In this paper, I argue that arguments from expert opinion, i.e., inferences from “Expert E says that p” to “p,” where the truth value of p is unknown, are weak arguments. A weak argument is an argument in which the premises, even if true, provide weak support—or no support at all—for the conclusion. Such arguments from expert opinion are weak arguments unless the fact that an expert says that p makes p significantly more likely to be true. However, research on (...) expertise shows that expert opinions are only slightly more accurate than chance and much less accurate than decision procedures. If this is correct, then it follows that arguments from expert opinion are weak arguments. (shrink)

The aim of the paper is to advance the theory of argument or inference schemes by suggesting answers to questions raised by Walton's Argumentation Schemes for Presumptive Reasoning (1996), specifically on: the relation between argument and reasoning; distinguishing deductive from presumptive schemes, the origin of schemes and the probative force of their use; and the motivation and justification for their associated critical questions.

The subject of this paper, Excuses, is one not to be treated, but only to be introduced, within such limits. It is, or might be, the name of a whole branch, even a ramiculated branch, of philosophy, or at least of one fashion of philosophy. I shall try, therefore, first to state what the subject is, why it is worth studying, and how it may be studied, all this at a regrettably lofty level: and then I shall illustrate, in more (...) congenial but desultory detail, some of the methods to be used, together with their limitations, and some of the unexpected results to be expected and lessons to be learned. Much, of course, of the amusement, and of the instruction, comes in drawing the coverts of the microglot, in hounding down the minutiae, and to this I can do no more here than incite you. But I owe it to the subject to say, that it has long afforded me what philosophy is so often thought, and made, barren of -- the fun of discovery, the pleasures of co-operation, and the satisfaction of reaching agreement. (shrink)

For more than six decades, and for thousands of students, Introduction to Logic has been the gold standard in introductory logic texts. In this 15th Edition, Carl Cohen and Victor Rodych update Irving M. Copi's classic text, improving on its many strengths and introducing new and helpful material that will greatly assist both students and instructors.

Accounts of arguments from expert opinion take it for granted that expert judgments count as (defeasible) evidence for propositions, and so an argument that proceeds from premises about what an expert judges to a conclusion that the expert is probably right is a strong argument. In Mizrahi (2013), I consider a potential justification for this assumption, namely, that expert judgments are significantly more likely to be true than novice judgments, and find it wanting because of empirical evidence suggesting that expert (...) judgments under uncertainty are not significantly more likely to be true than novice judgments or even chance. In this paper, I consider another potential justification for this assumption, namely, that expert judgments are not influenced by the cognitive biases novice judgments are influenced by, and find it wanting, too, because of empirical evidence suggesting that experts are vulnerable to pretty much the same cognitive biases that novices are vulnerable to. If this is correct, then the basic assumption at the core of accounts of arguments from expert opinion, namely, that expert judgments count as (defeasible) evidence for propositions, remains unjustified. (shrink)

Featuring an exceptionally clear writing style and a wealth of real-world examples and exercises, Logic, Second Edition, shows how logic relates to everyday life, demonstrating its applications in such areas as the workplace, media and entertainment, politics, science and technology, student life, and elsewhere.Thoroughly revised and expanded in this second edition, the text now features 2600 exercises, more than 1000 of them new; three new chapters on legal arguments, moral arguments, and analyzing a long essay; enhanced pedagogy; and much more.FEATURES* (...) 2600 exercises--more than 1000 of them new--breathe new life into logic* Real-world examples help bring logic down to earth for students* A unique, extended explanation or model of the answer to the first question of each "Check Your Understanding" section shows students what is expected of their answers* An additional 25% of the exercises are answered at the back of the book* "Profiles in Logic" provide short sketches of logicians, philosophers, mathematicians, and others associated with logic* "Logic Challenge" problems present puzzles and paradoxes that end each chapter on a fun note* Additional pedagogical elements--marginal definitions, key terms, a glossary, reference boxes, and bulleted chapter summaries--make the material even more accessible* Detailed guides help students learn to create "truth tables" and Venn diagramsSUPPORT PACKAGEAn Instructor's Manual with Computerized Test Bank on CD includes: Solutions to all exercises in the book, enhanced by explanations and answers that elucidate the details of the correct answersKey Terms and a summary for each chapterA customizable Computerized Test Bank--with multiple-choice, true/false, and fill-in-the-blank questions--that allows instructors to give exams or homework problems that can be auto-gradedA traditional "pencil-and-paper" Test Bank and answer key containing the same questions as the Computerized Test BankPowerPoint-based lecture outlinesThe Instructor's Manual with Computerized Test Bank and the traditional Test Bank are also available in printed format.A Companion Website offers:Instructor Resources :A downloadable version of the Instructor's Manual PowerPoint-based lecture outlinesStudent Resources:Brief chapter summariesInteractive Flash Cards with key terms and definitionsWeb links and other media resourcesPractice quizzes with answers and explanations The Learning Management System Cartridges include, in a fully downloadable format:Instructor's Manual and Computerized Test Bank Student material from the companion websiteThe Perfect Text for Your Course... No Matter How You Teach ItYour course is unique; you have your own teaching philosophy and style. Whether you teach traditional Introduction to Logic, Critical Thinking/Informal Logic, or Formal Logic, Baronett: Logic, Second Edition, can be tailored to fulfill your course needs.We'll make it easy for you; choose one of our Alternate Editions or build the book you want, chapter by chapter.Option 1. Author Stan Baronett has suggested four Alternate Editions that may work for you. Each Alternate Edition comes in full color, with answers to problems, a full glossary, and an index. The books are in stock and available for ordering. Please see the ISBN information below.Logic: Concise EditionChapters 1, 3, 4, 5, 6, 7, 8Order using ISBN: 978-0-19-994129-2Logic: An Emphasis on Critical Thinking and Informal LogicChapters 1, 2, 3, 4, 10, 11, 12, 13 A-E, 14, 15Order using ISBN: 978-0-19-994128-5Logic: An Emphasis on Formal LogicChapters 1, 5, 6, 7, 8, 9Order using ISBN: 978-0-19-994126-1Logic: With Diagramming used in Chapter 4. Informal FallaciesFull textOrder using ISBN: 978-0-19-997081-0Option 2. Create your own customized textbook by choosing the specific chapters that you need for your course. Please contact your Oxford University Press Sales Representative or call 800.280.0280 for details. (shrink)

In this contribution, I will develop a comprehensive tool for the reconstruction and evaluation of argumentation from expert opinion. This is done by analyzing and then combining two dialectical accounts of this type of argumentation. Walton’s account of the ‘appeal to expert opinion’ provides a number of useful, but fairly unsystematic suggestions for critical questions pertaining to argumentation from expert opinion. The pragma-dialectical account of ‘argumentation from authority’ offers a clear and systematic, but fairly general framework for the reconstruction and (...) evaluation of this type of argumentation. The tool is developed by incorporating Walton’s critical questions into a pragma-dialectical framework. (shrink)

This paper provides a typology of appeals to authority, identifying three distinct types: that which is based on a command; that which is based on expertise; and that which is based on dignity. Each type is distinguished with respect to the reaction that a failure to follow it ordinarily evokes. The rhetorical roots of Locke's ad verecundiam are traced to the rhetorical practices of ancient Rome.

Antoine Arnauld and Pierre Nicole were philosophers and theologians associated with Port-Royal Abbey, a centre of the Catholic Jansenist movement in seventeenth-century France. Their enormously influential Logic or the Art of Thinking, which went through five editions in their lifetimes, treats topics in logic, language, theory of knowledge and metaphysics, and also articulates the response of 'heretical' Jansenist Catholicism to orthodox Catholic and Protestant views on grace, free will and the sacraments. In attempting to combine the categorical theory of the (...) proposition with a Cartesian account of knowledge, their Logic represents the classical view of judgment which inspired the modern transformation in logic and semantic theory by Frege, Russell, Wittgenstein and recent philosophers. This edition presents a new translation of the text, together with a historical introduction and suggestions for further reading. (shrink)

According to the argument scheme approach, to evaluate a given scheme-saturating instance completely does entail asking all critical questions relevant to it. Although this is a central task for argumentation theorists, the field currently lacks a method for providing a complete argument evaluation. Approaching this task at the meta-level, we combine a logical with a substantive approach to the argument schemes by starting from Toulmin’s schema: ‘data, warrant, so claim’. For the yet more general schema: ‘premise; if premise, then conclusion; (...) so conclusion’, we forward a meta-level CQ-list that is arguably both complete and applicable. This list should inform ongoing theoretical efforts at generating appropriate object-level CQs for specific argument schemes. (shrink)

The thesis of the paper holds that some future developments of argumentation theory may be inspired by the rich logico-methodological legacy of the Lvov–Warsaw School (LWS), the Polish research movement that was most active from 1895 to 1939. As a selection of ideas of the LWS which exploit both formal and pragmatic aspects of the force of argument, we present: Ajdukiewicz’s account of reasoning and inference, Bocheński’s analyses of superstitions or dogmas, and Frydman’s constructive approach to legal interpretation. This paper (...) does not aim at exhaustive elaboration of any of these topics or their usefulness in current discussions within argumentation theory. Rather, we intend to indicate chosen directions of a potentially fruitful research program for the emerging Polish School of Argumentation which would consist in application of methods and conceptions elaborated by the LWS to selected open problems of contemporary research on argumentation. (shrink)

Argumentation theorists often disagree about which scheme best represents a given type of argument. Unfortunately, authors sometimes become involved in fruitless pseudo-agreement because they fail to perceive that their supposedly competing schemes are means for achieving different practical or theoretical goals. This paper explains some of the different purposes that an argument scheme may serve, and it indicates how the relevant type of pseudo-disagreement may be avoided.

This article evaluates the strengths and weaknesses of arguments based on appeals to expertise. The intersection of two areas is explored: (i) the traditional argumentum ad verecundiam (literally, “appeal to modesty,” but characteristically the appeal to the authority of expert judgment) in informal logic, and (ii) the uses of expert systems in artificial intelligence. The article identifies a model of practical reasoning that underlies the logic of expert systems and the model of argument appropriate for the informal logic of the (...) argumentum ad verecundiam. (shrink)

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

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