ARGUING ON THE TOULMIN MODEL Argumentation Library 10 VOLUME Series Editors Frans H. van Eemeren, University of Amsterdam Scott Jacobs, University of Arizona Erik C.W. Krabbe, University of Groningen John Woods, University of Lethbridge ARGUING ON THE TOULMIN MODEL New Essays in Argument Analysis and Evaluation Edited by DAVID HITCHCOCK Mc Master University, Hamilton, Canada and BART VERHEIJ Rijksuniversiteit Groningen, Groningen, The Netherlands AC.I.P. Catalogue record for this book is available from the Library of Congress. ISBN-10 1-4020-4937-4 (HB) ISBN-13 978-1-4020-4937-4 (HB) ISBN-10 1-4020-4938-2 (e-book) ISBN-13 978-1-4020-4938-2 (e-book) Published by Springer, P.O. Box 17, 3300 AADordrecht, The Netherlands. www.springer.com Printed on acid-free paper All Rights Reserved © 2006 Springer No part of this work may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, microfilming, recording or otherwise, without written permission from the Publisher, with the exception of any material supplied specifically for the purpose of being entered and executed on a computer system, for exclusive use by the purchaser of the work. CONTENTS ACKNOWLEDGEMENTS VII 1 INTRODUCTION 1 David Hitchcock and Bart Verheij 2 REASONING IN THEORY AND PRACTICE 25 Stephen E. Toulmin 3 A CITATION-BASED REFLECTION ON TOULMIN AND ARGUMENT 31 Ronald P. Loui 4 COMPLEX CASES AND LEGITIMATION INFERENCE: EXTENDING THE TOULMIN MODEL TO DELIBERATIVE ARGUMENT IN CONTROVERSY 39 G. Thomas Goodnight 5 A METAMATHEMATICAL EXTENSION OF THE TOULMIN AGENDA 49 Mark Weinstein 6 TOULMIN’S MODEL OF ARGUMENT AND THE QUESTION OF RELATIVISM 71 Lilian Bermejo-Luque 7 SYSTEMATIZING TOULMIN’S WARRANTS: AN EPISTEMIC APPROACH 87 James B. Freeman 8 WARRANTING ARGUMENTS, THE VIRTUE OF VERB 103 James F. Klumpp 9 EVALUATING INFERENCES: THE NATURE AND ROLE OF WARRANTS 115 Robert C. Pinto 10 ‘PROBABLY’ 145 Robert H. Ennis 11 THE VOICE OF THE OTHER: A DIALOGICO-RHETORICAL UNDERSTANDING OF OPPONENT AND OF 1 65 TOULMIN’S REBUTTAL Wouter H. Slob 12 EVALUATING ARGUMENTS BASED ON TOULMIN’S SCHEME 181 Bart Verheij 13 GOOD REASONING ON THE TOULMIN MODEL 203 David Hitchcock V VI CONTENTS 14 THE FLUIDITY OF WARRANTS: USING THE TOULMIN MODEL TO ANALYSE PRACTICAL DISCOURSE 219 Olaf Tans 15 ARTIFICIAL INTELLIGENCE & LAW, LOGIC AND ARGUMENT SCHEMES 231 Henry Prakken 16 MULTIPLE WARRANTS IN PRACTICAL REASONING 247 Christian Kock 17 THE QUEST FOR RATIONALISM WITHOUT DOGMAS IN LEIBNIZ AND TOULMIN 261 Txetxu Ausín 18 FROM ARGUMENTS TO DECISIONS: EXTENDING THE TOULMIN VIEW 273 John Fox and Sanjay Modgil 19 USING TOULMIN ARGUMENTATION TO SUPPORT DISPUTE SETTLEMENT IN DISCRETIONARY DOMAINS 289 John Zeleznikow 20 TOULMIN’S MODEL AND THE SOLVING OF ILL-STRUCTURED PROBLEMS 303 James F. Voss 21 ARGUING BY QUESTION: A TOULMINIAN READING OF CICERO’S ACCOUNT OF THE ENTHYMEME 313 Manfred Kraus 22 THE USES OF ARGUMENT IN MATHEMATICS 327 Andrew Aberdein 23 TRANSLATING TOULMIN DIAGRAMS: THEORY NEUTRALITY IN ARGUMENT REPRESENTATION 341 Chris Reed and Glenn Rowe 24 THE TOULMIN TEST: FRAMING ARGUMENTATION WITHIN BELIEF REVISION THEORIES 359 Fabio Paglieri and Cristiano Castelfranchi 25 EIGHT THESES REFLECTING ON STEPHEN TOULMIN 379 John Woods CONTRIBUTORS 399 REFERENCES 407 INDEX 425 ACKNOWLEDGEMENTS The chapters in this volume have undergone peer review and were revised in the light of the resulting comments. We would like to thank the following referees and commentators for their help: Derek Allen, Richard T. W. Arthur, Peter Asquith, Mark Battersby, Trevor Bench-Capon, George Boger, Peter Cramer, Chris Eisenhart, James B. Freeman, Michael A. Gilbert, Tom Gordon, Leo Groarke, Dale Hample, Darrin Hicks, Anthony Hunter, Henrike Jansen, Ralph H. Johnson, James F. Klumpp, Christian Kock, Robert Kominar, Erik C. W. Krabbe, Ronald Leenes, Michael Leff, Ronald P. Loui, Peter McBurney, Daniel O’Keefe, Fabio Paglieri, Robert C. Pinto, Henry Prakken, Pedro Reygadas, Phyllis Rooney, Michael Scriven, Harvey Siegel, Guillermo Simari, Christina Slade, Robert G. Sullivan, Olaf Tans, Tim van Gelder, James Voss, Douglas Walton, Mark Weinstein, Joseph Wenzel, John Woods, John Zeleznikow. We would also like to thank the Social Sciences and Humanities Research Council of Canada for its financial support of the conference in May 2005 at McMaster University on “The uses of argument”, at which many of the papers in this volume were presented in preliminary form. The conference grant enabled us to hire an editorial assistant, Daniel Farr, to take care of the technical aspects of preparation of the manuscript of this book. Daniel was a reliable and capable editorial assistant, and we express our warm thanks to him for his dedication and professionalism. For financial support of the May 2005 conference, we thank also McMaster University’s provost and vice-president academic Ken Norrie, its vice president research Mamdouh Shoukri, its dean of humanities Nasrin Rahimieh, and the chair of its philosophy department Richard T. W. Arthur. For their support of this project and their help in preparing the manuscript, we thank Anne-Marie Blaney, Publishing Editor in Ethics and Philosophy of Law at Springer; her assistant Natalie Rieborn; Gerrit Oomen, André Tournois and Joseph Albert André of the Springer production department; and Deborah Doherty of Springer Author Support. We thank the editors of the journal Argumentation for permission to reprint eight articles from a special issue (vol. 19, no. 3, 2005) of that journal on “the Toulmin model today”. The articles are the chapters by Andrew Aberdein, James B. Freeman, David Hitchcock, Ronald P. Loui, Henry Prakken, Chris Reed and Glenn Rowe, Bart Verheij, and James F. Voss. Finally, we thank the editors of the journal Informal Logic for permission to reprint three articles from that journal. “Reasoning in Theory and Practice” by Stephen Toulmin was previously published in Informal Logic (vol. 24, no. 2, 2004), and is reprinted here with permission. “Toulmin’s Model of Argument and the Question of Relativism” by Lilian Bermejo Luque was previously published in Informal Logic (vol. 24, no. 2, 2004), and is reprinted here with permission. “Evaluating inferences: the nature and role of warrants” by Robert C. Pinto was previously published in Informal Logic, and is reprinted here with permission. VII CHAPTER 1 DAVID HITCHCOCK1 AND BART VERHEIJ2 INTRODUCTION 1Department of Philosophy, McMaster University, Hamilton, Canada L8S 4K1 2Artificial Intelligence, University of Groningen, Grote Kruisstraat 2/1, 9712 TS Groningen, The Netherlands E-mail: [email protected], [email protected] 1. THE USES OF ARGUMENT In The Uses of Argument (1958), Stephen Edelston Toulmin argued that the abstract and formal criteria of mathematical logic and of much twentieth-century epistemology had little applicability to the methods we actually use in everyday life to assess arguments. Toulmin called for a reform that would blend logic and epistemology into ‘applied logic’, focused on the structures of arguments in different fields and the corresponding differences in the standards for their appraisal. Its method was to be comparative, empirical and historical; it was to look concretely at the similarities and differences between ways of arguing and standards of proof in geometrical optics, historiography, civil litigation, morals and so forth, as these have evolved his torically. Despite the pluralism of his title, Toulmin focused on one use of argument: to defend a claim made by asserting something. He noted certain field-invariant features of our doing so. First we present a problem, expressed in a more or less clear question. We have a certain opinion in mind as our solution to this problem; Toulmin is not concerned in this book with how we did or should arrive at it. We begin by acknowledging various candidates for a solution, candidates that are ‘possible’ in the sense that they have a right to be considered. Then we consider the bearing of information at our disposal on these suggestions, perhaps concluding that some are after all ‘impossible’, perhaps identifying one as most ‘probable’ in the sense of being most deserving of acceptance, perhaps identifying one as ‘presumably’ correct unless certain unusual or exceptional conditions apply. During this process of rational justification, we throw up what Toulmin called ‘micro-arguments’ (Toulmin, 1958, p. 94), for which he proposed a field-invariant pattern of analysis designed to do justice to the process of defending a particular claim against a challenger. This pattern, which has come to be known as the ‘Toulmin model’ or ‘Toulmin scheme’, differed radically from the traditional logical analysis of a micro-argument into premisses and conclusion. First we assert 1 D. Hitchcock and B. Verheij (eds.), Arguing on the Toulmin Model: New Essays in Argument Analysis and Evaluation, 1–23. © 2006 Springer. 2 DAVID HITCHCOCK AND BART VERHEIJ something, and thus make a claim (C). Challenged to defend our claim by a questioner who asks, “What have you got to go on?”, we appeal to the relevant facts at our disposal, which Toulmin calls our data (D). It may turn out to be necessary to establish the correctness of these facts in a preliminary argument. But their acceptance by the challenger, whether immediate or indirect, does not necessarily end the defense. For the challenger may ask about the bearing of our data on our claim: “How do you get there?” Our response will at its most perspicuous take the form: “Data such as D entitle one to draw conclusions, or make claims, such as C” (p. 98). A proposition of this form Toulmin calls a warrant (W). Warrants, he notes, confer different degrees of force on the conclusions they justify, which may be signaled by qualifying our conclusion with a qualifier (Q) such as ‘necessarily’, ‘probably’ or ‘presumably’. In the latter case, we may need to mention conditions of rebuttal (R) “indicating circumstances in which the authority of the warrant would have to be set aside” (p. 101). Our task, however, is still not necessarily finished. For our challenger may question the general acceptability of our warrant: “Why do you think that?” Toulmin calls our answer to this question our backing (B). He emphasizes the great differences in kind between backings in different fields. Warrants can be defended by appeal to a system of taxonomic classification, to a statute, to statistics from a census, and so forth. It is this difference in backing that constitutes the field-dependence of our standards of argument. Ultimately, all micro- arguments depend on the combination of data and backing. In rare cases, checking the backing will involve checking the claim; Toulmin calls such arguments ‘analytic arguments.’ Most arguments are not of this sort, so that purely formal criteria do not suffice for their assessment; Toulmin calls them ‘substantial arguments’. The sort of backing that is acceptable for a given substantial argument will depend on the field to which it belongs. To illustrate the contribution of these constituents, Toulmin proposed the following diagram (p. 104): D So, Q, C Since W Unless R On account of B D for Data W for Warrant Q for Qualifier B for Backing C for Claim R for Rebuttal 1: INTRODUCTION 3 Summarizing, in The Uses of Argument Toulmin emphasized a number of points that are by now familiar, but still deserve attention: 1. Reasoning and argument involve not only support for points of view, but also attack against them. 2. Reasoning can have qualified conclusions. 3. There are other good types of argument than those of standard formal logic. 4. Unstated assumptions linking premisses to a conclusion are better thought of as inference licenses than as implicit premisses. 5. Standards of reasoning can be field-dependent, and can be themselves the subject of argumentation. Each of these points is illustrated by his layout of arguments. The rebuttal illustrates the first point, the qualifier the second point, and the warrant and backing the last three points. 2. RECEPTION OF TOULMIN’S BOOK As Toulmin himself notes in his essay in this volume, which was delivered as an address in 2005, his fellow philosophers were initially hostile to the ideas in his book. They were taken up, however, by specialists in fields like jurisprudence and psychology, who found that they fit the forms of argument and reasoning that they were studying. And Toulmin’s model was embraced by the field of speech communication in the United States, whose textbooks on argumentation now include an obligatory chapter on the Toulmin model of micro-arguments. More recently, the model has been appropriated by researchers in the fields of computer science and artificial intelligence, where it has been adapted for use in decision support systems, for instance in the domains of law and medicine. Work in these fields on topics such as defeasible reasoning, argumentation schemes and field-dependent standards of reasoning has roots in Toulmin’s ideas. Toulmin has also strongly influenced the graphical representation of argument today, e.g. in software. And some philosophers have come to take Toulmin’s ideas seriously, especially those working in what is called ‘informal logic’, the philosophical study of the analysis and evaluation of real arguments. In this sub-field, Toulmin’s book is a post-war classic. The present volume attempts to bring together the best current reflection on the Toulmin model and its current appropriation. All the essays were written in response to calls for papers for a special issue of the journal Argumentation (19: 3 [2005]) on “The Toulmin model today” and for a conference at McMaster University in May 2005 on “The uses of argument”. They are a selection from the papers submitted, revised in the light of comments by referees and conference commentators, and in subsequent discussion. The chapters are not exegetical but substantive, extending or challenging Toulmin’s ideas in ways that make fresh contributions to the theory of analyzing and evaluating arguments.