Teaching Argumentation Analysis and Critical Thinking in the Netherlands.

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)

Interaction mining is about discovering and extracting insightful information from digital conversations, namely those human?human information exchanges mediated by digital network technology. We present in this article a computational model of natural arguments and its implementation for the automatic argumentative analysis of digital conversations, which allows us to produce relevant information to build interaction business analytics applications overcoming the limitations of standard text mining and information retrieval technology. Applications include advanced visualisations and abstractive summaries.

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)

The paper critically discusses an empirical study by Mizrahi & Dickinson 2020, which analyzes in a huge data base (JSTORE) the incidence of three types of philosophical arguments. Their results are: 1. Deductive arguments were the most commeon type of argument in philosophy until the end of the 20th century. 2. Around 2008 a shift in methodology occurred, such that the indcutive arguments outweigh other types of argument. The paper, first, criticizes the empirical study as grossly false and considers the (...) - very limited - possibilities of recognition of argument types by present computer programs. (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)

It has been argued that livestock farming is necessary to feed a growing population, that it enables efficient use of land and biomass that would otherwise be lost from the food system, that it produces manure that is necessary for crop cultivation, and helps improve the sustainability of cropping systems by inclusion of perennial forage crops in otherwise low-diversity crop rotations. In this paper, we analyze these arguments in favor of livestock farming. Through argumentation analysis based on scientific data, (...) we show that the arguments are either invalid or that their validity is limited to certain circumstances. Without taking into consideration any other potential arguments for livestock farming, or arguments against it, we conclude that the arguments analyzed here cannot in isolation provide justification for more than a small proportion of today’s livestock farming. (shrink)

Dialectical Situations and Argument Analysis.

In The Uses of Argument, Stephen Toulmin proposed a model for the layout of arguments: claim, data, warrant, qualifier, rebuttal, backing. Since then, Toulmin’s model has been appropriated, adapted and extended by researchers in speech communications, philosophy and artificial intelligence. This book assembles the best contemporary reflection in these fields, extending or challenging Toulmin’s ideas in ways that make fresh contributions to the theory of analysing and evaluating arguments.

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.

W Deklaracji o przerywaniu ciąży z 1974, Kościół Katolicki argumentuje, że zygota jest człowiekiem ponieważ posiada ludzki genotyp. Artykuł przedstawia logiczną analizę tej argumentacji. Pokazuje, że argumentacja ta jest w dużym stopniu wadliwa. Tomizm pełni tu funkcję uprawo-mocnienia. Entymematyczne założenia tomistyczne są niezbędne, by w ogóle możliwe było przejście od przesłanek do wniosku. Okazuje się ponadto, że argumentacja ta zakłada tomistyczną interpretację pojęć biologicznych, która jest niezgodna ze współczesną wiedzą biologiczną. Twierdzenie zawarte w Deklaracji nie zostało więc skutecznie uargumentowane na (...) gruncie biologii, a wręcz wydaje się, że biologia je wyklucza. Jest ono możliwe jedynie jako twierdzenie metafizyczne i wyłącznie na gruncie pewnych metafizyk. (shrink)

Hans-Hermann Hoppe contends that the fact that a person has the capacity to argue entails that she has the moral right of exclusive control over her own body. Critics of Hoppe’s argument do not appear to have pinpointed its flaws. I expose the logical structure of Hoppe’s argument, distinguishing its pragmatic-contradiction and its mutual-recognition components. I provide three counterexamples to show that Hoppe’s mutual-recognition argument is invalid and I argue that the truth that appears to motivate the argument is simply (...) a banality. I show that Hoppe’s pragmatic-contradiction argument is invalid, has a false premise and fails to link up with his mutual-recognition argument in the way that he requires to reach his conclusion. I conclude by outlining three perils of pragmatic-contradiction arguments, the weakness of mutual-recognition arguments, and the implausibility of attempts to derive a universal moral status from a specialised activity such as argumentation. (shrink)

In this article I scrutinise a crucial tension in understanding the debate over shale gas production in Europe. On the one hand, analyses predominantly grasp the debate in terms of pro-and-con dialectics, as if the pro-shale gas camp faced the anti-shale gas camp in a dyadic clash of opposing voices. On the other hand, it is commonly recognised that this debate is driven by multi-party and multi-position argumentative dynamics. In this broader context, I focus on one pivotal contribution to (...) the debate – Gazprom’s press release from October 2013 outlining Russia’s energy giant’s strategy of dealing with unconventional gas production. I employ concepts and methods of argumentative discourse analysis to contend that an arguer to a multi-party debate – argumentative polylogue – faces a number of constraints and opportunities that cannot be adequately grasped in terms of dyadic pro-and-con dialectics. The analysis reveals how Gazprom needs to simultaneously design its discourse to address a number of other parties who might also disagree among themselves: from Greenpeace to European Union governments to shale gas companies. I show why and how a stakeholder analysis used in organisational communication might lead to a better understanding of this form of multi-party public argumentation. (shrink)

In Swiss semi-direct democracy, citizens are often summoned to the polls. To vote reasonably, they need to be properly informed. The media therefore have the responsibility to provide them with arguments for and against each issue of voting. Here, we focus on argumentation in a television ‘civic debate’ about abolishing compulsory military service. To provide a unified and integrated overview of the debate dynamics, we combine the Dialogical Model of Argumentation and the Argumentum Model of Topics, which share a similar (...) emphasis on the discursive dimension of argumentation. This analysis underlines the importance of linguistic and communicative resources and procedures, without neglecting the macro socio-political environment of the debate. (shrink)

This paper makes use of the concepts and theoretical framework developed within the field of Argumentation Theory to account for the structure and characteristics of abduction and of the comparative processes of weighing explanatory hypothesis. It elaborates an analysis of abduction based on its consideration as a meta-explanatory argumentation scheme while elucidating its relations with abductive reasoning and inference. The conceptualization of comparative processes of weighing explanatory hypothesis as complex and varied argumentative structures is presented as an alternative (...) to the idea of providing a formally rigid and supposedly universal account of ‘inference to the best explanation’. (shrink)

In naturally occuring argumentation, words which play a crucial role in the argument often acquire different meanings on subsequent occasions of use. Traditionally, such semantic shifts have been dealt with by the ‘fallacy of equivocation’. In my paper, I would like to show that there is considerably more to semantic shifts during arguments than their potentially being fallacious. Based on an analysis of a debate on environmental policy, I will argue that shifts in meaning are produced by a principle (...) I call ‘local semantic elaboration’. I will go on to show that semantic shifts in the meaning of a word, the position advocated by a party, and the questions that the parties raise during an argumentative process are neatly tailored to one another, but can be incommensurable to the opponent's views. Semantic shifts thus may have a dissociative impact on a critical discussion. By linking the structure of argumentation to its pragmatics, however, it may be revealed that there are two practices that account for a higher order of coherence of the debate. The first practice is a general preference for disagreeing with the opponent, the second practice is the interpretation of local speech acts in terms of an overall ideological stance that is attributed to the speaker. Because of these practices, parties do not criticize divergent semantic conceptions as disruptive, but they treat them as characteristic and sometimes even metonymic reflections of the parties' positions. (shrink)

Presupposition has been described in the literature as closely related to the listener’s knowledge and the speaker’s beliefs regarding the other’s mind. However, how is it possible to know or believe our interlocutor’s knowledge? The purpose of this paper is to find an answer to this question by showing the relationship between reasoning, presumption and language. Presupposition is analyzed as twofold reasoning process: on the one hand, the speaker by presupposing a proposition presumes that his interlocutor knows it; on the (...) other hand, the listener reconstructs the propositions taken for granted and assesses them against the shared presumptions. The possibility of reconstructing a presupposition is distinguished from its assessment, where the consistency of the presupposition with the shared or common ground is evaluated, and its reasonableness established. The analysis of presuppositions from an argumentative perspective provides an instrument for evaluating the reasonableness of a presupposition and understanding its dialogical effect. On this view, the dialogical force of a presupposition lies in its presumptive nature, which sets and shifts the burden of proving its unacceptability or unreasonableness. (shrink)

This paper studies emotional inferencing triggered by emotion terms using Pragma-Dialectics and the Argumentum Model of Topics. The corpus, in French, is an excerpt of a video-recorded testimony in which a middle school teacher evokes her experience of being in class the day after the Charlie Hebdo attack, thus presenting a case of argumentation in context. The analysis focuses on the argumentative structure and on the rhetorical strategies that trigger emotional inferencing. The emotional inferencing derives from a Locus (...) of Ontological Implication, which links a situation and an emotion, while the culture-bound elements tend to be part of the endoxon. (shrink)

The concept of erotetic argument is introduced. Two relations between sets of declarative sentences and questions are analysed; and two classes of erotetic arguments are characterized.

This article focuses on the development of argumentation studies in France and their complex relations with discourse analysis. First, the meanings of the basic word `argument' in French and in American English are discussed and contrasted. Second, a brief historical section summarizes the complex history of rhetorical argumentation in France up until the late 1980s and the Perelmanian revival. Third, Grize `natural logic' and Anscombre and Ducrot `argumentation within language' are briefly discussed from the discourse analysis point of (...) view. These programmes have restored argumentation study to favour in France, where it is currently the research paradigm most referred to in recent work. The fourth section examines the present situation in France which is characterized by a strong new interest in argumentation in all disciplines; this is fuelling a tendency towards the use of argumentation theories — classical or modern — for practical, short-term analysis purposes. Fifth, a proposal is made for a better integration of argumentation studies in discourse analysis, based on the conception of argumentation as opposite points of view, either in face-to-face disputes or in written arguments, sometimes lasting for several centuries. This article is based on the premise that research into the history of rhetoric and argumentation, as well as in specific discourse analytic trends that emerged in France during the 1970s, has some permanent value in that a better understanding of an academic discipline's historical development can be a good introduction to its current problems. (shrink)

We perform a frequency analysis of the EPR-Bell argumentation. One of the main consequences of our investigation is that the existence of probability distributions of the Kolmogorov-type which was supposed by some authors is a mathematical assumption which may not be supported by actual physical quantum processes. In fact, frequencies for hidden variables for quantum particles and measurement devices may fluctuate from run to run of an experiment. These fluctuations of frequencies for micro-parameters need not contradict to the stabilization (...) of frequencies for physical observables. If, nevertheless, micro-parameters are also statistically stable, then violations of Bell's inequality and its generalizations may be a consequence of dependence of collectives corresponding to two different measurement devices. Such a dependence implies the violation of the factorization rule for the simultaneous probability distribution. Formally this rule coincides with the well known BCHS locality condition (or outcome independence condition). However, the frequency approach implies totally different interpretation of dependence. It is not dependence of events, but it is dependence of collectives. Such a dependence may be induced by the same preparation procedure. (shrink)

Empirical insights into language processing have a philosophical relevance that extends well beyond philosophical questions about language. This chapter will discuss this wider relevance: We will consider how experimental philosophers can examine language processing in order to address questions in several different areas of philosophy. To do so, we will present the emerging research program of experimental argument analysis (EAA) that examines how automatic language processing shapes verbal reasoning – including philosophical arguments. The evidential strand of experimental philosophy uses (...) mainly questionnaire-based methods to assess the evidentiary value of intuitive judgments that are adduced as evidence for philosophical theories and as premises for philosophical arguments. Extending this prominent strand of experimental philosophy, EAA underpins such assessments, extends the scope of the assessments, and expands the range of the empirical methods employed: EAA examines how automatic inferences that are continually made in language comprehension and production shape verbal reasoning, and draws on findings about comprehension biases that affect the contextualisation of such default inferences, in order to explain and expose fallacies. It deploys findings to assess premises and inferences from premises to conclusions, in philosophical arguments. To do so, it adapts methods from psycholinguistics and recruits methods from computational linguistics. (shrink)

China has a longstanding tradition of stressing the values of harmony and coherence, and Chinese society has often been portrayed as a culture in which conflict avoidance is viewed more positively than direct confrontation and argumentation. In order to evaluate the validity of this claim, this paper sketches Chinese people’s feelings and understandings about interpersonal arguing by reporting results of a data collection in China, using measures of argumentativeness, verbal aggressiveness, argument frames, and personalization of conflict. These results were compared (...) to those from a US sample. Chinese and US data differed in complex ways, but did not show Chinese respondents to be more avoidant. The Chinese correlations among variables were a reasonable match to expectations based on Western argumentation theories, although they did not replicate the US results precisely. The paper offers evidence that Chinese respondents had a more sophisticated understanding of interpersonal arguing than their US counterparts, and were more sensitive to the constructive possibilities of face-to-face disagreement. (shrink)

Do ubiquitous modes of thought (types of analysis, types of argumentation) pervade the entire corpus of the Rabbinic writings of late antiquity and impart coherence to those diverse documents? Here are the results of a systematic probe of representative Halakhic and Aggadic documents in search of the answer to that question. The result is limited but one-sided: the answer is yes, they do. The inquiry proves urgent, because the bases for supposing the Rabbinic documents coalesce have diminished, and the (...) differences between and among the respective documents have made their mark. The book asks whether, however diverse, all of the documents conform to a single, determinate program of [1] analysis and [2] argumentation. Do they raise in common a set of questions that are ubiquitous, and do they pursue a uniform inquiry, whatever the data subject to study? Further, does a single protocol of argumentation dictate the means by which analytical propositions are advanced and tested? If they do, then Rabbinic Judaism finds coherence in shared intellectual traits. These, then, would serve to define the foundations for the construction of all components into the Rabbinic system and structure. (shrink)

The goal of this study is to examine the argumentative functions of concessive yes, but… constructions. Based on interview transcripts, we examine the ways environmental activists negotiate their agreements and disagreements over climate change through yes, but… constructions. Starting from conversational analyses of such concessive sequences, we develop an account grounded in argumentative discourse analysis, notably pragma-dialectics. The analysis focuses on how in conceding arguments speakers re-present others’ discourse, what types of criticism they exercise through particular (...) sequential patterns and which argumentative techniques they saliently use. We show in particular that, in disputing the standpoints supported by the complex argumentation they encounter, speakers raise different types of criticism. We discuss how examining not only the sequencing of agreements and disagreements, but also the argumentative relations that generate these, may extend our understanding of such concessive constructions. (shrink)

The paper outlines a conceptual framework for the critical assessment of argumentation which differs in some of its core characteristics from conventional approaches: it is resolutely semantic rather than formal in its method; it centers on obligations rather than beliefs; and its analytical focus is on the contingent necessity of conclusions, rather than on their persuasiveness or formal validity. The paper briefly illustrates the applications of this conceptual framework by reanalyzing a couple of examples taken from the argumentation analysis (...) literature. (shrink)

In this article, the theory of argumentation set out by the Dutch scholars Frans van Eemeren and Rob Grootendorst is brought to bear in subjecting the general form of the argument from coherence to a critical analysis. First, a distinction is brought out between two basic kinds of argument from coherence: in one use this argumentative structure occurs as a sequence of two arguments establishing that a standpoint constitutes a particular instantiation or a inherent quality of the system (...) it will become part of (symptomatic argument); in the other use we have a main symptomatic argument supported by a subordinate argument appealing to instrumental considerations (pragmatic argument). It is then claimed that arguments from coherence are complex types of argumentation, structured at various argumentative levels, where the premises must be taken together to yield an adequate defence of the conclusion (coordinative argumentation). Finally, an evaluative assessment is made as to whether arguments from coherence can serve acceptably as tools for settling disputes: it will be maintained that we can generally welcome these argumentative structures as sound and fully acceptable provided we are aware of the interpretive discretion their use entails. (shrink)

Frege's views regarding analysis and synomymy have long been the subject of critical discussion. Some commentators, led by Dummett, have argued that Frege was committed to the view that each thought admits of a unique ultimate analysis. However, this interpretation is in apparent conflict with Frege's criterion of synonymy, according to which two sentence express the same thought if one cannot understand them without regarding them as having the same truth–value. In a recent article in this journal, Drai (...) attempts to reconcile Frege's criterion of synonymy with unique ultimate analysis by holding that, for Frege, if two sentences satisfy the criterion without being intensionally isomorphic, at most one of them is a privileged representation of the thought expressed. I argue that this proposal fails, because it conflicts not only with Frege's views of abstraction principles but also with slingshot arguments (including one presented by Drai herself) that accurately reflect Frege's commitment to the view that sentences alike in truth–value have the same Bedeutung. While Drai helpfully connects Frege's views of abstraction principles with such slingshot arguments, this connection cannot become fully clear until we recognise that Frege rejects unique ultimate analysis. (shrink)

Legal analysis is dominated by legal arguments, and the assessment of any legal claim requires the assessment of the strengths and weaknesses of those arguments. The ‘logocratic’ method is a systematic method for assessing the strengths and weaknesses of arguments. More specifically, it is a method designed to help the analyst determine what degree of warrant the premises of an argument provide for its conclusion. Although the method is applicable to any type of argument, this essay focuses on the (...) logocratic framework for assessing the strengths and weaknesses of evidentiary legal arguments, arguments offered in litigation in which evidentiary propositions are proffered to support hypotheses. The focus is on American law, but the logocratic analysis offered here could be adjusted without much trouble to handle arguments about evidence in other systems of litigation. In any legal system that aspires to have a fact-finding process that is sufficiently reliable to meet the requirements of justice, we might fashion an analogue for the Socratic maxim ‘the unexamined life is not worth living’: the unexamined evidentiary argument is not worth believing. The logocratic method seeks to help the evidence analyst pursue that Socratic mission, tailored to the rules and institutions of evidence law. (shrink)

Is there any justification for the common practice of allocating expensive medical resources to rescue a few from rare diseases, when those resources could be used to treat devastating diseases that affect the many? Does the use of Prozac and other anti-depressants make us inauthentic beings? Is it immoral and irrational to have children? What is the force of examples and counterexamples in bioethics? What are the relevance of moral intuition and the role of empirical evidence in bioethical argument? What (...) notion of “function” underlies accounts of the distinction between normality and disease and between therapy and enhancement? Is there an inherent conflict between research aimed at therapy and research aimed at gaining knowledge, such that the very notion of “therapeutic research” is an oxymoron? The twenty-one chapters in this volume strive, through the use of high quality argument and analysis, to get a good deal clearer concerning a range of issues _in _bioethics, and a range of issues_ about _bioethics. The essays are provocative, indeed, some quite radical and disturbing, as they call into question many common methodological and substantive assumptions in bioethics. (shrink)

This paper proposes a methodological synthesis in order to study multimodal media discourse and argumentation in the context of the so-called ‘refugee crisis’ in Greece. It follows the framework of Multimodal Critical Discourse Analysis, integrating this with argumentation studies, with a particular emphasis on the analysis of inference. Our data come from the Greek newspapers Kathimerini and Ta Nea. We contend that the proposed methodological synergy enables scrutiny of (a) racist conceptualizations cultivated by the representation of migrants and (...) refugees in headlines and photographs in newspaper articles along with (b) the argumentative potential that is implicitly sustained in these multimodal representations. (shrink)

This paper discusses idiomatic expressions like ‘that says it all’, ‘that says a lot’ etc. when used in presenting an argument. These expressions are instantiations of the grammatical pattern that says Q, in which Q is an indefinite quantifying expression. By making use of the pragma-dialectical theory of argumentation and the linguistic theory of construction grammar it is argued that instantiations of that says Q expressing positive polarity can fulfil the role of an argumentation’s linking premise. Furthermore, an analysis (...) of these expressions as presentational devices shows that an arguer can use them for strategic reasons, i.e. to leave the exact formulation of the standpoint implicit and to present the argument as self-evident. Using these devices derails into fallaciousness when the context offers insufficient clues to reconstruct the standpoint or when the argument does not offer the kind of support that would be required by the specific instantiation of Q. The argumentative function of instantiations of that says Q expressing negative polarity is that an antagonist can use them to attack the justificatory power of the protagonist’s argument. (shrink)

Both Lakoff and Johnson (1980) and Vervaeke and Kennedy (1996), in their critique of Lakoff and Johnson, drew narrowly from a broad range of reasonable interpretations of the metaphors they analyzed. Expanding the interpretations vitiates many of Vervaeke and Kennedy's criticisms, but it supports their call for an open interpretation of groups of metaphors and points toward a more complex elaboration of the theories put forth by Lakoff and Johnson. The results of applying this approach to "ARGUMENT IS WAR" suggest (...) that war is not necessarily the primary conceptual metaphor for contentious argument, as Lakoff and Johnson claimed. Rather, there is a complex field of contentious interactions, ranging from simple discussions through contests to all-out war: Any and all of these can be and are used as metaphors for the others. When a word or phrase like "defend," "position," "maneuver," or "strategy" is used, there is no a priori way to determine whether the intended meaning is an athletic contest or a game of chess. Similar analyses are applied to other examples from the metaphor literature, and a modification of the basic idea of conceptual mapping is proposed, in which metaphors map cognitive responses onto prototypical situations rather than mapping 1 specific experience or concept onto another. (shrink)

General practice consultation has often been characterized by pragma-dialecticians as an argumentative activity type. These characterizations are typically derived from theoretical insights and qualitative analyses. Yet, descriptions that are based on quantitative data are thus far lacking. This paper provides a detailed account of the development of an instrument to guide the quantitative analysis of argumentation in doctor–patient consultation. It describes the implementation and preliminary results of a content analysis of seventy videotaped medical consultations of which the (...) extent and type of doctors’ argumentative support for medical opinions and advice are analyzed. Based on the study results, this paper addresses the merits of observational studies using content analysis as a method for the analysis of argumentative discourse in context as well as some of its key challenges and limitations, laying bare the opportunities for future research. (shrink)

The principle-based approach is a methodology to classify and analyse argumentation semantics. In this paper we classify seven of the main alternatives for argumentation semantics using a set of new robustness principles. These principles complement Baroni and Giacomin’s original classification and deal with the behaviour of a semantics when the argumentation framework changes due to the addition or removal of an attack between two arguments. We distinguish so-called persistence principles and monotonicity principles, where the former deal with the question of (...) whether a labelling or extension of an argumentation framework under a given semantics persists after a change, and the latter with the question of whether new labellings or extensions are created after a change. We furthermore show in which sense labelling-based and extension-based semantics lead to subtly different principles and results. Our results can be used for choosing a semantics for a particular application, or to guide the search for new argumentation semantics, but they have been used also in the design of algorithms. (shrink)