Douglas Walton’s work is extremely vast, multifaceted, and interdisciplinary. He developed theoretical proposals that have been used in disciplines that are not traditionally related to philosophy, such as law, education, discourse analysis, artificial intelligence, or medical communication. Through his papers and books, Walton redefined the boundaries not only of argumentation theory, but also logic and philosophy. He was a philosopher in the sense that his interest was developing theoretical models that can help explain reality, and more importantly interact with it. (...) For this reason, he proposed methods that have been used for analyzing different types of dialogical interactions, and modeling procedures for regulating them. (shrink)

In this talk I present the main results from Anta (2021), namely, that the theoretical division between Boltzmannian and Gibbsian statistical mechanics should be understood as a separation in the epistemic capabilities of this physical discipline. In particular, while from the Boltzmannian framework one can generate powerful explanations of thermal processes by appealing to their microdynamics, from the Gibbsian framework one can predict observable values in a computationally effective way. Finally, I argue that this statistical mechanical schism contradicts the Hempelian (...) (1958) thesis that the predictive power of a scientific theory is directly proportional to its explanatory potential, and vice versa. (shrink)

J. Anthony Blair is a prominent international figure in argumentation studies. He is among the originators of informal logic, an author of textbooks on the informal logic approach to argument analysis and evaluation and on critical thinking, and a founder and editor of the journal Informal Logic. Blair is widely recognized among the leaders in the field for contributing formative ideas to the argumentation literature of the last few decades. This selection of key works provides insights into the history of (...) the field of argumentation theory and various related disciplines. It illuminates the central debates and presents core ideas in four main areas: Critical Thinking, Informal Logic, Argument Theory and Logic, Dialectic and Rhetoric. (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.

The article develops and justifies, on the basis of the epistemological argumentation theory, two central pieces of the theory of evaluative argumentation interpretation: 1. criteria for recognizing argument types and 2. rules for adding reasons to create ideal arguments. Ad 1: The criteria for identifying argument types are a selection of essential elements from the definitions of the respective argument types. Ad 2: After presenting the general principles for adding reasons (benevolence, authenticity, immanence, optimization), heuristics are proposed for finding missing (...) reasons, for deductive arguments, e.g., semantic tableaux are suggested. (shrink)

An essential step to evaluating arguments is moving from the weight of individual premises to the weight of the conclusion. In order to perform this step, one must understand the relationship between the premises in the argument. In the past, analyzing premise relations in informal logic has been limited primarily to the linked-convergent distinction. This distinction has failed to resolve some of the basic problems in finding a definition because it has underestimated the degree to which premises interact with each (...) other in some complicated way. Embracing concepts from holistic epistemology, I argue that evaluating a premise involves considering a wide set of presuppositions and implications that that premise, if accepted, carries. I call this wide set the premise/world. The relationship between premises is then essentially just the relationship between these two premise/worlds. (shrink)

Wellman identified three types of conductive arguments, the third of which contains both pro and counter-considerations in the same piece of reasoning. This paper provides a pragma-dialectical analysis of this type of argumentation, with special focus on argumentation reconstruction. It argues that the account of pro/con argumentation in the framework of argument-as-product has problems solvable by a pragma-dialectical approach. The paper asserts that pro/con argumentation should be analyzed as a dialectical strategy of a protagonist, where acknowledgement of counter-considerations shows that (...) the antagonist’s reasons have been taken into consideration, although the pro-considerations override them. Thus, the pro-considerations of pro/con argumentation should be interpreted as the protagonist’s overriding defeaters of the antagonist’s counter-arguments, the protagonist incorporating the latter as counter-considerations. The paper further argues that the pragma-dialectical framework needs an additional conceptual tool to properly reconstruct complex forms of pro/con argumentation. Finally, the pragma-dialectical approach to reconstruct pro/con argumentation has several advantages, especially to a more logical-structural approach to complex pro/con argumentation. (shrink)

To illustrate the development of argumentation theory, the paper traces the journey of the pragma-dialectical theory as it widened its scope, step by step, from an abstract model of critical discussion to the complexities of actual argumentative discourse. It describes how, having contextualized, empiricalized and formalized their approach, pragma-dialecticians are now putting the theory’s analytical instruments to good use in identifying prototypical argumentative patterns in specific communicative activity types in the various communicative domains. This means that they can now start (...) answering the crucial question about the typical characteristics of their discourse asked by interested lawyers, politicians, academics and other practitioners of argumentation. (shrink)

Causal reasoning is one of our most central cognitive competencies, enabling us to adapt to our world. Causal knowledge allows us to predict future events, or diagnose the causes of observed facts. We plan actions and solve problems using knowledge about cause-effect relations. Without our ability to discover and empirically test causal theories, we would not have made progress in various empirical sciences. In the past decades, the important role of causal knowledge has been discovered in many areas of cognitive (...) psychology. Despite the ubiquity of causal reasoning, textbooks of cognitive psychology have neglected this growing field. The goal of The Oxford Handbook of Causal Reasoning is to fill this gap. The handbook brings together the leading researchers in the field of causal reasoning and offers state-of-the-art presentations of theories and research. It provides introductions of competing theories of causal reasoning, and discusses its role in various cognitive functions and domains. The final section presents research from neighboring fields. 1. Causal Reasoning: An Introduction Michael R. Waldmann Part I: Theories of Causal Cognition 2. Associative Accounts of Causal Cognition Mike E. Le Pelley, Oren Griffiths, and Tom Beesley 3. Rules of Causal Judgment: Mapping Statistical Information Onto Causal Beliefs José C. Perales, Andrés Catena, Antonio Cándido, and Antonio Maldonado 4. The Inferential Reasoning Theory of Causal Learning: Toward a Multi- Process Propositional Account Yannick Boddez, Jan De Houwer, and Tom Beckers 5. Causal Invariance as an Essential Constraint for Creating a Causal Representation of the World: Generalizing the Invariance of Causal Power Patricia W. Cheng and Hongjing Lu 6. The Acquisition and Use of Causal Structure Knowledge Benjamin Margolin Rottman 7. Formalizing Prior Knowledge in Causal Induction Thomas L. Griffiths 8. Causal Mechanisms Samuel G. B. Johnson and Woo-kyoung Ahn 9. Force Dynamics and Causation Phillip Wolff and Robert Thorstad 10. Mental Models and Causation P. N. Johnson- Laird and Sangeet S. Khemlani 11. Pseudocontingencies Klaus Fiedler and Florian Kutzner 12. Singular Causation David Danks 13. Cognitive Neuroscience of Causal Reasoning Joachim T. Operskalski and Aron K. Barbey Part II: Basic Cognitive Functions 14. Visual Impressions of Causality Peter White 15. Goal-Directed Actions Bernhard Hommel 16. Planning and Control Magda Osman 17. Reinforcement Learning and Causal Models Samuel J. Gershman 18. Causation and the Probability of Causal Conditionals David E. Over 19. Causal Models and Conditional Reasoning Mike Oaksford and Nick Chater 20. Concepts as Causal Models: Categorization Bob Rehder 21. Concepts as Causal Models: Induction Bob Rehder 22. Causal Explanation Tania Lombrozo and Nadya Vasilyeva 23. Diagnostic Reasoning Björn Meder and Ralf Mayrhofer 24. Inferring Causal Relations by Analogy Keith J. Holyoak and Hee-Seung Lee 25. Causal Argument Ulrike Hahn, Roland Bluhm, and Frank Zenker 26. Causality in Decision- Making York Hagmayer and Philip M. Fernbach Part III: Domains of Causal Reasoning 27. Intuitive Theories Tobias Gerstenberg and Joshua B. Tenenbaum 28. Space, Time, and Causality Marc J. Buehner 29. Causation in Legal and Moral Reasoning David A. Lagnado and Tobias Gerstenberg 30. The Role of Causal Knowledge in Reasoning About Mental Disorders Woo-kyoung Ahn, Nancy S. Kim, and Matthew S. Lebowitz 31. Causality and Causal Reasoning in Natural Language Torgrim Solstad and Oliver Bott 32. Social Attribution and Explanation Denis Hilton Part IV: Development, Phylogeny, and Culture 33. The Development of Causal Reasoning Paul Muentener and Elizabeth Bonawitz 34. Causal Reasoning in Non-Human Animals Christian Schloegl and Julia Fischer 35. Causal Cognition and Culture Andrea Bender, Sieghard Beller, and Douglas L. Medin. (shrink)

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

In this paper, I argue that, other things being equal, simpler arguments are better. In other words, I argue that, other things being equal, it is rational to prefer simpler arguments over less simple ones. I sketch three arguments in support of this claim: an argument from mathematical proofs, an argument from scientific theories, and an argument from the conjunction rule.

Is it possible for an argument to have either zero premises or an infinite number of premises? I shall argue that regardless of how you conceive of arguments you should accept that an argument could have an infinite number of premises. The zero case is more complicated since the matter seems to depend not only on the metaphysics of arguments, but also the nature and function of arguing. I shall argue that at least a plausible case can be made for (...) the possibility of zero premise arguments. (shrink)

If dialogue is a necessary condition for argument, argumentation in oratory becomes questionable, since rhetoric is not a dialogically structured activity. If special norms apply to the ‘solo’ performances of rhetoric, the orator’s activity may be more appropriately described as reasoning than as arguing. By analyzing in what respect rhetorical texts can be interpreted as dialogue-based and subject to criteria of Informal Logic, the virtues of rhetorical argumentation in contrast to logic and dialectic emerge.

Introduction: Clinical practice guidelines (CPGs) are an important source of justification for clinical decisions in modern evidence-based practice. Yet, we have given little attention to how they argue their evidence. In particular, how do CPGs argue for treatment with long-term medications that are increasingly prescribed to older patients? Approach and rationale: I selected six disease-specific guidelines recommending treatment with five of the medication classes most commonly prescribed for seniors in Ontario, Canada. I considered the stated aims of these CPGs and (...) the techniques employed towards those aims. Finally, I reconstructed and logically analysed the arguments supporting recommendations for pharmacotherapy. Analysis: The primary function of CPGs is rhetorical, or persuasive, and their means of persuasion include both a display of their credibility and their argumentation. Arguments supporting pharmacotherapy recommendations for the target population follow a common inductive pattern: statistical generalization from randomized controlled trial (RCT) and meta-analysis evidence. Two of the CPGs also argue their treatment recommendations for older patients in this style, while three fail to justify pharmacotherapy specifically for the older population. Discussion: The arguments analysed lack the auxiliary assumptions that would warrant making a generalization about the clinical effectiveness of medications for the older population. Guidelines reason using simple induction, while ignoring important inferential gaps. Future guidelines should aspire to be well-reasoned rather than simply evidence-based; argue from a plurality of evidence; be wary of hasty inductions; appropriately limit the scope of their recommendations; and avoid making law-like, prescriptive generalizations. (shrink)

In previous work I argued against (i) the likelihood of finding a theoretically sound foundation for the linked/convergent distinction and (ii) the utility of the distinction even if a sound theoretical basis could be found. Here I subject Douglas Walton’s comprehensive discussion of the linked/convergent distinction found in Argument Structure: A Pragmatic Theory to careful scrutiny and argue that at best Walton’s theory remains incomplete and that attempts to fill out the details will run afoul of at least one of (...) the problems adduced above—i.e., result in either a theoretically unsound distinction or a theoretically sound, but unnecessary distinction. (shrink)

In this overview article, we first explain what we take informal logic to be, discussing misconceptions and distinguishing our conception of it from competing ones; second, we briefly catalogue recent informal logic research, under 14 headings; third, we suggest four broad areas of problems and questions for future research; fourth, we describe current scholarly resources for informal logic; fifth, we discuss three implications of informal logic for philosophy in particular, and take note ofpractical consequences of a more general sort.

Quantitative apparatus for assessing strength of an argument was improved in the article. A probative generalisation and verification of the R.Yanal's algorithm to calculate convergent argument were proposed. The generalization obtained deals with both quantity (or number) and quality (or truth-values) of the argument's reasons.

We present a formal, mathematical model of argument structure and evaluation, taking seriously the procedural and dialogical aspects of argumentation. The model applies proof standards to determine the acceptability of statements on an issue-by-issue basis. The model uses different types of premises (ordinary premises, assumptions and exceptions) and information about the dialectical status of statements (stated, questioned, accepted or rejected) to allow the burden of proof to be allocated to the proponent or the respondent, as appropriate, for each premise separately. (...) Our approach allows the burden of proof for a premise to be assigned to a different party than the one who has the burden of proving the conclusion of the argument, and also to change the burden of proof or applicable proof standard as the dialogue progresses from stage to stage. Useful for modeling legal dialogues, the burden of production and burden of persuasion can be handled separately, with a different responsible party and applicable proof standard for each. Carneades enables critical questions of argumentation schemes to be modeled as additional premises, using premise types to capture the varying effect on the burden of proof of different kinds of questions. (shrink)

Even with the lack of consensus on the nature of an argument, the thesis that explanations and arguments are distinct is near orthodoxy in well-known critical thinking texts and in the more advanced argumentation literature. In this paper, I reconstruct two rationales for distinguishing arguments from explanations. According to one, arguments and explanations are essentially different things because they have different structures. According to the other, while some explanations and arguments may have the same structure, they are different things because (...) explanations are used for different purposes than arguments. I argue that both rationales fail to motivate a distinction between arguments and explanations. Since these are the only rationales for distinguishing arguments from explanations that I am prepared to take seriously, I don’t see why we should exclude explanations from being arguments. (shrink)

If an argument can be reconstructed in at least two different ways, then which reconstruction is to be preferred? In this paper I address this problem of argument reconstruction in terms of Ryle’s infinite regress argument against the view that knowledge-how requires knowledge-that. First, I demonstrate that Ryle’s initial statement of the argument does not fix its reconstruction as it admits two, structurally different reconstructions. On the basis of this case and infinite regress arguments generally, I defend a revisionary take (...) on argument reconstruction: argument reconstruction is mainly to be ruled by charity (viz. by general criteria which arguments have to fulfil in order to be good arguments) rather than interpretation. (shrink)

What are the historical origins of the argumentum ad consequentiam, the argument from consequences, sometimes featured as an informal fallacy in logic textbooks? As shown in this paper, knowledge of the argument can be traced back to Aristotle. And this type of argument shows a spotty history of recognition in logic texts and manuals over the centuries. But how it got into the modern logic textbooks as a fallacy remains somewhat obscure. Its modern genesis is traced to the logic text (...) of James McCosh. (shrink)

The paper's thesis is that dialogue is not an adequate model for all types of argument. The position of Walton is taken as the contrary view. The paper provides a set of descriptions of dialogues in which arguments feature in the order of the increasing complexity of the argument presentation at each turn of the dialogue, and argues that when arguments of great complexity are traded, the exchanges between arguers are turns of a dialogue only in an extended or metaphorical (...) sense. It argues that many of the properties of engaged back-and-forth exchanges of paradigmatic argument dialogues are not found in ‘solo’ arguments, and that at least some of the norms appropriate to the former type of argument, such as some of the pragma-dialectical rules of van Eemeren and Grootendorst's model, do not apply to the latter. (shrink)

This chapter focuses on alternative logics. It discusses a hierarchy of logical reform. It presents case studies that illustrate particular aspects of the logical revisionism discussed in the chapter. The first case study is of intuitionistic logic. The second case study turns to quantum logic, a system proposed on empirical grounds as a resolution of the antinomies of quantum mechanics. The third case study is concerned with systems of relevance logic, which have been the subject of an especially detailed reform (...) program. Finally, the fourth case study is paraconsistent logic, perhaps the most controversial of serious proposals. (shrink)

Current approaches used in educational research and practice to evaluate the quality of written arguments often rely on structural analysis. In such assessments, credit is awarded for the presence of structural elements of an argument, such as claims, evidence, and rebuttals. In this article, we discuss limitations of such approaches, including the absence of criteria for evaluating the quality of the argument elements. We then present an alternative framework, based on the Rational Force Model (RFM), which originated from the work (...) of a Nordic philosopher Næss. Using an example of an argumentative essay, we demonstrate the potential of the RFM to improve argument analysis by focusing on the acceptability and relevance of argument elements, two criteria widely considered to be fundamental markers of argument strength. We outline possibilities and challenges with using the RFM in educational contexts and conclude by proposing directions for future research. (shrink)

This paper presents a formalization of informal logic using the Carneades Argumentation System, a formal, computational model of argument that consists of a formal model of argument graphs and audiences. Conflicts between pro and con arguments are resolved using proof standards, such as preponderance of the evidence. Carneades also formalizes argumentation schemes. Schemes can be used to check whether a given argument instantiates the types of argument deemed normatively appropriate for the type of dialogue.

Deductivism is not merely a logical technique, but also a theory of normativity: it provides an objective and universal standard of evaluation. Contemporary dialectical logic rejects deductive normativity, replacing its universal standard by an intersubjective standard. It is argued in this paper that dialectical normativity does not improve upon deductive normativity. A dialogico-rhetorical alternative is proposed.

Informal logic began in the 1970s as a critique of then-current theoretical assumptions in the teaching of argument analysis and evaluation in philosophy departments in the U.S. and Canada. The last 35 years have seen significant developments in informal logic and critical thinking theory. The paper is a pilot study of the influence of these advances in theory on what is taught in courses on argument analysis and critical thinking in U.S. and Canadian philosophy departments. Its finding, provisional and much-qualified, (...) is that the theoretical developments and refinements have had limited impact on instruction in leading philosophy departments. (shrink)

This article concerns the structure of defeasible arguments like: 'If Bob has red spots, Bob has the measles; Bob has red spots; therefore Bob has the measles.' The issue is whether such arguments have the form of modus ponens or not. Either way there is a problem. If they don't have the form of modus ponens, the common opinion to the contrary taught in leading logic textbooks is wrong. But if they do have the form of modus ponens, doubts are (...) raised about the conventional dogma that all arguments having the form of modus ponens are deductively valid. By carefully examining arguments on both sides of the issue, reasonable doubts are raised about the view that all arguments having a modus ponens form are valid. (shrink)

Consider the proposition, "Informal logic is a subdiscipline of philosophy". The best chance of showing this to be true is showing that informal logic is part of logic, which in turn is a part of philosophy. Part 1 is given over to the task of sorting out these connections. If successful, informal logic can indeed be seen as part of philosophy; but there is no question of an exclusive relationship. Part 2 is a critical appraisal of the suggestion that informal (...) logic is applied epistemology. Part 3 examines the claim that informal logic has failed to penetrate into mainstream philosophy, and suggestions for amelioration are considered. (shrink)

In this paper, a survey is presented of the main approaches to the structure of argumentation. The paper starts with a historical overview of the distinctions between various types of argument structure. Next, the main definitions given in the various approaches are discussed as well as the methods that are proposed to deal with doubtful cases.

Numerous informal logi- cians and argumentation theorists restrict their theorizing to what they call “real” arguments. But is there a clear distinction to be made between “real” and “non-real” arguments? Here I explore four possible accounts of the alleged distinction and argue that none can serve the theoretical uses to which the distinction is most often put. Résumé: Plusieurs logiciens construction formels et théoriciens de l’argument- ation limitent leur non de théories à ce qu’ils appellent des arguments « authentiques ». (...) Mais y-a- t’il une distinction claire entre des arguments« authentiques » et « inau- thentiques » ? Ici j’explore quatre descriptions possibles de cette préten- due distinction et je soutiens qu’- aucune ne répond aux besoins théori- ques auxquels elles sont censées ré- pondre. (shrink)

This dissertation is on infinite regress arguments in philosophy. Its main goals are to explain what such arguments from many distinct philosophical debates have in common, and to provide guidelines for using and evaluating them. Two theories are reviewed: the Paradox Theory and the Failure Theory. According to the Paradox Theory, infinite regress arguments can be used to refute an existentially or universally quantified statement (e.g. to refute the statement that at least one discussion is settled, or the statement that (...) discussions are settled only if there is an agreed-upon criterion to settle them). According to the Failure Theory, infinite regress arguments can be used to demonstrate that a certain solution fails to solve an existentially or universally quantified problem (e.g. to demonstrate that a certain solution fails to settle all discussions, or that it fails to settle even one discussion). In the literature, the Paradox Theory is fairly well-developed, and this dissertation provides the Failure Theory with the same tools. (shrink)

An approach to argument macrostructure -- The dialectical nature of argument -- Toulmin's problematic notion of warrant -- The linked-convergent distinction, a first approximation -- Argument structure and disciplinary perspective : the linked-convergent versus multiple-co-ordinatively compound distinctions -- The linked-convergent distinction, refining the criterion -- Argument structure and enthymemes -- From analysis to evaluation.

Argumentation schemes are forms of reasoning that are fallible but correctable within a self-correcting framework. Their use provides a basis for taking rational action or for reasonably accepting a conclusion as a tentative hypothesis, but they are not deductively valid. We argue that teleological reasoning can provide the basis for justifying the use of argument schemes both in monological and dialogical reasoning. We consider how such a teleological justification, besides being inspired by the aim of directing a bounded cognizer to (...) true belief and correct choices, needs to take into account the attitudes of dialogue partners as well as normative models of dialogue and communicative activity types, in particular social and cultural settings. (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)

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.

Topical Themes in Argumentation Theory brings together twenty exploratory studies on important subjects of research in contemporary argumentation theory. The essays are based on papers that were presented at the 7th Conference of the International Society for the Study of Argumentation in Amsterdam in June 2010. They give an impression of the nature and the variety of the kind of research that has recently been carried out in the study of argumentation. The volume starts with three essays that provide stimulating (...) theoretical perspectives on argumentation. Subsequently, some views are explained on the intriguing topics of ‘dissensus’ and ‘deep disagreement’. After a discussion of three different approaches to the treatment of types of argumentation some classical themes from antique argumentation theory are revisited. The new research area of visual argumentation is explored in the next part. The volume concludes with three reports of experimental studies concerning argumentative discourse. The volume starts with three essays that provide stimulating theoretical perspectives on argumentation. Subsequently, some views are explained on the intriguing topics of ‘dissensus’ and ‘deep disagreement’. After a discussion of three different approaches to the treatment of types of argumentation some classical themes from antique argumentation theory are revisited. The new research area of visual argumentation is explored in the next part. The volume concludes with three reports of experimental studies concerning argumentative discourse. The volume starts with three essays that provide stimulating theoretical perspectives on argumentation. Subsequently, some views are explained on the intriguing topics of ‘dissensus’ and ‘deep disagreement’. After a discussion of three different approaches to the treatment of types of argumentation some classical themes from antique argumentation theory are revisited. The new research area of visual argumentation is explored in the next part. The volume concludes with three reports of experimental studies concerning argumentative discourse. (shrink)

The paper argues that metaphysical thought, or thought in whose context our general framework of sense is under scrutiny, involves, legitimates, and requires a variety of informal analogues of the ‘true contradictions’ supported in some paraconsistent formal logics. These are what we can call informal ‘legitimate logical inadequacies’. These paradoxical logical structures also occur in deeply pluralist contexts, where more than one, conflicting general framework for sense is relevant. The paper argues further that these legitimate logical inadequacies are real or (...) inherent in sense itself rather than conventional, shows how they can feature in argumentative practice in these metaphysical and pluralist contexts, and discusses some of their implications for metaphysical truth and for philosophical inquiry and disagreement. (shrink)

Douglas Walton has been right in calling us to attend to the pragmatics of argument. He has, however, also insisted that arguments should be understood and assessed by considering the functions they perform; and from this, I dissent. Argument has no determinable function in the sense Walton needs, and even if it did, that function would not ground norms for argumentative practice. As an alternative to a functional theory of argumentative pragmatics, I propose a design view, which draws attention to (...) the way participants strategically undertake and impose norms on themselves in order for their arguments to have force. (shrink)

Bipolar argument graphs represent the structure of complex pro and contra arguments for one or more standpoints. In this article, ampliative and exclusionary principles of evaluating argument strength in bipolar acyclic argumentation graphs are laid out and compared to each other. Argument chains, linked arguments, link attackers and supporters, and convergent arguments are discussed. The strength of conductive arguments is also addressed but it is argued that more work on this type of argument is needed to properly distinguish argument strength (...) from more general value-based components of such arguments. The overall conclusion of the article is that there is no justifiably unique solution to the problem of argument strength outside of a particular epistemological framework. (shrink)

We develop conceptions of arguments and of argument types that will, by serving as the basis for developing a natural classification of arguments, benefit work in artificial intelligence. Focusing only on arguments construed as the semantic entities that are the outcome of processes of reasoning, we outline and clarify our view that an argument is a proposition that represents a fact as both conveying some other fact and as doing so wholly. Further, we outline our view that, with respect to (...) arguments that are propositions, (roughly) two arguments are of the same type if and only if they represent the same relation of conveyance and do so in the same way. We then argue for our conceptions of arguments and argument types, and compare them to alternative positions. We also illustrate the need for, and some of the strengths of, our approach to classifying arguments through an examination of aspects of two prominent and recent attempts to classify arguments using argumentation schemes, namely those of M. Kienpointner and D. Walton. Finally, we clarify how our conception of arguments and of argument types can assist in developing an exhaustive classification of arguments. (shrink)

According to Douglas Walton, the concept of presumption relates to both logical and dialogical components. Logically, a presumption is the conclusion of a presumptive defeasible inference. Dialogically, the function of a presumptions to shift the burden of proof to the respondent in order to move the dialogue forward when the proponent, due to an objective lack of evidence, cannot present a sufficiently persuasive proposition. Presumptive status, assigned only at the argumentation stage of dialogue, is provisional: a particular presumption stands until (...) further counter-indications are found. This paper points out some possible difficulties pertaining to Walton’s dialogical model of presumption. Firstly, once a presumption's typical practical function is made precise, Walton’s idea of presumption starts to lose its conceptual cohesion, thereby becoming applicable in the opening stage of dialogue, as well. Secondly, cohesion is lost also in practical contexts, since Walton's "seat belts" example might indicate that presumptions are not evidentially defeasible if the practical stakes are raised high enough. Most importantly, contextual evaluation may reveal that presumptions do not shift the burden of proof in any specific or genuine way. (shrink)

The paper argues that the arguments from probability so popular in early Greek rhetoric and oratory essentially operate by appealing to common positions shared by both speaker and audience. Particularly in controversial debate provoked by fundamental dissensus they make their claim acceptable to the audience by pointing out a basic coherence or congruence of the speaker’s narrative with the audience’s own pre-established standards or standards of knowledge.

One popular test for distinguishing linked and convergent argument structures is Robert Yanal's Ordinary Summing Test. Douglas Walton, in his comprehensive survey of possible candidates for the linked/convergent distinction, advocates a particular version of Yanal's test. In a recent article, Alexander Tyaglo proposes to generalize and verifY Yanal's algorithm for convergent arguments, the basis for Yanal's Ordinary Summing Test. In this paper I will argue that Yanal's ordinary summing equation does not demarcate convergence and so his Ordinary Summing Test fails. (...) Hence, despite Walton's recommendation or Tyaglo's generalization, the Ordinary Summing Test should not be used for distinguishing linked argument structures from convergent argument structures. (shrink)

Robert Fogelin formulated the thesis “that deep disagreements cannot be resolved through the use of argument, for they undercut the conditions essential to arguing.” The possibility of arguing presupposes “a shared background of beliefs and preferences,” and if such a background is not given, there is no way of “rational” dispute resolution. By contrast to this pessimistic view, I will propose a method that has been developed to overcome difficulties as described by Fogelin.