This critical note responds to Guiaşu and Tindale’s “Logical fallacies and invasion biology,” from our perspective as ecologists and philosophers of science engaged in debates about invasion biology and invasive species. We agree that “the level of charges and dismissals” surrounding these debates might be “unhealthy” and that “it will be very difficult for dialogues to move forward unless genuine attempts are made to understand the positions being held and to clarify the terms involved.” Although they raise several important (...) scientific, conceptual, and ethical issues at the foundations of invasion biology, we believe Guiaşu and Tindale’s attempts to clarify the debate were unsuccessful. Like some other critics of the field, they tend to misrepresent invasion biology by cherry-picking and constructing “straw people,” inaccurately portraying invasion biology, and thus failing to elevate the dialogue. In this critique, we clarify areas in the invasion biology literature misrepresented by Guiaşu and Tindale. We attempt to provide a more balanced view of areas of reasonable debate within invasion biology, including disputes about empirical evidence, diverse risk attitudes, and other diverse ethical commitments. (shrink)

In this article, we address fallacious analogical reasoning and the Metaphoric Fallacy to a Deductive Inference (MFDI), recently discussed by B. Lightbody and M. Berman (2010). We claim that the authors’ proposal to introduce a new fallacy is only partly justified. We also argue that, in some relevant cases, fallacious analogical reasoning involving metaphors is only affected by the use of quaternio terminorum.

This paper argues that some traditional fallacies should be considered as reasonable arguments when used as part of a properly conducted dialog. It is shown that argumentation schemes, formal dialog models, and profiles of dialog are useful tools for studying properties of defeasible reasoning and fallacies. It is explained how defeasible reasoning of the most common sort can deteriorate into fallacious argumentation in some instances. Conditions are formulated that can be used as normative tools to judge (...) whether a given defeasible argument is fallacious or not. It is shown that three leading violations of proper dialog standards for defeasible reasoning necessary to see how fallacies work are: (a) improper failure to retract a commitment, (b) failure of openness to defeat, and (c) illicit reversal of burden of proof. (shrink)

The public must make assessments of a range of health-related issues. However, these assessments require scientific know-ledge which is often lacking or ineffectively utilized by the public. Lay people must use whatever cognitive resources are at their disposal to come to judgement on these issues. It will be contended that a group of arguments—so-called informal fallacies—are a valuable cognitive resource in this regard. These arguments serve as cognitive heuristics which facilitate reasoning when knowledge is limited or beyond the (...) grasp of reasoners. The results of an investigation into the use of these arguments by the public are reported. (shrink)

Reason and Doctrinepresents a simple, straightforward outline of Christian dogmas that not only contradict the scientific world view, they have no foundation in scripture. The author considers a wide range of ancient texts in Greek, Hebrew, and Latin, and their contemporary translations, and discusses the texts that have come to be known as Paul's letters, where he finds distinct errors from the references to Genesis to the accepted story of Jesus as a blood sacrifice. While fully documented and founded on (...) a scholarly investigation, the book is written for general readers. (shrink)

lt is now commonplace in fallacy inquiry for many of the traditional informal fallacies to be viewed as reasonable or nonfallacious modes of argument. Central to this evaluative shift has been the attempt to examine traditional fallacies within their wider contexts of use. However, this pragmatic turn in fallacy evaluation is still in its infancy. The true potential of a contextual approach in the evaluation of the fallacies is yet to be explored. I examine how, in the (...) context of scientific inquiry, certain traditional fallacies function by conferring epistemic gains upon inquiry. Specifically, I argue that these fallacies facilitate the progression of inquiry, particularly in the initial stages ofinquiry when the epistemic context is one of uncertainty. The conception of these fallacies that emerges is that of heuristics of reasoning in contexts of epistemic uncertainty. (shrink)

A concise, easy-to-read introduction to informal logic, "With Good Reason" offers both comprehensive coverage of informal fallacies and an abundance of engaging examples of both well-conceived and faulty arguments. A long-time favorite of both students and instructors, the text continues in its sixth edition to provide an abundance of exercises that help students identify, correct, and avoid common errors in argumentation.

This text is designed to help students construct and evaluate arguments.

An infonnal fallacy is a reasoning error with three features: the reasoning employs an implicit cogent pattern; the fallacy results from one or more false premises; there is culpable ignorance or deception associated with the falsity of the premises. A reconstruction and analysis of the cogent reasoning patterns in fourteen standard infonnal fallacy types plus several variations are given. Defense of the CMR account covers: a general failure to apply the principle of charity in informal fallacy contexts; (...) empirical evidence for it; how it explains Walton's point that there are both fallacious and non-fallacious instances of fallacy types; how it avoids most "relevance" problems, pennits clearer taxonomizing, and promises pedagogical advantages; how it solves a "demarcation problem.". (shrink)

The author recommends an involved study of logical fallacies in order to provide a database of testable hypotheses for error reasoning. The purpose of the study is to make the study of logical fallacies accessible to a wider audience. Following a recent study conducted by Ludwig Schlecht, the author presents a diagnostic method to illustrate how an argument can be fallacious from the breach of particular rational principles. The diagnosis method also serves as investigation into other forms (...) of argumentative fallacies and the author suggests it could later be the basis for training programs for undergraduate students in logic courses. (shrink)

Attempts to evaluate a belief or argument on the basis of its cause or origin are usually condemned as committing the genetic fallacy. However, I sketch a number of cases in which causal or historical factors are logically relevant to evaluating a belief, including an interesting abductive form that reasons from the best explanation for the existence of a belief to its likely truth. Such arguments are also susceptible to refutation by genetic reasoning that may come very close to (...) the standard examples given of supposedly fallacious genetic reasoning. (shrink)

The author designed the Reasoning Analysis Test to provide empirical support for the CRM analysis of informal fallacies. While informal, the results provide presumptive evidence that those committing informal fallacies may tacitly reason as predicted by CRM. Davis has argued persuasively that Gricean theory has not lived up to expectations, In light of his critique, the CRM analyses of Begging the Question and Equivocation are amended. Johnson has provided standards for judging any theory of informal fallacies. (...) It is argued that CRM survives the Standard Critique and sufficiently meets Johnson's other criteria. (shrink)

Aristotle studies syllogistic argumentation in Sophistical Refutations and Prior Analytics. In the latter he focuses on the formal and syntactic character of arguments and treats the sullogismoi and non-sullogismoi as argument patterns with valid or invalid instances. In the former Aristotle focuses on semantics and rhetoric to study apparent sullogismoi as object language arguments. Interpreters usually take Sophistical Refutations as considerably less mature than Prior Analytics. Our interpretation holds that the two works are more of a piece than previously believed (...) and, indeed, that Aristotle's treatment of fallacious reasoning presupposes the results of the formal theory. (shrink)

Fallacies and Argument Appraisal presents an introduction to the nature, identification, and causes of fallacious reasoning, along with key questions for evaluation. Drawing from the latest work on fallacies as well as some of the standard ideas that have remained relevant since Aristotle, Christopher Tindale investigates central cases of major fallacies in order to understand what has gone wrong and how this has occurred. Dispensing with the approach that simply assigns labels and brief descriptions of (...) class='Hi'>fallacies, Tindale provides fuller treatments that recognize the dialectical and rhetorical contexts in which fallacies arise. This volume analyzes major fallacies through accessible, everyday examples. Critical questions are developed for each fallacy to help the student identify them and provide considered evaluations. (shrink)

For Aristotle the fallacy of accident arises from mistakes about being per accidens and not from accidental predication. Mistakes in perceiving per accidens come from our judgements about being per accidens and so commit that fallacy. Practical syllogisms have the same formal structure as being and perceiving per accidens . Moreover perceiving per accidens typically provides the minor premise for the practical syllogism as it makes it possible for us to know singular propositions, especially those about substances. Thus these minor (...) premises may come about through fallacious reasoning, what today would be called reasoning via collateral information. On account of these foundations for the practical syllogism, even a person of practical wisdom will need a lot of luck to avoid mistakes. (shrink)

This style of argument comes up everywhere in the philosophy of practical reason, leveled against theories of the norm of means-end coherence on intention, against Humean theories of reasons, and many other places. It comes up in normative moral theory – for example, in arguments against buck-passing. It comes up in epistemology, in discussions of how to account for the rational connection between believing the premises of a valid argument and believing its conclusion. And it comes up in political philosophy, (...) where one of its most salient occurrences is in the so-called ‘leveling down’ objection to egalitarianism. (shrink)

Abstract David Sobel (2001) objects to Bernard Williams's internalism, the view that an agent has a reason to perform an action only if she has some motive that will be served by performing that action. Sobel is an unusual challenger in that he endorses neo-Humean subjectivism, ?the view that it is the agent's subjective motivational set that makes it the case that an agent does or does not have a reason to φ? (219). Sobel's objection in fact arises from this (...) very commitment. Internalism, he says, is incompatible with the best subjectivist accounts of reasons for action?accounts that suggest that there are what he calls fragile reasons and perhaps also superfragile ones, both of which allegedly provide for counterexamples to internalism. I argue that such reasons do not in fact threaten internalism. I then briefly explore whether internalism is vulnerable to a related charge?that it commits the conditional fallacy. (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)

We are happy to present to the reader the first book of our Applied Logic Series. Walton's book on the fallacies of ambiguity is firmly at the heart of practical reasoning, an important part of applied logic. There is an increasing interest in artifIcial intelligence, philosophy, psychol ogy, software engineering and linguistics, in the analysis and possible mechanisation of human practical reasoning. Continuing the ancient quest that began with Aristotle, computer scientists, logicians, philosophers and linguists are vigorously (...) seeking to deepen our understanding of human reasoning and argumentation. Significant communities of researchers are actively engaged in developing new approaches to logic and argumentation, which are better suited to the urgent needs of today's applications. The author of this book has, over many years, made significant contributions to the detailed analysis of practical reasoning case studies, thus providing solid foundations for new and more applicable formal logical systems. We welcome Doug Walton's new book to our series. (shrink)

The fallacy fallacy is either the misdiagnosis of fallacy or the supposition that the conclusion of a fallacy must be a falsehood. This paper explores the relevance of these and related errors of reasoning for the appraisal of arguments, especially within virtue theories of argumentation. In particular, the fallacy fallacy exemplifies the Owl of Minerva problem, whereby tools devised to understand a norm make possible new ways of violating the norm. Fallacies are such tools and so are vices. (...) Hence a similar problem arises with argumentative vices. Fortunately, both instances of the problem have a common remedy. (shrink)

This paper has two central purposes: the first is to survey some of the more important examples of fallacious argument, and the second is to examine the frequent use of these fallacies in support of the psychological construct: Attention Deficit Hyperactivity Disorder. The paper divides 12 familiar fallacies into three different categories—material, psychological and logical—and contends that advocates of ADHD often seem to employ these fallacies to support their position. It is suggested that all researchers, whether into (...) ADHD or otherwise, need to pay much closer attention to the construction of their arguments if they are not to make truth claims unsupported by satisfactory evidence, form or logic. (shrink)

Although fallacies have been common since Aristotle, until recently little attention has been devoted to identifying and defining them. Furthermore, the concept of fallacy itself has lacked a sufficiently clear meaning to make it a useful tool for evaluating arguments. Douglas Walton takes a new analytical look at the concept of fallacy and presents an up-to-date analysis of its usefulness for argumentation studies. Walton uses case studies illustrating familiar arguments and tricky deceptions in everyday conversation where the charge of (...) fallaciousness is at issue. The numerous case studies show in concrete terms many practical aspects of how to use textual evidence to identify and analyze fallacies and to evaluate arguments as fallacious. Walton looks at how an argument is used in the context of conversation. He defines a fallacy as a conversational move, or sequence of moves, that is supposed to be an argument that contributes to the purpose of the conversation but in reality interferes with it. The view is a pragmatic one, based on the assumption that when people argue, they do so in a context of dialogue, a conventionalized normative framework that is goal-directed. Such a contextual framework is shown to be crucial in determining whether an argument has been used correctly. Walton also shows how examples of fallacies given in the logic textbooks characteristically turn out to be variants of reasonable, even if defeasible or questionable arguments, based on presumptive reasoning. This is the essence of the evaluation problem. A key thesis of the book, which must not be taken for granted as previous textbooks have so often done, is that you can spot a fallacy from how it was used in a context of dialogue. This is an innovative and even, as Walton notes, "a radical and controversial" theory of fallacy. (shrink)

Fallacies are things people commit, and when they commit them they do something wrong. What kind of activities are people engaged in when they commit fallacies, and in what way are they doing something wrong? Many different things are called fallacies. The diversity of the use of the concept of a fallacy suggests that we are dealing with a family of cases not related by a common essence. However, we suggest a simple account of the nature of (...) fallacies which encompasses them all, viz., the term “fallacy” is our most general term for criticizing any general procedure used for the fixation of beliefs that has an unacceptably high tendency to generate false or unfounded beliefs, relative to that method of fixing beliefs. Very different sorts of things called fallacies are examined in the light of this account, e.g., denying the antecedent, circular arguments, so-called informal fallacies, and propositions said to be fallacies. We do not provide a theory of fallacies. Still, on our account pretty much all of those things that have been called fallacies are fallacies, and they have been called fallacies for pretty much the same reasons. (shrink)

During the last decades, the psychology of reasoning has identified experimentally many fallacies committed by spontaneous reasoners. Given these experimental results, some theories have been developed about this phenomenon, mainly algorithmic theories. This paper develops instead a computational modelling of these current fallacies which appear as simplifications in the treatment of information that do not respect the formal rules of classical propositional logic. These fallacies are explained as crushes in the Klein group structure and so, in (...) squares of opposition. These crushes are an effect of not to take into account the dual of the binary operator at work in the major premise of the inference. This analysis allows predictions on fallacies not identified before, which are fallacies produced when reasoning with incompatibilities. The paper concludes with consequences of the analysis on pedagogical strategies for the teaching of logic. (shrink)

In the debate surrounding the morality and legality of the practices of physician-assisted death and euthanasia, a common logical argument regularly employed against these practices is the “slippery slope argument.” One formulation of this argument claims that acceptance of physician-assisted death will eventually lead down a “slippery slope” into acceptance of active euthanasia, including its voluntary, non-voluntary, and/or involuntary forms, through psychological and social processes that warp a society’s values and moral perspective of a practice over an extended period of (...) time. This formulation is known as the psychological slippery slope argument. This paper analyzes the psychological slippery slope argument as it is applied to the practice of physician-assisted death, and utilizing recent empirical evidence from various nations around the world that practice physician-assisted death and/or euthanasia, the paper argues that employing the psychological slippery slope argument against physician-assisted death is logically fallacious, this kind of slippery slope is unfounded in practice, and thus the psychological slippery slope argument is insufficient on its own to justify continued legal prohibition of physician-assisted death. (shrink)

Mr. Rush Limbaugh may be our most influential media personality, but he is not the most clear-thinking. Logic and Mr. Limbaugh not only exposes the fallacies in Mr. Limbaugh's persuasive arguments - it also gives a hilarious introduction to Logic, the science of correct reasoning.

Fallacies A fallacy is a kind of error in reasoning. The list of fallacies below contains 230 names of the most common fallacies, and it provides brief explanations and examples of each of them. Fallacious arguments should not be persuasive, but they too often are. Fallacies may be created unintentionally, or they may be created … Continue reading fallacies →.

Robert Kimball, in “What’s Wrong with Argumentum Ad Baculum?” (Argumentation, 2006) argues that dialogue-based models of rational argumentation do not satisfactorily account for what is objectionable about more malicious uses of threats encountered in some ad baculum arguments. We review the dialogue-based approach to argumentum ad baculum, and show how it can offer more than Kimball thinks for analyzing such threat arguments and ad baculum fallacies.

The paper argues that the two best known formal logical fallacies, namely denying the antecedent (DA) and affirming the consequent (AC) are not just basic and simple errors, which prove human irrationality, but rather informational shortcuts, which may provide a quick and dirty way of extracting useful information from the environment. DA and AC are shown to be degraded versions of Bayes’ theorem, once this is stripped of some of its probabilities. The less the probabilities count, the closer these (...) fallacies become to a reasoning that is not only informationally useful but also logically valid. (shrink)

Bayesian reasoning has been applied formally to statistical inference, machine learning and analysing scientific method. Here I apply it informally to more common forms of inference, namely natural language arguments. I analyse a variety of traditional fallacies, deductive, inductive and causal, and find more merit in them than is generally acknowledged. Bayesian principles provide a framework for understanding ordinary arguments which is well worth developing.

Conceptual metaphors facilitate both productive and pernicious analogical reasoning. This article addresses the question: When and why does the frequently helpful use of metaphor become pernicious? By applying the most influential theoretical framework from cognitive psychology in analysing the philosophically most prominent example of pernicious metaphorical reasoning, we identify a philosophically relevant but previously undescribed fallacy in analogical reasoning with metaphors. We then outline an explanation of why even competent thinkers commit this fallacy and obtain a psychologically (...) informed ‘debunking’ explanation of the kind experimental philosophy’s ‘sources project’ seeks. (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)

Beliefs like the Gambler's Fallacy and the Hot Hand have interested cognitive scientists, economists, and philosophers for centuries. We propose that these judgment patterns arise from the observer's mental models of the sequence-generating mechanism, moderated by the strength of belief in an a priori base rate. In six behavioral experiments, participants observed one of three mechanisms generating sequences of eight binary events: a random mechanical device, an intentional goal-directed actor, and a financial market. We systematically manipulated participants’ beliefs about the (...) base rate probabilities at which different outcomes were generated by each mechanism. Participants judged 18 sequences of outcomes produced by a mechanism with either an unknown base rate, a specified distribution of three equiprobable base rates, or a precise, fixed base rate. Six target sequences ended in streaks of between two and seven identical outcomes. The most common predictions for subsequent events were best described as pragmatic belief updating, expressed as an increasingly strong expectation that a streak of identical signals would repeat as the length of that streak increased. The exception to this pattern was for sequences generated by a random mechanical device with a fixed base rate of.50. Under this specific condition, participants exhibited a bias toward reversal of streaks, and this bias was larger when participants were asked to make a dichotomous choice versus a numerical probability rating. We review alternate accounts for the anomalous judgments of sequences and conclude with our favored interpretation that is based on Rabin's version of Tversky & Kahneman's Law of Small Numbers. (shrink)