical questions into a pragma-dialectical framework. (shrink)

According to the Bayesian paradigm in the psychology of reasoning, the norms by which everyday human cognition is best evaluated are probabilistic rather than logical in character. Recently, the Bayesian paradigm has been applied to the domain of argumentation, where the fundamental norms are traditionally assumed to be logical. Here, we present a major generalisation of extant Bayesian approaches to argumentation that (i)utilizes a new class of Bayesian learning methods that are better suited to modelling dynamic and conditional (...) inferences than standard Bayesian conditionalization, (ii) is able to characterise the special value of logically valid argument schemes in uncertain reasoning contexts, (iii) greatly extends the range of inferences and argumentative phenomena that can be adequately described in a Bayesian framework, and (iv) undermines some influential theoretical motivations for dual function models of human cognition. We conclude that the probabilistic norms given by the Bayesian approach to rationality are not necessarily at odds with the norms given by classical logic. Rather, the Bayesian theory of argumentation can be seen as justifying and enriching the argumentative norms of classical logic. (shrink)