Develops a logical analysis of dialogue in which two or more parties attempt to advance their own interests. It includes a classification of the major types of dialogues and a discussion of several important informal fallacies.

This book identifies 25 argumentation schemes for presumptive reasoning and matches a set of critical questions to each.

Fundamentals of Critical Argumentation presents the basic tools for the identification, analysis, and evaluation of common arguments for beginners. The book teaches by using examples of arguments in dialogues, both in the text itself and in the exercises. Examples of controversial legal, political, and ethical arguments are analyzed. Illustrating the most common kinds of arguments, the book also explains how to evaluate each kind by critical questioning. Douglas Walton shows how arguments can be reasonable under the right dialogue conditions by (...) using critical questions to evaluate them. The book teaches by example, both in the text itself and in exercises, but it is based on methods that have been developed through the author's thirty years of research in argumentation studies. (shrink)

A new pragmatic approach, based on the latest developments in argumentation theory, analyzing appeal to expert opinion as a form of argument. Reliance on authority has always been a common recourse in argumentation, perhaps never more so than today in our highly technological society when knowledge has become so specialized—as manifested, for instance, in the frequent appearance of "expert witnesses" in courtrooms. When is an appeal to the opinion of an expert a reasonable type of argument to make, and when (...) does it become a fallacy? This book provides a method for the evaluation of these appeals in everyday argumentation. Specialized domains of knowledge such as science, medicine, law, and government policy have gradually taken over as the basis on which many of our rational decisions are made daily. Consequently, appeal to expert opinion in these areas has become a powerful type of argument. Challenging an argument based on expert scientific opinion, for example, has become as difficult as it once was to question religious authority. Walton stresses that even in cases where expert opinion is divided, the effect of it can still be so powerful that it overwhelms an individual's ability to make a decision based on personal deliberation of what is right or wrong in a given situation. The book identifies the requirements that make an appeal to expert opinion a reasonable or unreasonable argument. Walton's new pragmatic approach analyzes that appeal as a distinctive form of argument, with an accompanying set of appropriate critical questions matching the form. Throughout the book, a historical survey of the key developments in the evolution of the argument from authority, dating from the time of the ancients, is given, and new light is shed on current problems of "junk science" and battles between experts in legal argumentation. (shrink)

William Baird collection in Social Sciences is the gift of the Estate of William Cameron Baird.

This is an introductory guidebook to the basic principles of how to construct good arguments and how to criticeze bad ones. It is non-technical in its approach and is based on 150 key examples, each discussed and evaluated in clear, illustrative detail. Professor Walton, a leading authority in the field of informal logic, explains how errors, fallacies, and other key failures of argument occur. He shows how correct uses of argument are based on sound strategies for reasoned persuasion and critical (...) responses. Among the many subjects covered are: forms of valid argument, relevance, appeals to emotion, personal attack, uses and abuses of expert opinion, problems in deploying statistics, loading terms, equivocation, arguments from analogy, and techniques of posing, replying to, and criticizing questions. The book will be ideally suited to courses in informal logic and in the introduction to philosophy. It will also prove valuable to studetns of pragmatics, rhetoric, and speech communication. (shrink)

Appeals to emotion—pity, fear, popular sentiment, and _ad hominem_ attacks—are commonly used in argumentation. Instead of dismissing these appeals as fallacious wherever they occur, as many do, Walton urges that each use be judged on its merits. He distinguished three main categories of evaluation. First, is it reasonable, even if not conclusive, as an argument? Second, is it weak and therefore open to critical questioning for argument? And third, is it fallacious? The third category is a strong charge that incurs (...) a critical burden to back it up by citing evidence from the given text and context of dialogue. Walton uses fifty-six case studies to demonstrate that the problem of emotional fallacies is much subtler than has been previously believed. Ranging over commercial advertisements, political debates, union-management negotiations, and ethical disputes, the case studies reveal that these four types of appeals, while based on presumptive reasoning that are tentative and subject to default, are not always or necessarily fallacious types of argumentation. (shrink)

Second edition of the introductory guidebook to the basic principles of constructing sound arguments and criticising bad ones. Non-technical in approach, it is based on 186 examples, which Douglas Walton, a leading authority in the field of informal logic, discusses and evaluates in clear, illustrative detail. Walton explains how errors, fallacies, and other key failures of argument occur. He shows how correct uses of argument are based on sound strategies for reasoned persuasion and critical responses. This edition takes into account (...) many developments in the field of argumentation study that have occurred since 1989, many created by the author. Drawing on these developments, Walton includes and analyzes 36 new topical examples and also brings in work on argumentation schemes. Ideally suited for use in courses in informal logic and introduction to philosophy, this book will also be valuable to students of pragmatics, rhetoric, and speech communication. (shrink)

A "slippery slope argument" is a type of argument in which a first step is taken and a series of inextricable consequences follow, ultimately leading to a disastrous outcome. Many textbooks on informal logic and critical thinking treat the slippery slope argument as a fallacy. Walton argues that used correctly in some cases, they can be a reasonable type of argument to shift a burden of proof in a critical discussion, while in other cases they are used incorrectly. Walton identifies (...) and analyzes four types of slippery slope argument. Walton presents guidelines that show how each type of slippery slope argument can be used correctly or incorrectly, using over fifty case studies of argumentation on controversial issues. These include abortion, medical research on human embryos, euthanasia, the decriminalization of marijuana, pornography, and censorship, and banning of American flag burning. (shrink)

In redefining logic, philosophers need to go back to the Aristotelian roots of the subject, to expand the boundaries of the subject to include informal logic and to give up false oppositions between informal and formal logic.

A leading expert in informal logic, Douglas Walton turns his attention in this new book to how reasoning operates in trials and other legal contexts, with special emphasis on the law of evidence. The new model he develops, drawing on methods of argumentation theory that are gaining wide acceptance in computing fields like artificial intelligence, can be used to identify, analyze, and evaluate specific types of legal argument. In contrast with approaches that rely on deductive and inductive logic and rule (...) out many common types of argument as fallacious, Walton’s aim is to provide a more expansive view of what can be considered "reasonable" in legal argument when it is construed as a dynamic, rule-governed, and goal-directed conversation. This dialogical model gives new meaning to the key notions of relevance and probative weight, with the latter analyzed in terms of pragmatic criteria for what constitutes plausible evidence rather than truth. (shrink)

This book offers a new theory of begging the question as an informal fallacy, within a pragmatic framework of reasoned dialogue as a normative theory of critical argumentation. The fallacy of begging the question is analyzed as a systematic tactic to evade fulfillment of a legitimate burden of proof by the proponent of an argument. The technique uses a circular structure of argument to block the further progress of dialogue and, in particular, the capability of the respondent to ask legitimate (...) critical questions in reply to the argument. Walton analyzes the concept of burden of proof in argument, and provides chapters on the use of argument diagramming as a technique of argument reconstruction. This powerful method of argument analysis developed therein is then applied to more than 100 case studies of circular argumentation where the charge of begging the question is or has been thought to be an appropriate criticism. Throughout this work, Walton throws light on the relationship between the problem of circular reasoning and broader issues in the critical analysis of argumentation. Ground-breaking use is made of the pragmatic theory of argument as interactive dialogue. Rules for several kinds of dialogue framework provide standards of good reasoning to validate or to refute the criticism that a particular argument begs the question. This book is directed to students and professionals in the fields of speech communication, philosophy, linguistics, logic, dispute mediation, and education. (shrink)

_Arguments from Ignorance _explores the situations in which the argument from ignorance functions as a respectable form of reasoning and those in which it is indeed fallacious. Douglas Walton draws on everyday conversations on all kinds of practical matters in which the _argumentum ad ignorantiam _is used quite appropriately to infer conclusions. He also discusses the inappropriate use of this kind of argument, referring to various major case studies, including the Salem witchcraft trials, the McCarthy hearings, and the Alger Hiss (...) case. This book makes an original contribution in the areas of argumentation theory and informal logic, contending that, despite its traditional classification as a fallacy, the argument from ignorance is a genuine, very common, and legitimate type of argumentation with an identifiable structure. But the book is also interdisciplinary in scope, explaining many widely interesting and controversial subjects in artificial intelligence, medical education, philosophy of science, and philosophy of law in a clear way that makes it accessible to a broad range of readers. (shrink)

This book provides a practical and accessible way of evaluating good and bad arguments used in everyday conversations by applying normative models of dialectical (interactive) argumentation, where two parties reason together in an orderly and cooperative way. Using case studies, the author analyzes correct and incorrect uses of argumentation on controversial issues that engage the reader's interest while illustrating points in a practical way. Walton gives clear explanations of the most common errors and tricky deceptions -- traditionally called "fallacies" -- (...) that can trip up an unwary arguer. (shrink)

Vol. presents a method for critically evaluating relevance in arguments based on case studies & a new relevance theory incorporating techniques of argumentation theory, logic & artificiaI intelligence. For scholars/students in argumentation & rhetoric.

Argumentation, which can be abstractly defined as the interaction of different arguments for and against some conclusion, is an important skill to learn for everyday life, law, science, politics and business. The best way to learn it is to try it out on real instances of arguments found in everyday conversational exchanges and legal argumentation. The introductory chapter of this book gives a clear general idea of what the methods of argumentation are and how they work as tools that can (...) be used to analyze arguments. Each subsequent chapter then applies these methods to a leading problem of argumentation. Today the field of computing has embraced argumentation as a paradigm for research in artificial intelligence and multi-agent systems. Another purpose of this book is to present and refine tools and techniques from computing as components of the methods that can be handily used by scholars in other fields. (shrink)

The paper considers contemporary models of presumption in terms of their ability to contribute to a working theory of presumption for argumentation. Beginning with the Whatelian model, we consider its contemporary developments and alternatives, as proposed by Sidgwick, Kauffeld, Cronkhite, Rescher, Walton, Freeman, Ullmann-Margalit, and Hansen. Based on these accounts, we present a picture of presumptions characterized by their nature, function, foundation and force. On our account, presumption is a modal status that is attached to a claim and has the (...) effect of shifting, in a dialogue, a burden of proof set at a local level. Presumptions can be analysed and evaluated inferentially as components of rule-based structures. Presumptions are defeasible, and the force of a presumption is a function of its normative foundation. This picture seeks to provide a framework to guide the development of specific theories of presumption. (shrink)

The basic question of this monograph is: how should we go about judging arguments to be reasonable or unreasonable? Our concern will be with argument in a broad sense, with realistic arguments in natural language. The basic object will be to engage in a normative study of determining what factors, standards, or procedures should be adopted or appealed to in evaluating an argument as "good," "not-so-good," "open to criticism," "fallacious," and so forth. Hence our primary concern will be with the (...) problems of how to criticize an argument, and when a criticism is reasonably justified. (shrink)

Media argumentation is a powerful force in our lives. From political speeches to television commercials to war propaganda, it can effectively mobilize political action, influence the public, and market products. This book presents a new and systematic way of thinking about the influence of mass media in our lives, showing the intersection of media sources with argumentation theory, informal logic, computational theory, and theories of persuasion. Using a variety of case studies that represent arguments that typically occur in the mass (...) media, Douglas Walton demonstrates how tools recently developed in argumentation theory can be usefully applied to the identification, analysis, and evaluation of media arguments. He draws upon the most recent developments in artificial intelligence, including dialogical theories of argument, which he developed, as well as speech act theory. Each chapter presents solutions to problems central to understanding, analyzing, and criticizing media argumentation. (shrink)

Recent work in artificial intelligence has increasingly turned to argumentation as a rich, interdisciplinary area of research that can provide new methods related to evidence and reasoning in the area of law. Douglas Walton provides an introduction to basic concepts, tools and methods in argumentation theory and artificial intelligence as applied to the analysis and evaluation of witness testimony. He shows how witness testimony is by its nature inherently fallible and sometimes subject to disastrous failures. At the same time such (...) testimony can provide evidence that is not only necessary but inherently reasonable for logically guiding legal experts to accept or reject a claim. Walton shows how to overcome the traditional disdain for witness testimony as a type of evidence shown by logical positivists, and the views of trial sceptics who doubt that trial rules deal with witness testimony in a way that yields a rational decision-making process. (shrink)

It is a longstanding if not altogether coherent tradition of logic and rhetorical studies that an argument can be incorrect or fallacious in virtue of some ...

Douglas N. Walton considers the question of whether the conventions of informal conversation can be articulated more precisely than they are at present. Specifically, he addresses the problem of the fallacy of ad hominem argumentation as it occurs in natural settings. Can rules be formulated to determine if criticisms of apparent hypocrisy in an argument are defensible or refutable? Walton suggests that they can, and ultimately defends the thesis that ad hominem reasoning is not fallacious per se. He carries his (...) analysis to the core of action--theoretic reasoning--by examining a number of specimen arguments. As suggested by the title, the conclusion of ad hominem argument is demonstrated to be relative to the arguer's position. In the appendixes of the book, articles by Gerald McAuliffe and Gordon R. Lowe illustrate vivid and powerful cases in which Walton's contentions are put to the test. (shrink)

A general outline of a theory of reasoned dialogue is presented as an underlying basis of critical analysis of a text of argument discourse. This theory is applied to the analysis of informal fallacies by showing how textual evidence can be brought to bear in argument reconstruction. Several basic types of dialogue are identified and described, but the persuasive type of dialogue is emphasized as being of key importance to critical thinking theory.

This book is an analysis of the distinctive form of reasoning, called practical reasoning by Aristotle (as opposed to theoretical reasoning), that serves to guide behaviour.

The aim of this paper is to make it clear how and why begging the question should be seen as a pragmatic fallacy which can only be properly evaluated in a context of dialogue. Included in the paper is a review of the contemporary literature on begging the question that shows the gradual emergence over the past twenty years or so of the dialectical conception of this fallacy. A second aim of the paper is to investigate a number of general (...) problems raised by the pragmatic framework. (shrink)

Reasoning from negative evidence takes place where an expected outcome is tested for, and when it is not found, a conclusion is drawn based on the significance of the failure to find it. By using Gricean maxims and implicatures, we show how a set of alternatives, which we call a paradigm, provides the deep inferential structure on which reasoning from lack of evidence is based. We show that the strength of reasoning from negative evidence depends on how the arguer defines (...) his conclusion and what he considers to be in the paradigm of negated alternatives. If we negate only two of the several possible alternatives, even if they are the most probable, the conclusion will be weak. However, if we deny all possible alternatives, the reasoning will be strong, and even in some cases deductively valid. (shrink)

Walton's book is a study of several fallacies in informal logic. Focusing on question-answer dialogues, and committed to a pragmatic rather than a semantic approach, he attempts to generate criteria for evaluating good and bad questions and answers. The book contains a discussion of such well-recognized fallacies as many questions, black-or-white questions, loaded questions, circular arguments, question-begging assertions and epithets, ad hominem and tu quoque arguments, ignoratio elenchi, and replying to a question with a question. In addition, Walton develops several (...) artificial dialogue games and has an excellent discussion of burden of proof in nonlegal contexts. The discussion is for the most part nontechnical and does not presuppose any training in formal logic. It is illustrated with many (sometimes overlong) examples of fallacies drawn from real life--mostly debates in the Canadian House of Commons. . . . Walton's book breaks new ground on a number of issues. Choice This first full-length study of logical fallacies, errors, faults, illicit attacks, blunders, and other critical deficiencies in interrogation and reply has been written in the tradition of informal fallacies in logic. It is especially valuable, readable, and interesting because of the 139 case studies it presents, many of these case studies come from political debates and some from interviews, legal cross-examinations, and other sources. Walton uses these challenging examples of tricky, aggressive, argumentative, or fallacious questions to develop coherent and pragmatic guidelines for criticizing questionable questions (and in some cases their replies) on logical grounds. Among the types of problematic questions analyzed are: the traditional so-called fallacy of many questions, illustrated by the famous Have you stopped beating your wife?; black and white questions; terminologically loaded questions; and questions containing personal attacks. These and other types of problematic questions as well as evasive replies and replying to a question with a question are studied. Critical errors of reasoning are identified and analyzed by developing context-based, normative models of reasonable dialogue in which a questioner must have freedom to ask informative and probing questions, and the respondent must be constrained to give reasonably direct, not overly evasive answers. In this era of negative and evasive political campaigning, with candidates employing skillful tactics of manipulating public opinion to assure election rather than taking clear stands and seriously debating issues in an informed and sincere manner, Question-Reply Argumentation is especially relevant reading for those who take democracy seriously. The methods used reflect a significant shift from earlier semantically based theories to current pragmatic, dialogue-based models, and will be of interest to logicians and linguists. The volume's conclusions should challenge some current preconceptions. Recommended reading for courses in logic, speech communications, linguistics, philosophy of language, areas of political science relating to political discourse and debate, courses on questioning in cognitive psychology, and courses on critical thinking in education. (shrink)

Arguments from popular opinion have long been regarded with suspicion, and in most logic textbooks the _ad populum _argument is classified as a fallacy. Douglas Walton now asks whether this negative evaluation is always justified, particularly in a democratic system where decisions are based on majority opinion. In this insightful book, Walton maintains that there is a genuine type of argumentation based on commonly accepted opinions and presumptions that should represent a standard of rational decision-making on important issues, especially those (...) of a personal and political nature. He shows how to judge arguments based on appeals to popular opinion in a more balanced way, identifying eleven subtypes of the _ad populum_ argument and providing a pragmatic method to evaluate each of these types. Walton has examined dozens of logic texts and drawn on a wide range of literature to reveal the many uses and misuses of popular opinion. He contrasts the traditional discussion of _ad populum _in Greek rhetoric with recent textbook treatment, then contrasts these contemporary views with his own dialectical perspective in order to clarify often confused appeals to prejudice and appeals to common knowledge. Although appeal to popular opinion has long been a powerful argumentative tactic, this is the first book to systematically describe and evaluate it as a well-defined type of argument with its own special characteristics. It enables us to deal with these often deceptive arguments in a critically balanced way and makes an original contribution to an important strand of rhetoric. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Philosophy and Rhetoric 34.2 (2001) 93-112 [Access article in PDF] Enthymemes, Common Knowledge, and Plausible Inference Douglas Walton The study of enthymemes has always been regarded as important in logic, critical thinking, and rhetoric, but too often it is the formal or mechanistic aspect of it that has been in the forefront. This investigation will show that there is a kind of plausibilistic script-based reasoning, of a kind that (...) has mainly been studied in artificial intelligence, that should have a much more important role to play in the study of enthymemes. But then curiously, as will also be shown, this plausibilistic type of reasoning was familiar in the ancient world, to the Sophists, as well as to leading philosophers such as Plato and Aristotle. By linking this ancient notion of plausibility to the modern notion used in computer science, this investigation reveals an important basis for the enthymeme that has a type of logical structure in its own right, but also has an informal aspect.An enthymeme, in current usage, is an argument that has one or more premises, or possibly a conclusion, not explicitly stated in the text, but that needs to have these propositions explicitly stated to extract the complete argument from the text. Sometimes enthymemes are described as arguments with "missing premises." That vocabulary is awkward, however, because the nonexplicit statement that needs to be added can be a conclusion, at least in a minority of cases. To make the exposition below smoother, the term nonexplicit assumption will be used to cover either the case of a nonexplicit premise or that of a nonexplicit conclusion. The problem with enthymemes is that if the nonexplicit assumptions in an argument are supposed to be propositions used by the arguer (as opposed to just the propositions needed to make the argument structurally correct, according to some standard), reasonable people can have differences of opinion on what the nonexplicit assumptions are supposed to be. The problem is that filling in the missing parts of enthymemes depends on interpreting the natural language [End Page 93] in which the argument was put forward to try to determine what the speaker meant to say.The solution to the problem comes through the recognition that enthymemes rest not only on formal (structural) criteria, but also on informal criteria. One of the most important of these informal criteria is something often called "common knowledge" (Govier 1992; Freeman 1995). But as shown below in a set of selected case studies of enthymemes, "common knowledge" is not really a kind of knowledge at all. It is really plausibility, or eikos, something well known in the ancient world and often misleadingly translated as "probability." Curiously, Aristotle's original doctrine of the enthymeme was based on this notion of plausibility. This historical fact has often been a source of puzzlement and confusion, and sometimes it has even been taken to indicate a defect or contradiction in Aristotle's treatment of the enthymeme. However, the goal of this investigation is not primarily historical. It is to work out one of the most important required steps toward a solution to the problem of enthymemes. But to do this, it is necessary to come back to the ancient notion of plausible inference. 1. The problem with enthymemes Once you have any formal theory of inference, like syllogistic, for example, you will be confronted by cases of arguments in everyday discourse that meet all the requirements for a structurally correct inference except that some part or parts, usually a premise or a conclusion, is missing. By "missing" is meant that the proposition in question has not been explicitly stated in the text of discourse, even though it may be clear enough that the speaker (writer) was relying on it, or including it, as part of the argument. The classic example is the following inference: All men are mortal; therefore, Socrates is mortal. To evaluate such an argument, surely some account of the "hidden" or "missing" assumption needs to be taken. The problem with enthymemes (Burke 1985; Gough and Tindale 1985; Hitchcock 1985) is that, if given carte... (shrink)

This paper presents a speech act analysis of presumption, using the framework of a dialogue in which two parties reason together. In the speech act of presumption, as opposed to that of assertion, the burden of proof resides not on the proponent to prove, but on the respondent to rebut. Some connections of this account with nonmonotonic reasoning and informal fallacies in argumentation are explored.

In response to the growing recognition of informal logic as a discipline in its own right, this collection of essays from leading contributors in the field provides the formative knowledge and historical context required to understand the development of a so far little studied subject area.

Argument invention is a method that can be used to help an arguer find arguments that could be used to prove a claim he needs to defend. The aim of this paper is to show how argumentation systems recently developed in artificial intelligence can be applied to the task of argument invention. One such system called Carneades is featured. Carneades can be used to analyze arguments, evaluate arguments, to make an argument diagram, and to construct arguments from a database. Using (...) some simple examples, the paper explains how Carneades works as a system of argument invention. (shrink)

This article outlines criteria for the evaluation of the argumentum ad hominem (argument against the person, or personal attack in argument) that is traditionally a part of the curriculum in informal logic. The argument is shown to be a kind of criticism which works by shifting the burden of proof in dialogue through citing a pragmatic inconsistency in an arguer's position. Several specific cases of ad hominem argumentation which pose interesting problems in analyzing this type of criticism are studied.

Bridging the gap between applied ethics and ethical theory, Ethical Argumentation draws on recent research in argumentation theory to develop a more realistic model of how ethical justification actually works.

This paper is a report of a pilot study of how candidates argue when they are running for political office. The election studied was the provincial election in Ontario, Canada, in the fall of 2011. Having collected about 250 arguments given during the election from newspaper media, we sought answers to the following questions, among others: which argumentation schemes have the greatest currency in political elections? Is a list of the best known argumentation schemes sufficient to classify the arguments given (...) in elections? What schemes should be added to the familiar list to make it more adequate for studying elections? Is it useful to classify arguments as being used for positive, policy-critical, person-critical and defensive purposes? Can political parties be usefully characterized by noting their preferred kinds of arguments and their most frequent uses of arguments? What lessons can be learned from this study to better design future studies of the same kind? (shrink)

This book provides an argumentation model for means-end reasoning, a distinctive type of reasoning used for problem-solving gand decision-making. Means-end reasoning is modeled as goal-directed argumentation from an agent's goals and known circumstances, and from an action selected as a means, to a decision to carry out the action. Goal-based reasoning for argumentation provides an argumentation model for this kind of reasoning, showing how it is employed in settings of intelligent deliberation where agents try to collectively arrive at a conclusion (...) on what they should do to move forward in a set of circumstances. The book explains how this argumentation model can help build more realistic computational systems of deliberation and decision-making and shows how such systems can be applied to solve problems posed by goal-based reasoning in numerous fields, from social psychology and sociology, to law, political science, anthropology, cognitive science, artificial intelligence, multi-agent systems, and robotics." -- Back cover. (shrink)

In this paper, a solution to the problem of analyzing burden of proof in argumentation is developed by building on the pioneering work of Erik C. W. Krabbe on metadialogues. Three classic cases of burden of proof disputes are analyzed, showing how metadialogue theory can solve the problems they pose. The solution is based on five dialectical requirements: (1) global burden of proof needs to be set at the confrontation stage of a dialogue, (2) there need to be special mechanisms (...) for resolving disputes about burden of proof at all four stages of the dialogue, (3) they are especially significant during the argumentation stage, where burden of proof often shifts back and forth at each move, (4) such local shifts need to be partly regulated by the global burden of proof already set, and (5) the connection between burden of proof and the speech act of making a presumption in a dialogue needs to be clarified. (shrink)