In his influential work on critical argumentation, Douglas Walton explains how to judge whether an argumentum ad verecundiam is fallacious or legitimate. He provides six critical questions and a number of ancillary sub-questions to guide the identification of reasonable appeals to authority. While it is common for informal logicians to acknowledge the role of bias in sampling procedures and hypothesis confirmation , there is a conspicuous lack of discourse on the effect of identity prejudice on judgments of authority, even though (...) this is a well-documented factor in attributing credibility, expertise, trustworthiness, and professional competence to oppressed groups. This could result in faulty judgments of ad verecundiam fallacy. Focusing on gender bias, I review recent works in feminist epistemology—particularly those of Miranda Fricker and Helen Longino —to develop three gender-based critical questions to supplement Walton’s original list of six. This addition will help us to identify erroneous dismissals of appeals to authority based on epistemic injustice and epistemic irresponsibility on the part of the speaker or knowledge community. This project promotes the overlapping aims of feminist epistemology and informal logic. (shrink)

Trust is a natural mechanism by which an autonomous party, an agent, can deal with the inherent uncertainty regarding the behaviours of other parties and the uncertainty in the information it shares with those parties. Trust is thus crucial in any decentralised system. This paper builds on recent efforts to use argumentation to reason about trust. Specifically, a set of schemes is provided, and abstract patterns of reasoning that apply in multiple situations geared towards trust. Schemes are described in which (...) one agent, A, can establish arguments for trusting another agent, B, directly, as well as schemes that A can use to construct arguments for trusting C, where C is trusted by B. For both sets of schemes, a set of critical questions is offered that identify the situations in which these schemes can fail. (shrink)

The public must make assessments of a range of health-related issues. However, these assessments require scientific know-ledge which is often lacking or ineffectively utilized by the public. Lay people must use whatever cognitive resources are at their disposal to come to judgement on these issues. It will be contended that a group of arguments—so-called informal fallacies—are a valuable cognitive resource in this regard. These arguments serve as cognitive heuristics which facilitate reasoning when knowledge is limited or beyond the grasp of (...) reasoners. The results of an investigation into the use of these arguments by the public are reported. (shrink)

. While courts depend on expert opinions in reaching sound judgments, the role of the expert witness in legal proceedings is associated with a litany of problems. Perhaps most prevalent is the question of under what circumstances should testimony be admitted as expert opinion. We review the changing policies adopted by American courts in an attempt to ensure the reliability and usefulness of the scientific and technical information admitted as evidence. We argue that these admissibility criteria are best seen in (...) a dialectical context as a set of critical questions of the kind commonly used in models of argumentation. (shrink)

This paper takes an argumentation approach to find the place of trust in a method for evaluating arguments from expert opinion. The method uses the argumentation scheme for argument from expert opinion along with its matching set of critical questions. It shows how to use this scheme in three formal computational argumentation models that provide tools to analyse and evaluate instances of argument from expert opinion. The paper uses several examples to illustrate the use of these tools. A conclusion of (...) the paper is that from an argumentation point of view, it is better to critically question arguments from expert opinion than to accept or reject them based solely on trust. (shrink)

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 notions of types of dialogue and dialectical relevance are central themes in Walton’s work and the grounds for a dialectical approach to many fallacies. After outlining the dialogue models constituting the background of Walton’s account, this article presents the concepts of dialectical relevance and dialogue shifts in their application to biased argumentation, fallacious moves, and illicit argumentative strategies. Showing the different dialectical proposals Walton advanced in several studies on argumentation as a development of a dialogical system, it has proved (...) possible to highlight the fundamental aspects of his theory in a comprehensive model of communication and interaction. (shrink)

Richard Whately’s views of arguments involving authority are very different in his Elements of Rhetoric and his Elements of Logic. This essay begins by documenting these differences and wondering why they are. It then proceeds to take a broader and more historical view of Whately’s discussions of authority and finds him occupying an important developmental ground between his predecessor Locke and contemporary views of the argument from authority. In fact, some of the things we now think are important in a (...) good argument from authority are anticipated by Whately. (shrink)

In this article, I further analyze the notion of the effectiveness of argumentative strategies, introduced in Jovičić, 2001. The most relevant achievements of the theories of reasonable discussion and the theories of persuasion are called to mind with the aim of explaining the mechanism of the argumentative effectiveness. As a result, a procedure for evaluating the effectiveness of argumentative strategies is suggested.

False dilemma is a specific form of reasoning : despite the fact that it is based on a deductively valid argument form, it is rightly depicted as fallacy. A systematic exposition of false dilemma is missing in theoretical approaches to fallacies. This article formulates six criteria for a well-grounded exposition of a fallacy, suggesting also a systematic exposition of false dilemma. These criteria can be used to both explain, and categorise, the various false dilemma fallacies. The article introduces distinction between (...) four types of false dilemma : False quandary, Defeasible sound quandary, False obstruction and Defeasible sound obstruction. The types of criticism appropriate for each variant of false dilemma are suggested. Being able to discover false dilemma in situations when it is important to make good and free choices is a significant dimension of critical thinking. It may liberate us from accepting the consequences that necessarily follow from prearranged alternatives, when these are not the only alternatives possible. It may also liberate us from refraining from actions on the basis of obstructive disjunctive statements. In that respect, the faculty of critical thinking directed at uncovering reasoning based on false dilemma may also initiate the discovery of new alternatives, or discover the ways of unifying seemingly opposing alternatives. Thus, a well-developed ability to understand the tricky argumentative moves of false dilemma may be a good step towards initiating some features of creative thinking. (shrink)

Recent sociological/philosophical treatments of expertise, best represented by the work of Steve Fuller, attempt to (1) reduce displays of expertise to sophistic exercises of discretionary power, and (2) refute the claim that because laypeople are epistemically inferior to experts, it is rational to defer to an expert's opinion rather than making up one's own mind. But upon inspection, Fuller fails to provide reasonable grounds for liberating laypeople from the tyranny of cognitive authoritarianism. Rather, he presents a patronizing description of the (...) expert‐lay relation, one that actually makes the public seem more ignorant than is warranted. (shrink)

Work in Argumentation Studies (AS) and Studies in Expertise and Experience (SEE) has been proceeding on converging trajectories, moving from resistance to expert authority to a cautious acceptance of its legitimacy. The two projects are therefore also converging on the need to account for how, in the course of complex and confused civic deliberations, nonexpert citizens can figure out which statements from purported experts deserve their trust. Both projects recognize that nonexperts cannot assess expertise directly; instead, the nonexpert must judge (...) whether to trust the expert. But how is this social judgment accomplished? A normative pragmatic approach from AS can complement and extend the work from SEE on this question, showing that the expert’s putting forward of his view and “bonding” it with his reputation for expertise works to force or “blackmail” his audience of citizens into heeding what he says. Appeals to authority thus produce the visibility and accountability we want for expert views in civic deliberations. (shrink)

Different approaches to expertise and argumentation are discussed. After introducing the problem of expertise and its present day significance in a historical context, various connections with the study of arguments are highlighted. The need for and potential of argumentation analysis to contribute to existing research in social epistemology, science studies, and cognitive science, is discussed, touching on the problems of reasoning and argumentation, embodiment, tacit knowledge, expert context versus public context, expert disagreement, persuasion versus justification, and argument analysis as meta-expertise. (...) As the arguments used by experts constitute a boundary object, we presume that a dialogue format is suitable to address central problems of the special issue “Rethinking Arguments from Experts”. (shrink)

I discuss under what conditions the objection that an expert’s argument is biased by her self-interest can be a meaningful and sound argumentative move. I suggest replacing the idea of bias qua self-interest by that of a conflict of interests, exploit the distinction between an expert context and a public context, and hold that the objection can be meaningful. Yet, the evaluation is overall negative, because the motivational role of self-interest for human behavior remains unclear. Moreover, if recent social-psychological results (...) from the “heuristics and biases” program are accepted, it is plausible to assume that humans also satisfice (rather than optimize/maximize) when identifying and then acting in their self-interest. My thesis is: insofar as the objection is sound with a particular audience, it is not needed; and insofar as the objection is needed, it is unsound. (shrink)

In this paper, I argue that ad hominem arguments are not always fallacious. More explicitly, in certain cases of practical reasoning, the circumstances of a person are relevant to whether or not the conclusion should be accepted. This occurs, I suggest, when a person gives advice to others or prescribes certain courses of action but fails to follow her own advice or act in accordance with her own prescriptions. This is not an instance of a fallacious tu quoque provided that (...) such circumstantial ad hominem arguments are construed as rebuttals to appeals (administrative) authority (of expertise), or so I argue. (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)

In this paper, I try to develop an informal model for the analysis and evaluation of argumentative strategies based on active authorities. The explanations necessary to understand the idea of the model and what is modelled are given through the development of the paper. I first give an example of argumentative activities. After that, the main assumption of the model is given. In the third part, the relevant aspects of the argumentative activity are analysed, while the principles of the evaluation (...) are explained in the fourth part. The informal model is presented in the fifth part. In the final remarks, the suggestions for further work are given, as well as a comparison with some related recent works in argumentation theory. (shrink)

Dreyfus's model of expert skill acquisition is philosophically important because it shifts the focus on expertise away from its social and technical externalization in STS, and its relegation to the historical and psychological context of discovery in the classical philosophy of science, to universal structures of embodied cognition and affect. In doing so he explains why experts are not best described as ideologues and why their authority is not exclusively based on social networking. Moreover, by phenomenologically analyzing expertise from a (...) first person perspective, he reveals the limitations of, and sometimes superficial treatment that comes from, investigating expertise from a third person perspective. Thus, he shows that expertise is a prime example of a subject that is essential to science but can only be fully elaborated with the aid of phenomenological tools. However, both Dreyfus's descriptive model and his normative claims are flawed due to the lack of hermeneutical sensitivity. He assumes an expert's knowledge has crystallized out of contextual sensitivity plus experience, and that an expert has shed, during the training process, whatever prejudices, ideologies, hidden agendas, or other forms of cultural embeddedness, that person might have begun with. One would never imagine, from Dreyfus's account, that society could possibly be endangered by experts, only how society's expectations and actions could endanger experts. The stories of actual controversies not only shows things do not work the way Dreyfus claims, but also that it would be less salutary if they did. Such stories amount to counterexamples to Dreyfus's normative claims, and point to serious shortcomings in his arguments. (shrink)

The aim of the paper is to present a typology of argument schemes. In first place, we found it helpful to define what an argument scheme is. Since many argument schemes found in contemporary theories stem from the ancient tradition, we took in consideration classical and medieval dialectical studies and their relation with argumentation theory. This overview on the main works on topics and schemes provides a summary of the main principles of classification. In the second section, Walton’s theory is (...) briefly explained to introduce the schemes classification and its different levels. At least, the final part shows the main application of the schemes in computing and AI. -/- . (shrink)

This paper studies the modelling of legal reasoning about evidence within general theories of defeasible reasoning and argumentation. In particular, Wigmore's method for charting evidence and its use by modern legal evidence scholars is studied in order to give a formal underpinning in terms of logics for defeasible argumentation. Two notions turn out to be crucial, viz. argumentation schemes and empirical generalisations.

The Holy Scriptures can be considered a specific kind of normative texts, whose use to assess practical moral cases requires interpretation. In the field of ethics, this interpretative problem results in the necessity of bridging the gap between the normative source – moral precepts – and the specific cases. In the history of the Church, this problem was the core of the so-called casuistry, namely the decision-making practice consisting in applying the Commandments and other principles of the Holy Scriptures to (...) specific cases or moral problems. By taking into account the sin of lying, this paper argues that casuistic texts reveal an extremely sophisticated interpretative method, grounded on “pragmatic” contextual and communicative considerations and argumentative structures that resemble the ones used in legal interpretation. These works show how the underspecified biblical text expressing an abstract norm was enriched pragmatically by completing it and modulating its meaning so that it could be used to draw a conclusion in a specific context on a specific case. The mutual interdependence between biblical interpretation, pragmatics, and argumentation sheds light on a much broader phenomenon, namely the pragmatic nature of argumentation. (shrink)

Everyday life reasoning and argumentation is defeasible and uncertain. I present a probability logic framework to rationally reconstruct everyday life reasoning and argumentation. Coherence in the sense of de Finetti is used as the basic rationality norm. I discuss two basic classes of approaches to construct measures of argument strength. The first class imposes a probabilistic relation between the premises and the conclusion. The second class imposes a deductive relation. I argue for the second class, as the first class is (...) problematic if the arguments involve conditionals. I present a measure of argument strength that allows for dealing explicitly with uncertain conditionals in the premise set. (shrink)

Ethotic arguments, such as arguments from expert opinion and ad hominem arguments, play an important role in communication practice. In this paper, we argue that there is another type of reasoning from ethos, in which people argue about actions in the world. These subspecies of ethotic arguments are very common in public debates: societies are involved in heated disputes about what should be done with monuments of historical figures such as Stalin or Colston: Should we demolish the building they funded? (...) Should we revere their statues? Should the street named after them be renamed?; and the general public vividly argue about what should be done with the legacy of producers, directors and actors in debates of the #MeToo movement: Should their new movies be distributed? Should their scenes be deleted from motion pictures? Should their stars from the Hollywood Walk of Fame be removed? Many arguments in these debates boil down to the character of the public figures: He was a slave trader!—But he is a part of our history; He harassed a young girl!—But he is an important actor. The reasoning step here is legitimised by the association between a person and an extra-linguistic object: the association between a historical figure and their statue or between an actor and their movie. The nature of this association is explained in the paper using Peirce’s theory of signs. We propose to extend an existing approach to patterns of reasoning from ethos that will help us to shed new light on ethotic argumentation and open an avenue for a systematic account of these unexplored argument forms. (shrink)

Douglas Walton’s multitudinous contributions to the study of argumentation seldom, if ever, directly engage with argumentation in mathematics. Nonetheless, several of the innovations with which he is most closely associated lend themselves to improving our understanding of mathematical arguments. I concentrate on two such innovations: dialogue types (§1) and argumentation schemes (§2). I argue that both devices are much more applicable to mathematical reasoning than may be commonly supposed.

Recent disputes :57–79, 2013; Mizrahi in Inform Logic 36:238–252, 2016; Mizrahi in Argumentation 32:175–195, 2018; Seidel in Inform Logic 34:192–218, 2014; Seidel in Inform Logic 36:253–264, 2016; Hinton in Inform Logic 35:539–554, 2015) on the strength of arguments from expert opinion give rise to a potential legitimacy crisis of it. Mizrahi :57–79, 2013; Inform Logic 36:238–252; Argumentation 32:175–195, 2018) claims that AEO are weak arguments by presenting two independent arguments. The first argument is that AEO are weak arguments because empirical (...) studies show that expert opinions p do not make p significantly more likely to be true. The second argument is that AEO are weak arguments because empirical studies show that expert opinions are susceptible to the kinds of cognitive biases that novice opinions are susceptible to. In this paper, I intend to argue that Mizrahi’s two arguments both fail because of inconsistency, irrelevance, and insufficiency. Nevertheless, Mizrahi’s arguments help to evaluate AEO better by expanding the relevant critical questions. (shrink)

The analysis of multimodal argumentation in advertising is a crucial and problematic area of research. While its importance is growing in a time characterized by images and pictorial messages, the methods used for interpreting and reconstructing the structure of arguments expressed through verbal and visual means capture only isolated dimensions of this complex phenomenon. This paper intends to propose and illustrate a methodology for the reconstruction and analysis of “double-mode” arguments in advertisements, combining the instruments developed in social semiotics, pragmatics, (...) and argumentation theory. An advertisement is processed through a five-step path. The analysis of its context, text genre, and images leads to a first representation of the messages that it encodes both pictorially and verbally (step 1). These first semantic representations are further enriched by including their polyphonic articulations and presuppositions (step 2), their explicatures (step 3), and their dialogical functions and illocutionary forces (step 4). These pragmatic steps retrieve the commitment structure of the ad, which allows a further argument analysis conducted through argumentation schemes (step 5). (shrink)

This work pretends to unveil the relationship between the psychosocial features grouped under the argument frame concept and the degree of discursive density that is reached by a sample of 243 older adults in the production of argumentative discourses. In order to specify the main psychosocial features of the sample’s subjects, the Hample test was employed. In order to evaluate argumentative density, all of the participants were asked for an essay about a controversial situation derived from the Dilemma of the (...) D.I.T. Questionnaire. The information crossover between both instruments allowed the establishment of a significant relationship between the way in which the older adults frame reality and the discursive products through which it is communicated. (shrink)

Epistemic democrats are rightly concerned with the quality of outcomes and judge democratic procedures in terms of their ability to ‘track the truth’. However, their impetus to assess ‘rule by experts’ and ‘rule by the people’ as mutually exclusive has led to a meagre treatment of the role of expert knowledge in democracy. Expertise is often presented as a threat to democracy but is also crucial for enlightened political processes. Contemporary political philosophy has so far paid little attention to our (...) reliance on experts and has not sufficiently addressed the question of how expertise can be used to improve the epistemic quality of democratic decision making. We believe this lack of interest is spurred by a too hasty acceptance of arguments dismissive of the political role of experts. The article examines a series of often-cited epistemic objections and concludes that several of them are overstated or misconceived, yet they all reflect real difficulties that need to be addressed. On this background, we tentatively outline a set of mechanisms that can contribute to alleviating the irreducible problem of epistemic asymmetries and ensuring that experts really are experts and use their expertise in the right way. (shrink)

In this paper, I contend that evidence-focused strategies of science communication may be complemented by possibly more effective rhetorical arguments in current public debates on vaccines. I analyse the case of direct science communication - that is, communication of evidence - and show that it is difficult to effectively communicate evidential standards of science in the presence of well-equipped anti-science movements. Instead, I argue that effective rhetorical tools involve ad hominem strategies, that is, arguments involving claims of expertise. I provide (...) a rationale, and sketch a methodology, for using ad hominem arguments in science communication. (shrink)

Despite being a new term, ‘fake news’ has evolved rapidly. This paper argues that it should be reserved for cases of deliberate presentation of false or misleading claims as news, where these are misleading by design. The phrase ‘by design’ here refers to systemic features of the design of the sources and channels by which fake news propagates and, thereby, manipulates the audience’s cognitive processes. This prospective definition is then tested: first, by contrasting fake news with other forms of public (...) disinformation; second, by considering whether it helps pinpoint conditions for the proliferation of fake news. (shrink)

In this paper we show that an essential aspect of solving the problem of uncritical acceptance of expert opinions that is at the root of the ad verecundiam fallacy is the need to disentangle argument from expert opinion from another kind of appeal to authority. Formal and computational argumentation systems enable us to analyze the fault in which an error has occurred by virtue of a failure to meet one or more of the requirements of the argumentation scheme from argument (...) from expert opinion. We present a method for enhancing this capability by showing how arguments from expert opinion are related to, but different from, arguments from deontic authority. (shrink)

In this article author traces relation between argumentation and cultural practice. The first part focuses on definition of argumentation in informal logic tradition. In particular, it discusses argument in terms of verbal and social activity involving the use of everyday language. Author claims that there is no argumentation beyond language. The second part explains persuasive argumentation as a form of cultural practice. The persuasive arguments found in “social practice” can be understood as a social activity, analysable within the context of (...) a given cultural system. Author refers to an approach taking the argumentative expression as a certain type of communicative practice, directed towards respecting, recognising or accepting specific actions. The inclusion of persuasive argumentation in the “circuit of cultural activities” to be studied makes it possible to compare this type of argumentation with other social practices, and to posit a clear historical dimension in the study of argumentation. It also makes it possible to view persuasive argumentation as one of many cultural activities aimed at changing or perpetuating behaviours, attitudes, thinking, etc. The third part of the paper concerns the problem of humanistic interpretation of persuasive argumentation. Author attempts to develop this intuition, at the same time demonstrating the problems that arise from this approach. In conclusion, author tries to analyze argumentation in terms of culture theory and humanistic interpretation. (shrink)

The history of fallacy theory is long, distinguished and, admittedly, checkered. I offer a bird eye view on it, with the aim of contrasting the standard conception of fallacies as attractive and universal errors that are hard to eradicate with the contemporary preoccupation with “non-fallacious fallacies”, that is, arguments that fit the bill of one of the traditional fallacies but are actually respectable enough to be used in appropriate contexts. Godden and Zenker have recently argued that reinterpreting alleged fallacies as (...) non-fallacious arguments requires supplementing the textual material with something else, e.g. probability distributions, pragmatic considerations, dialogical context. Thus fallacies remain gappy on all accounts, and this is the hallmark of their failure. However, I argue that such gappiness is typically unproblematic, and thus no more flawed than enthymematic argumentation in general. This, in turn, calls into question the usefulness of the very notion of fallacy. (shrink)

The contribution critically discusses Walton's argumentation scheme approach. On the one hand, its enormous richness and closeness to the empirical argumentation material is appreciated, but, on the other, fundamental conceptual weaknesses are revealed. Although the approach more recently has been declared to strive for “true beliefs and correct choices” it has not systematically developed the proposed schemes in a way that these goals are reached. Accordingly, many proposed schemes are fallacious from an epistemological standpoint.

The appeal to expert opinion is an argument form that uses the verdict of an expert to support a position or hypothesis. A previous scheme-based treatment of the argument form is formalized within a Bayesian network that is able to capture the critical aspects of the argument form, including the central considerations of the expert's expertise and trustworthiness. We propose this as an appropriate normative framework for the argument form, enabling the development and testing of quantitative predictions as to how (...) people evaluate this argument, suggesting that such an approach might be beneficial to argumentation research generally. We subsequently present two experiments as an example of the potential for future research in this vein, demonstrating that participants' quantitative ratings of the convincingness of a proposition that has been supported with an appeal to expert opinion were broadly consistent with the predictions of the Bayesian model. (shrink)

In spite of significant research efforts, argument technologies do not seem poised to scale up as much as most commentators would hope or even predict. In this paper, I discuss what obstacles bar the way to more widespread success of argument technologies and venture some suggestions on how to circumvent such difficulties: doing so will require a significant shift in how this research area is typically understood and practiced. I begin by exploring a much broader yet closely related question: To (...) what extent are people natively good at arguing? This issue has always been central to philosophical reflection and it has become even more urgent nowadays, with the explosion of persuasive technologies and unprecedented opportunities for large-scale social influence. The answer hinges on what aspect of argumentation is taken under consideration: evidence suggests that people are relatively bad at analyzing the structure of arguments, especially when these are presented out of context and in abstract terms; in contrast, data show that even laymen tend to excel in the interactive practice of argumentation, in particular when motivation is high and something significant is at stake. Unfortunately, current argument technologies are more closely tailored to the former type of activity than to the latter, which is the main reason behind their relative lack of success with the general public. Changing this state of affair will require a commitment to ecological argument technologies: that is, technologies designed to support real-time, engaging and meaningful argumentative interactions performed by laypeople in their ordinary life, instead of catering to the highly specific needs of a minority of niche users. (shrink)

In this paper, I will try to answer the question: How are we supposed to assess the expert’s opinion in an argument from the position of an outsider to the specialized field? by placing it in the larger context of the political status of epistemic authority. In order to do this I will first sketch the actual debate around the problem of expertise in a democracy and relate this to the issue of the status of science in society. Secondly, I (...) will review how Douglas Walton’s pragma-dialectical approach offers a practical procedure to assess the expert bias from a nonprofessional’s perspective. Thirdly, I will introduce the problem of group bias using insights from Bohman and Fischer and show how Walton’s solution does not address this specific type of bias. Lastly, I will try proposing a revision of Walton’s solution in order to address this problem. In order to make the explanation more easy to follow I will use a case study concerning the medical expertise in the public debate on second-hand smoke. (shrink)

The aim of this investigation is to explore the role of argumentation schemes in enthymeme reconstruction. This aim is pursued by studying selected cases of incomplete arguments in natural language discourse to see what the requirements are for filling in the unstated premises and conclusions in some systematic and useful way. Some of these cases are best handled using deductive tools, while others respond best to an analysis based on defeasible argumentations schemes. The approach is also shown to work reasonably (...) well for weak arguments, a class of arguments that has always been difficult to analyze without the principle of charity producing a straw man. (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)

When the likelihood ratio approach is employed for evidential reasoning in law, it is often necessary to employ subjective probabilities, which are probabilities derived from the opinions and judgement of a human. At least three concerns arise from the use of subjective probabilities in legal applications. Firstly, human beliefs concerning probabilities can be vague, ambiguous and inaccurate. Secondly, the impact of this vagueness, ambiguity and inaccuracy on the outcome of a probabilistic analysis is not necessarily fully understood. Thirdly, the provenance (...) of subjective probabilities and the associated potential sources of vagueness, ambiguity and inaccuracy tend to be poorly understood, making it difficult for the outcome of probabilistic reasoning to be explained and validated, which is crucial in legal applications. The former two concerns have been addressed by a wide body of research in AI. The latter, however, has received little attention. This paper presents a novel approach to employ argumentation to reason about probability distributions in probabilistic models. It introduces a range of argumentation schemes and corresponding sets of critical questions for the construction and validation of argument models that define sets of probability distributions. By means of an extended example, the paper demonstrates how the approach, argumentation schemes and critical questions can be employed for the development of models and their validation in legal applications of the likelihood ratio approach to evidential reasoning. (shrink)

The present essay discusses a notorious rhetoric means familiar to all scholars in the social sciences and humanities including philosophy: name-dropping. Defined as the excessive over-use of authoritative names, I argue that it is a pernicious practice leading to collective disorientation in spoken discourse. First, I discuss name-dropping in terms of informal logic as an ad verecundiam-type fallacy. Insofar this perspective proves to lack contextual sensitivity, name-dropping is portrayed in Goffman’s terms as a more general social practice. By narrowing down (...) the focus to social science and the humanities, the essay emphasizes its function of discursive legitimation. This view, I argue, is incomplete because it overlooks the basic mechanism beneath. Names not only provide legitimation of but also orientation in discourse. Consequently, two tipping points—detour and disorientation—are proposed as benchmarks for it to become problematic. The conclusion re-widens the argument’s scope by suggesting questions for future inquiries. (shrink)

In academic contexts the appeal to authority is a quite common but seldom tested argument, either because we accept the authority without questioning it, or because we look for alternative experts or reasons to support a different point of view. But, by putting ourselves side by side an already accepted authority, we often rhetorically manoeuvre to displace the burden of the proof to avoid the fear to present our opinions and to allow face saving.

As appeals to expert authority shift from “fallacies” to “argument schemes,” argumentation theorists are called on to provide critical questions for assessing them. I argue that current treatments focus too heavily on assessing expertise, and not enough on judging trustworthiness. I propose instead a norma-tive pragmatic account of the rational force of the appeal to expert authority, one that emphasizes the ex-pert's actions in constructing his/her own legitimate trustworthiness.

The paper emphasizes significant resemblances between the Informal Logic Initiative and the Lvov-Warsaw School – the Polish philosophical movement, the rise of which is associated with “the Golden Age of Science and Letters”. The correspondence between informal logic and the logical studies of the LWS will be explored by discussing their subject-matter, goals, and methods. The project focused on applying logical studies of the LWS in analyzing and assessing arguments will be proposed.

Arguments which in their premises or warrants touch basic norms and values of a cultural community can be defined as culture sensitive. The paper will demonstrate how insensitivity to the cultural backgrounds of audiences may spoil an argument, and identify which kinds of arguments prove particularly open to cultural sensitivity. It will define the areas on which cultural communities may differ and determine how this bears on problems of globalization and political correctness.