This paper uses argument diagrams, argumentation schemes, and some tools from formal argumentation systems developed in artificial intelligence to build a graph-theoretic model of relevance shown to be applicable as a practical method for helping a third party judge issues of relevance or irrelevance of an argument in real examples. Examples used to illustrate how the method works are drawn from disputes about relevance in natural language discourse, including a criminal trial and a parliamentary debate.

The research discussed in this paper concerns an investigation of logical dialogue games as a vehicle for enhanced human-computer communication. The need for a dialogue capability in computer systems is argued, and a prima facie case made for dialogue games, in particular Mackenzie's "DC", as a suitable dialogue model. Empirical work concerning DC is outlined, and strategies for adoption by the computer are presented. A user interface, software architecture and conceptualised example are discussed. The hope is that the paper will (...) help bring together two groups of workers-philosophers of dialogue and designers of computer systems-to the mutual benefit of each. (shrink)

The article discusses burden of proof rules in social criticism. By social criticism I mean an argumentative situation in which an opponent publicly argues against certain social practices; the examples I consider are discrimination on the basis of species and discrimination on the basis of one's nationality. I argue that burden of proof rules assumed by those who defend discrimination are somewhat dubious. In social criticism, there are no shared values which would uncontroversially determine what is the reasonable presumption and (...) who has the burden of proof, nor are there formal rules which would end the debate and determine the winner at a specific point. (shrink)

Questions, and more specifically authentic questions, are at the core of dialogue-based learning and teaching. However, what is a question, and how can it be authentic? This paper addresses this problem by analyzing the distinct dimensions of questions, showing how their pragmatic nature is interwoven with the syntactic and semantic one, and how it can be grasped only by considering their dialogical functions. Questions are maintained to be proposals of different dialogue games (or types), pursuing specific interactional purposes, and potentially (...) contributing to learning processes in different ways. By understanding how questions shape different dialogues it is possible to ask more suitable questions to the questioner’s goals. In this framework, the dichotomy between authentic and inauthentic questions becomes a strategic choice between different types of dialogical possibilities. (shrink)

This paper advances an approach to relevance grounded on patterns of material inference called argumentation schemes, which can account for the reconstruction and the evaluation of relevance relations. In order to account for relevance in different types of dialogical contexts, pursuing also non-cognitive goals, and measuring the scalar strength of relevance, communicative acts are conceived as dialogue moves, whose coherence with the previous ones or the context is represented as the conclusion of steps of material inferences. Such inferences are described (...) using argumentation schemes and are evaluated by considering 1) their defeasibility, and 2) the acceptability of the implicit premises on which they are based. The assessment of both the relevance of an utterance and the strength thereof depends on the evaluation of three interrelated factors: 1) number of inferential steps required; 2) the types of argumentation schemes involved; and 3) the implicit premises required. (shrink)

This paper has three dimensions, historical, theoretical and social. The historical dimension is to show how the Ciceronian system of dialectical argumentation served as a precursor to computational models of argumentation schemes such as Araucaria and Carneades. The theoretical dimension is to show concretely how these argumentation schemes reveal the interdependency of rhetoric and logic, and so the interdependency of the normative with the empirical. It does this by identifying points of disagreement in a dialectical format through using argumentation schemes (...) and critical questions. The social dimension is to show how the Ciceronian dialectical viewpoint integrates with the use of computational tools that can be used to support the principle of reason-based deliberation and facilitate deliberative democracy. (shrink)

The traditional fallacy of many questions, also known as the fallacy of complex question, illustrated by the question, "Have you stopped sexually harassing your students?", has been known since ancient times, but is still alive and well. What is of practical importance about this fallacy is that it represents a tactic of entrapment that is very common in everyday argumentation, as well as in special kinds of argumentation like that in a legal trial or a parliamentary debate. The tactic combines (...) the use of loaded questions with the complexity of the question. A key notion is that of the presupposition of the question. How to deal with such questions is a point of departure for interrogative theory, and for any attempts to construct formal dialogues of a kind that can be used as normative models of argumentation. (shrink)

Both questions as abstract objects and the speech acts, here called requests, by which we ask them play an enormous role in all argumentative practices. Nonetheless, there is hardly a proper systematic treatment of questions and requests in current argumentation theories. This paper is a first attempt at providing such a systematic treatment. This is achieved by following the ideal model of a critical discussion as elaborated over the years by the Amsterdam school of pragma-dialectics. After introducing the distinction between (...) questions and requests, the paper sets forth and illustrates the norms of questioning which implicitly underlie the four stages of a critical discussion in the standard order: confrontation, opening, argumentation, and conclusion. Among other things, it is shown that crucial insights of pragma-dialectics are illuminated by the questioning perspective, in particular the distinction between single and multiple differences of opinion, the duties of the antagonist and protagonist roles, the precise character of the argumentation stage, and the different ways in which a disagreement can be resolved. (shrink)

This volume presents a selection of papers reflecting key theoretical issues in argumentation theory. Its six sections are devoted to specific themes, including the analysis and evaluation of argumentation, argument schemes and the contextual embedding of argumentation. The section on general perspectives on argumentation discusses the trends of empiricalization, contextualization and formalization, offers descriptions of the analytical and evaluative tools of informal logic, and highlights selected principles that argumentation theorists do and do not agree upon. In turn, the section on (...) linguistic approaches to argumentation focuses on the problem of distinguishing between explanation and argument, while also elaborating on the role of verbal indicators of argument schemes. All essays included in this volume point out notable recent developments in the study of argumentation. (shrink)

The standard account of denying the antecedent (DA) is that it is a deductively invalid form of argument, and that, in a conditional argument, to argue from the falsity of the antecedent to the falsity of the consequent is always fallacious. In this paper, we argue that DA is not always a fallacious argumentative strategy. Instead, there is a legitimate usage of DA according to which it is a defeasible argument against the acceptability of a claim. The dialectical effect of (...) denying the antecedent is to shift the burden of proof back to the original proponent of a claim. We provide a model of this non-fallacious usage which is built upon pragmatic models of argumentation. (shrink)

In many contexts a retraction of commitment isfrowned upon. For instance, it is not appreciated,generally, if one withdraws a promise or denies anearlier statement. Critical discussion, too, caneasily be disrupted by retractions, if these occur toofrequently and at critical points. But on the otherhand, the very goal of critical discussion –resolution of a dispute – involves a retraction,either of doubt, or of some expressed point of view.A person who never retracts, not even under pressureof cogent arguments, would hardly qualify as (...) areasonable discussant. Also, inconsistencies in one'sposition, once they have been pointed out, must bedealt with by some kind of retraction. The problem ofretraction is to find a suitable model of dialoguethat allows retractions where they seem reasonable, oreven required, and rules them out (or puts sanctionsupon them) whenever they would become disruptive of awell-organized process of dialogue.The present paper tries to point to a solution basedon the following principles: (1) Retraction rulesdetermine what retractions are permissible, and (2) ifpermissible what the consequences of retraction are.(3) Retraction rules vary according to the type ofdialogue and (4) according to the type of commitmentretracted. For instance, assertions and mereconcessions need to be distinguished, as well aslight-side and dark-side commitments. (5) To accountfor our contradictory intuitions on the issue ofretractions, one may best resort to a complex type ofdialogue in which different retraction rules hold fordifferent parts.The paper explains, summarizes, and expands upon thediscussion of retraction in Commitment inDialogue by Douglas Walton and the present author(cf. Walton and Krabbe 1995). (shrink)

How do Dutch people let each other know that they disagree? What do they say when they want to resolve their difference of opinion by way of an argumentative discussion? In what way do they convey that they are convinced by each other’s argumentation? How do they criticize each other’s argumentative moves? Which words and expressions do they use in these endeavors? By answering these questions this short essay provides a brief inventory of the language of argumentation in Dutch.

Amphiboly has been widely recognized, starting from the time of Aristotle, as an informal fallacy arising from grammatical ambiguity. This paper applies the profiles of dialogue tool to the fallacy of amphiboly, providing a five-step evidence-based procedure whereby a syntactically ambiguous sentence uttered in a natural language text can be evaluated as committing a fallacy of amphiboly. A user applies the tool to a natural language text by comparing a descriptive graph, representing how the argumentation actually went, to a normative (...) graph, representing how the argumentation should ideally have proceeded. (shrink)

A simple way to approach fallacies is to ask, "Has reasoning-strategy X retarded or halted the growth of knowledge?" and seek uncontroversial historical events as empirical support for the fallacy moniker. Historical support also offers a means of retiring reasoning strategies heretofore thought fallacious—they are wrongly accused if they helped drive knowledge. Finally, this approach allows us to be more critical of our argumentative practices. Evidence is offered for an Intuitive Fallacy: In its extreme form it rules out the possibility (...) of evidence; in its weaker form, it is a non-response to evidence that appears to be a response. (shrink)

In this paper the authors give a brief overview of the theoretical background of their research project “Linguistic indicators of argumentative moves.” Starting from the pragma-dialectical ideal model of a critical discussion, they design dialectical profiles for capturing the moves that may or must be made at a particular stage or sub-stage of such a discussion. They explain how these dialectical profiles can be methodically exploited for systematically identifying the verbal expressions that can be indicative of any of these moves (...) in argumentative practice. (shrink)

“Reasonable hostility” is a norm of communicative conduct initially developed by studying public exchanges in education governance meetings in local U.S. communities. In this paper I consider the norm’s usefulness for and applicability to a U.S. state-level public hearing about a bill to legalize civil unions. Following an explication of reasonable hostility and grounded practical theory, the approach to inquiry that guides my work, I de-scribe Hawaii’s 2009, 18-hour pub-lic hearing and analyze selected segments of it. I show that this (...) par-ticular public hearing raised de-mands for testifiers on the anti-civil union side of the argument that rea-sonable hostility does not do a good job of addressing. Development of a norm of communication conduct for this practice, as well as others, must engage with the culture and time-specific beliefs that a society holds, beliefs that will shape not only how to argue but what may be argued and what must be assumed about particular categories of persons. (shrink)

This paper discusses several types of relevance criticism within dialogue. Relevance criticism is a way one could or should criticize one's partner's contribution in a conversation as being deficient in respect of conversational coherence. The first section tries to narrow down the scope of the subject to manageable proportions. Attention is given to the distinction between criticism of alleged fallacies within dialogue and such criticism as pertains to argumentative texts. Within dialogue one may distigguish tenability criticism, connection criticism, and narrow-type (...) relevance criticism. Only the last of these three types of criticism constitutes a charge of fallacy and carries with it a burden of proof. In the second it is observed that a full study of narrow-type relevance criticism would require the construction of complicated, many-layered, dialogue systems. Such a study can, however, be profitably preceded by setting up profiles of dialogue that help us discuss the ins and outs of certain types of move. This is illustrated with an example. (shrink)

The question of who has the burden of proof is often important in practice. We must frequently make decisions and act on the basis not of conclusive evidence but of what is reasonable to presume true. Consequently, it happens that a given practical question must be solved by referring to principles that explicitly or implicitly determine, at least partly, where the burden of proof should rest. In this essay, I consider the role of the logic of the burden of proof (...) in a debate on global justice. In particular, I ask how the logic of the burden of proof is seen by those who defend conservative positions in a debate and deny our obligations to reduce poverty beyond borders. I argue that defenders of conservative positions tend to shift the burden of proof in an unjustified way. (shrink)

Dialogue theory, although it has ancient roots, was put forward in the 1970s in logic as astructure that can be useful for helping to evaluate argumentation and informal fallacies.Recently, however, it has been taken up as a broader subject of investigation in computerscience. This paper surveys both the historical and philosophical background of dialoguetheory and the latest research initiatives on dialogue theory in computer science. The main components of dialogue theory are briefly explained. Included is a classification of the main (...) types of dialogue that, it is argued, should provide the central focus for studying many important dialogue contexts in specific cases. Following these three surveys, a concluding prediction is made about the direction dialogue theory is likely to take in the next century, especially in relation to the growing field of communication studies. (shrink)

This paper reports research concerning a suitable dialogue model for human computer debate. In particular, we consider the adoption of Moore's (1993) utilization of Mackenzie's (1979) game DC, means of using computational agents as the test-bed to facilitate evaluation of the proposed model, and means of using the evaluation results as motivation to further develop a dialogue model, which can prevent fallacious argument and common errors. It is anticipated that this work will contribute toward the development of human computer dialogue, (...) and help to illuminate research issues in the field of dialectics itself. (shrink)

This investigation uses the technique of the profile of dialogue as a tool for the evaluation of arguments from ignorance (also called lack-of-evidence arguments, negative evidence, ad ignorantiam arguments and ex silentio arguments). Such arguments have traditionally been classified as fallacies by the logic textbooks, but recent research has shown that in many cases they can be used reasonably. A profile of dialogue is a connected sequence of moves and countermoves in a conversational exchange of a type that is goal-directed (...) and can be represented in a normative model of dialogue. Selected case studies are used to probe special features of using the profile technique as applied to arguments from ignorance of a kind that occur frequently in everyday conversational exchanges. One of these special features is the use of Gricean implicature. Another is the need to use negative profiles of argument. (shrink)

The purpose of this paper is to discuss some ways in which dialectical models can be put to computational use. In particular, we consider means of facilitating human-computer debate, means of catering for a wider range of dialogue types than purely debate and means of providing dialectical support for group dialogues. We also suggest how the computational use of dialectical theories may help to illuminate research issues in the field of dialectic itself.

In this paper I focus on the fallacy known as Complex Question or Many Questions. After a brief introduction, in Sect. 2 I highlight its pragmatic dimension, and in Sect. 3 its dialectical dimension. In Sect. 4 I present two accounts of this fallacy developed in argumentation theory, Douglas Walton’s and the Pragma-Dialectics’, which have resources to capture both its pragmatic and its dialectical nature. However, these accounts are unsatisfactory for various reasons. In Sect. 5 I focus on the pragmatic (...) dimension of the fallacy and I suggest amendments to the accounts mentioned drawing on the study of the phenomenon of presupposition in theoretical pragmatics. I argue that the central notion in the definition of the fallacy is that of an informative presupposition. In Sect. 6 I focus on the dialectical dimension of the fallacy. This dimension needs to be explicitly acknowledged in the definition of the fallacy in order to distinguish it from a different, non-dialectical, fallacious argumentative move involving presuppositions. (shrink)

This paper reports our research concerning dialogue strategies suitable for adoption by a human-computer debating system. We propose a set of strategic heuristics for a computer to adopt to enable it to function as a dialogue participant. In particular, we consider means of assessing the proposed strategy. A system involving two agents in dialogue with each other and a human-agent debate system are constructed and subsequently used to facilitate the evaluations. The evaluations suggest that the proposed strategy can enable the (...) computer to act as an effective dialogue participant. It is anticipated that this work will contribute towards the development of computerised dialogue systems and help to illuminate research issues concerning strategies in dialectical systems. (shrink)

In a published exchange, Richard Robinson and Roy A. Sorenson debate the matter of whether begging the question is a fallacy; Robinson thinks it is not, but Sorenson argues that it is. Norman Ten attempts to resolve this debate by making a distinction between begging the question and fallaciously begging the question. While Teng is right to note that Robinson and Sorenson are talking past each other, he incorrectly diagnoses the source of this miscommunication. In this paper, then, I offer (...) what I take to be a more illuminating distinction 3; viz. that between logical and rhetorical fallacies 3; and employ that distinction to resolve the debate. (shrink)