This monograph poses a series of key problems of evidential reasoning and argumentation. It then offers solutions achieved by applying recently developed computational models of argumentation made available in artificial intelligence. Each problem is posed in such a way that the solution is easily understood. The book progresses from confronting these problems and offering solutions to them, building a useful general method for evaluating arguments along the way. It provides a hands-on survey explaining to the reader how to use current (...) argumentation methods and concepts that are increasingly being implemented in more precise ways for the application of software tools in computational argumentation systems. It shows how the use of these tools and methods requires a new approach to the concepts of knowledge and explanation suitable for diverse settings, such as issues of public safety and health, debate, legal argumentation, forensic evidence, science education, and the use of expert opinion evidence in personal and public deliberations. (shrink)

The public is largely innumerate, making systematic mistakes in estimating some politically relevant facts, such as the share of foreign-born citizens. In two-step or multistep flow models, such mistakes could be corrected if better-informed citizens were able to convince their peers, in particular by using good arguments citing reliable sources. In six experiments, we find two issues that dampen the potential power of this two-step flow process. First, even though participants were more convinced by good than by poor arguments, many (...) did not change their minds, even when confronted with good arguments. Second, participants are not inclined to spontaneously generate arguments that cite reliable sources, even when they have just been influenced by such arguments. Both issues should put a significant brake in the spread of political numeracy through the two-step flow process, in particular in non-dialogic contexts. (shrink)

Argument evaluation, one of the central problems in argumentation theory, consists in studying what makes an argument a good one. This paper proposes a formal approach to argument evaluation from the perspective of justification logic. We adopt a multi-agent setting, accepting the intuitive idea that arguments are always evaluated by someone. Two general restrictions are imposed on our analysis: non-deductive arguments are left out and the goal of argument evaluation is fixed: supporting a (...) given proposition. Methodologically, our approach uses several existing tools borrowed from justification logic, awareness logic, doxastic logic and logics for belief dependence. We start by introducing a basic logic for argument evaluation, where a list of argumentative and doxastic notions can be expressed. Later on, we discuss how to capture the mentioned form of argument evaluation by defining a preference operator in the object language. The intuitive picture behind this definition is that, when assessing a couple of arguments, the agent puts them to a test consisting of several criteria. As a result of this process, a preference relation among the evaluated arguments is established by the agent. After showing that this operator suffers a special form of logical omniscience, called preferential omniscience, we discuss how to define an explicit version of it, more suitable to deal with non-ideal agents. The present work exploits the formal notion of awareness in order to model several informal phenomena: awareness of sentences, availability of arguments and communication between agents and external sources. We discuss several extensions of the basic logic and offer completeness and decidability results for all of them. (shrink)

The virtues and vices of argument are now an established part of argumentation theory. They have helped direct attention to hitherto neglected aspects of how we argue. However, it remains controversial whether a virtue theory can contribute to some of the central questions of argumentation theory. Notably, Harvey Siegel disputes whether what he calls ‘arguments in the abstract propositional sense’ can be evaluated meaningfully within a virtue theory. This paper explores the prospects for grounding an account of argument (...) evaluation in arguers’ virtues and vices by examination of a corresponding debate in virtue ethics: Can an ethics of virtue guide our actions? It is thereby argued that an affirmative answer is possible: virtues suffice for argument evaluation. (shrink)

The "myside bias'' in evaluating arguments is an empirically well-confirmed phenomenon that consists of overweighting arguments that endorse one's beliefs or attack alternative beliefs while underweighting arguments that attack one's beliefs or defend alternative beliefs. This paper makes two contributions: First, it proposes a probabilistic model that adequately captures three salient features of myside bias in argument evaluation. Second, it provides a Bayesian justification of this model, thus showing that myside bias has a rational Bayesian explanation under certain (...) conditions. (shrink)

One of the greatest challenges in teaching an introductory philosophy course is convincing students that there are, indeed, reliable standards for the evaluation of arguments. Too often introductory students criticize an argument simply by contesting the truth of one of its claims. And far too often, the only claim in an argument that meets serious objections is its conclusion. For many students, the idea that an argument displays a structure which can be evaluated on its own (...) terms is not very difficult to grasp. Unfortunately, the idea is grasped only in an abstract way, with insufficient appreciation of how structural problems manifest themselves in concrete arguments, and without the vocabulary for formulating structural criticisms. But this paper is not simply about teaching logic, it is about pedagogy. Our task is to instill in the student the habit of clear thinking. When we send our students out into the world, we have to ensure that they are prepared for it. (shrink)

In Vol. XI, No.1, this journal announced an argument analysis contest. Two eminent colleagues agreed to serve as judges-Professor Henry W. Johnstone, Jr. and Professor Michael Scriven. In short order, four entries were received and sent off to the judges, who had no knowledge of the contestants' identities, and in due course the judges' verdicts were delivered. Immediately below we have reproduced the argument which was to be analyzed, along with the rules of the contest, followed by the (...) four entries. Thereafter we present the judges' rulings. (shrink)

The main thesis underlying the methodological approach to argument evaluation holds that some arguments which employ knowledge-gaining procedures can be suc-cessfully evaluated by applying tools elaborated by the methodology of science, such as the rules for reasoning, classifying objects, defining, and questioning. The applica-tion of those rules to argument evaluation consists in comparing them with proce-dures employed in the case of argumentative practices performed either in scientific inquiry or in everyday life. In order to show how (...) building the methodological ap-proach to argument evaluation could be started, I examine two cases of evaluating arguments by means of several methodological rules of defining. The idea of apply-ing the rules governing various knowledge-gaining procedures to evaluating argu-ments is present in philosophy of science and in argumentation theory, but so far it has not been systematically elaborated. The paper aims at justifying this idea as a promising research project. (shrink)

The aim of this paper is to defend the claim that arguments are truth-directed, and to discuss the role that truth plays in the evaluation of arguments that are truth-directed. It concludes that the proper place of truth is in the metatheory in terms of which a theory of evaluation is to be worked out, rather than in the theory of evaluation itself as a constraint on premise adequacy.

An argument evaluation inventory distinguishing between different levels of theory-evidence differentiation was designed corresponding to the levels of argument observed in argument generation tasks. Five scenarios containing everyday theories about a social problem, and arguments to support those theories were presented to 170 participants from two age groups (15 and 22 years) and different educational tracks. Participants had to rate the validity of arguments proposed by a story figure, to support the theory, to choose the best (...) argument, and to justify their choice. The rating task proved to be very difficult for all age groups, with only 49% of the university students consistently rating valid evidence-based arguments higher than flawed arguments. Competence improved with age and educational level. In the choice task more than 80% of the adults preferred an argument that reflected theory-evidence differentiation over mere theory elaboration or flawed reasoning. However, only adults with a university education were able to also explicitly justify their choice. Overall, these findings imply that laypersons have similar conceptual problems in differentiating theory from evidence as it has been reported for evidence generation tasks (Kuhn, 1991). Performance on the choice task suggests that some implicit awareness of differences between theory and evidence may precede a full, explicit understanding. Implications for education are discussed. (shrink)

This paper discusses virtue argumentation theory, as modeled on virtue epistemology. It argues that virtues of argumentation are interesting but parasitic on a more fundamental account of what makes arguments good. -/- *Note: this is an unpublished manuscript presented at the 2013 conference of the Ontario Society for the Study of Argumentation. An electronic copy is available in the Conference Archive, linked above.

According to the argument scheme approach, to evaluate a given scheme-saturating instance completely does entail asking all critical questions relevant to it. Although this is a central task for argumentation theorists, the field currently lacks a method for providing a complete argument evaluation. Approaching this task at the meta-level, we combine a logical with a substantive approach to the argument schemes by starting from Toulmin’s schema: ‘data, warrant, so claim’. For the yet more general schema: ‘premise; (...) if premise, then conclusion; so conclusion’, we forward a meta-level CQ-list that is arguably both complete and applicable. This list should inform ongoing theoretical efforts at generating appropriate object-level CQs for specific argument schemes. (shrink)

I criticize a case made by George Bowles for a certain theory pertaining to the evaluation of arguments on which the (degree of) attributed favourable relevance of an argument's premises to its conclusion is relevant to its evaluation, but nevertheless argue that such favourable relevance is indeed relevant to an argument's evaluation.

Popular textbook treatments of the fallacies approach to argument evaluation employ the Adversary Method identified by Janice Moulton (1983) that takes the goal of argumentation to be the defeat of other arguments and that narrows the terms of discourse in order to facilitate such defeat. My analysis of the textbooks shows that the Adversary Method operates as a Kuhnian paradigm in philosophy, and demonstrates that the popular fallacies pedagogy is authoritarian in being unresponsive to the scholarly developments in (...) informal logic and argumentation theory. A progressive evolution for the fallacies approach is offered as an authoritative alternative. (shrink)

The paper discusses intention as a rhetorical key term and argues that a consideration of rhetor’s intent should be maintained as relevant to both the production and critique of rhetorical discourse. It is argued that the fact that the critic usually has little or no access to the rhetor’s mind does not render intention an irrelevant factor. Rather than allowing methodological difficulties to constrain critical inquiry, I suggest some ways in which the critic can incorporate the rhetor’s intention in evaluating (...) argumentation. To this end, a standard of fairness is presented. (shrink)

Even though tools for identifying and analyzing arguments are now in wide use in the field of argumentation studies, so far there is a paucity of resources for evaluating real arguments, aside from using deductive logic or Bayesian rules that apply to inductive arguments. In this paper it is shown that recent developments in artificial intelligence in the area of computational systems for modeling defeasible argumentation reveal a different approach that is currently making interesting progress. It is shown how these (...) systems provide the general outlines for a system of argument evaluation that can be applied to legal arguments as well as everyday conversational arguments to assist a user to evaluate an argument. (shrink)

Building upon the role values take in Walton’s theory of practical reasoning, this paper will frame the question of how values should be evaluated into the broader question of what reasonable practical argumentation is. The thesis argued for is that if a positive evaluation of practical reasoning argumentation requires that the argument avoid a morally negative conclusion, then the role of values should be given a central, rather than supportive, position in practical argument evaluation.

Argument evaluation, the ability to separate prior belief from evaluation of the quality of an argument, is an essential element of critical thinking. The present study examined the ability of three personality traits (dogmatism, openness to experience, and open-mindedness) to predict argument evaluation quality and belief bias. One hundred and twelve undergraduate students completed the Argument Evaluation Test (Stanovich & West, 1997), measures of Dogmatism, Open-Mindedness, Openness to Experience, and a Vocabulary test. (...) Argument Evaluation Quality was negatively related to Dogmatism, and positively related to Openness to Experience and Vocabulary. Path analysis showed that, when controlling for Vocabulary, Dogmatism was the only personality variable that significantly (negatively) predicted Argument Evaluation Quality. None of the variables in our study were related to belief bias. Implications for future research and educational practice are discussed. (shrink)

An argumentative passage that might appear to be an instance of denying the antecedent will generally admit of an alternative interpretation, one on which the conditional contained by the passage is a preface to the argument rather than a premise of it. On this interpretation. which generally is a more charitable one, the conditional plays a certain dialectical role and, in some cases, a rhetorical role as welL Assuming only a very weak principle of exigetical charity, I consider what (...) it would take in a given case to justify accepting the less charitable interpretation. I then present evidence that those conditions are seldom met. Indeed, I was unable to find a single published argument that can justifiably be charged with denying the antecedent. (shrink)

Rozszerzona wersja wykładów Gilbert Ryle wygłoszonych na Trent University, Peterborough, Ontario w Kanadzie w 1984 roku.

Toulmin’s scheme for the layout of arguments (1958, The Uses of Argument, Cambridge University Press, Cambridge) represents an influential tool for the analysis of arguments. The scheme enriches the traditional premises-conclusion model of arguments by distinguishing additional elements, like warrant, backing and rebuttal. The present paper contains a formal elaboration of Toulmin’s scheme, and extends it with a treatment of the formal evaluation of Toulmin-style arguments, which Toulmin did not discuss at all. Arguments are evaluated in terms of (...) a so-called dialectical interpretation of their assumptions. In such an interpretation, an argument’s assumptions can be evaluated as defeated, e.g., when there is a defeating reason against the assumption. The present work builds on recent research on defeasible argumentation (cf. e.g. the work of Pollock, Reiter, Loui, Vreeswijk, Prakken, Hage and Dung). More specifically, the author’s work on the dialectical logic DEFLOG and the argumentation tool ARGUMED serve as starting points. (shrink)

Animals today and tomorrow -- What makes an argument? -- Should animals be used in rodeo sports? -- Should animals be kept as pets? -- Should zoos and safari parks be banned?

Many philosophers believe that our ordinary English words man and woman are “gender terms,” and gender is distinct from biological sex. That is, they believe womanhood and manhood are not defined even partly by biological sex. This sex/gender distinction is one of the most influential ideas of the twentieth century on the broader culture, both popular and academic. Less well known are the reasons to think it’s true. My interest in this paper is to show that, upon investigation, the arguments (...) for the sex/gender distinction have feet of clay. In fact, they all fail. We will survey the literature and tour arguments in favor of the sex/gender distinction, and then we’ll critically evaluate those arguments. We’ll consider the argument from resisting biological determinism, the argument from biologically intersex people and vagueness, the argument from the normativity of gender, and some arguments from thought experiments. We’ll see that these arguments are not up to the task of supporting the sex/gender distinction; they simply don’t work. So, philosophers should either develop stronger arguments for the sex/gender distinction, or cultivate a variety of feminism that’s consistent with the traditional, biologically-based definitions of woman and man. (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 critical examination of the dialectical approach, focusing on a comparison ofthe illative and the dialectical definitions of argument. I distinguish a moderate, a strong and a hyper dialectical conception of argument. I critique Goldman's argument for the moderate conception and Johnson's argument for the strong conception, and argue that the moderate conception is correct.

In this paper I will defend the controversial thesis that all argumentation in natural language can be reconstructed, for the purposes of assessment, as a deductively valid argument. Evaluation of the argumentation amounts to evaluation of the logical coherence of the premises. I will be taking the pragma-linguistic theory of Bermejo-Luque as an initial starting point.

In studying how lay people evaluate arguments, psychologists have typically focused on logical form and content. This emphasis has masked an important yet underappreciated aspect of everyday argument evaluation: social cues to argument strength. Here we focus on the ways in which observers evaluate arguments by the reaction they evoke in an audience. This type of evaluation is likely to occur either when people are not privy to the content of the arguments or when they are (...) not expert enough to appropriately evaluate it. Four experiments explore cues that participants might take into account in evaluating arguments from the reaction of the audience. They demonstrate that participants can use audience motivation, expertise, and size as clues to argument quality. By contrast we find no evidence that participants take audience diversity into account. (shrink)

The article shows how, by changing the formulations of habitual premises and critical questions for pre­sumptive argumentation schemes, one can evaluate an argument even before its type has become known. The argument from position to know is used to justify the possibility of detecting types of classical pre­sumptive schemes when we take into account the type of speech act used to implement them, and the speaker and listener’s awareness of each other’s propositional attitudes. The types of argument (...) from posi­tion to know are distinguished with respect to their epistemic and illocutionary variety. Following Austin one of these types can be considered a performative argument from position to know. The article describes the principles of its usage and outlines the evaluation procedure. (shrink)

We are pleased to publish this WSIA edition of Trudy’s Govier’s seminal volume, Problems in Argument Analysis and Evaluation. Originally published in 1987 by Foris Publications, this was a pioneering work that played a major role in establishing argumentation theory as a discipline. Today, it is as relevant to the field as when it first appeared, with discussions of questions and issues that remain central to the study of argument. It has defined the main approaches to many (...) of those issues and guided the ways in which we might respond to them. From this foundation, it sets the stage for further investigations and emerging research. This is a second edition of the book that is corrected and updated by the author, with new prefaces to each chapter. (shrink)

In this paper, we formulate a procedure for assessing reasoning as it is expressed in natural arguments. The procedure is a specification of one of the three aspects of argumentation assessment distinguished in the Comprehensive Assessment Procedure for Natural Argumentation that makes use of the argument categorisation framework of the Periodic Table of Arguments. The theoretical framework and practical application of both the CAPNA and the PTA are described, as well as the evaluation procedure that combines the two. (...) The procedure is illustrated through an evaluation of the reasoning of two example arguments from a recently published text. (shrink)

This paper explores the outlines of a framework for evaluating arguments. Among the factors to take into account are the strength of the arguers' inferences, the level of their engagement with objections raised by other interlocutors, and their effectiveness in rationally persuading their target audiences. Some connections among these can be understood only in the context of meta-argumentation and meta-rationality. The Principle of Meta-Rationality (PMR)--that reasoning rationally includes reasoning about rationality-is used to explain why it can be rational to resist (...) dialectically satisfying arguments or accept logically flawed ones. (shrink)

How does the analysis and evaluation of argumentation depend on the dialogue type in which the argumentation has been put forward? This paper focuses on argumentative bluff in eristic discussion. Argumentation cannot be presented without conveying the pretence that it is dialectically reasonable, as well as, at least to some degree, rhetorically effective. Within eristic discussion it can be profitable to engage in bluff with respect to such claims. However, it will be argued that such bluffing is dialectically inadmissible, (...) even within an eristic discussion. (shrink)

This paper presents a novel argumentation framework to support Issue-Based Information System style debates on design alternatives, by providing an automatic quantitative evaluation of the positions put forward. It also identifies several formal properties of the proposed quantitative argumentation framework and compares it with existing non-numerical abstract argumentation formalisms. Finally, the paper describes the integration of the proposed approach within the design Visual Understanding Environment software tool along with three case studies in engineering design. The case studies show the (...) potential for a competitive advantage of the proposed approach with respect to state-of-the-art engineering design methods. (shrink)

A traditional diagnosis of the error in the Cartesian skeptical arguments holds that they exploit our tendencies to take a representationalist view of perception. Thinking (perhaps not too clearly) that we perceive only our own sensory states, it seems to us that our perceptual beliefs about physical objects must be justified qua explanations of those sensory states. Such justification requires us to have reasons to reject rival explanations, such as the skeptical hypotheses, which we lack. However, those who adopt the (...) direct realist view of perception still find these arguments plausible, although, according to this diagnosis, they shouldn't. To avoid this objection, I argue that the Cartesian skeptical arguments exploit, not our representationalist tendencies, but our habits for evaluating causal explanatory justifications. (shrink)

Developing critical thinking ability is one of the main goals of medical education, in part because it enhances clinical reasoning, a vital competence in clinical practice. However, there is limited evidence suggesting ways to effectively teach critical thinking in the classroom. Here, we describe the use of a drama-based critical thinking classroom scenario. The study used a mixed-methods approach with both quantitative and qualitative analysis of questionnaire responses. Ninety-one medical students in Colombia were asked to identify and evaluate arguments regarding (...) a dilemma between ethics, social responsibility and scientific work presented in the play Should’ve by the Nobel laureate Roald Hoffmann. Chi square analyses of responses to closed-ended questions showed that the drama-based classroom scenario provided learners with opportunities to make decisions, and to identify and evaluate arguments from the play. Qualitative analysis of responses to open-ended questions confirmed these findings and illustrated the processes underlying the decisions. Students were able to evaluate arguments in an impartial way. Our findings support the use of drama-based scenarios in the classroom as an approach to fostering medical students’ critical thinking. This approach could contribute to a classroom pedagogy in which all students have an active role in responding to controversial questions, evaluating arguments and critically responding. This would support the development of critical thinking and promote deeper understanding of the dilemmas involved in scientific work. (shrink)

The centrality of argumentation in the judicial process is an age-old acquisition of research on legal discourse. Notwithstanding the deep insights provided by legal theoretical and philosophical works, only recently has judicial argumentation been tackled in its linguistic dimension. This paper aims to contribute to the development of linguistic studies of judicial argumentation, by shedding light on evaluation as a prominent aspect in the construction of the judge’s argumentative position. Evaluation as a deep structure of judicial argumentation is (...) studied from a discursive point of view entailing the analysis of a sample of authentic judicial language. Evaluative lexis is investigated within a single genre of judicial discourse, i.e. judgments, instantiated by a corpus of US Supreme Court judgments. Findings show that judges use diversified strategies to take stance as they organise their argumentative discourse: from easily recognisable verbal and adjectival tools to more finely-grained discourse elements such as the encapsulating pattern ‘this/these/that/those + labelling noun’. (shrink)

The relevance of context has been acknowledged also recently as a fundamental element for the correct evaluation of argumentative moves within institutional fields of interaction. Indeed, not considering the larger culture-specific and social features of the context within which the interactions take place poses problems of interpretation of the data and comparability of results. Starting from these considerations, the paper aims at discussing a model for the description of the social context of interaction that may allow for a better (...) interpretation and evaluation of argumentative moves within medical consultations. The efficacy of the model is shown by applying it to the description and analysis of examples of real-life consultations recorded in the Italian region of Lombardy. In the first section, the model for the description of the social context of interaction is presented and discussed. In the second section, examples of argumentative passages from a selection of consultations are presented and commented on by relying on the model. Some concluding remarks and further developments of the research are proposed in the final section Keywords: communication context, argumentation in context, situated discourse, medical consultation. (shrink)