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.

This article described three heuristics that are employed in making judgements under uncertainty: representativeness, which is usually employed when people are asked to judge the probability that an object or event A belongs to class or process B; availability of instances or scenarios, which is often employed when people are asked to assess the frequency of a class or the plausibility of a particular development; and adjustment from an anchor, which is usually employed in numerical prediction when a relevant value (...) is available. These heuristics are highly economical and usually effective, but they lead to systematic and predictable errors. A better understanding of these heuristics and of the biases to which they lead could improve judgements and decisions in situations of uncertainty. (shrink)

Unlike most texts in critical thinking, _Reason in the Balance_ focuses broadly on the practice of critical inquiry, the process of carefully examining an issue in order to come to a reasoned judgment. Although analysis and critique of individual arguments have an important role to play, this text goes beyond that dimension to emphasize the various aspects that go into the practice of inquiry, including identifying issues and relevant contexts, understanding competing cases, and making a comparative judgment._ Distinctive Features of (...) the Text:_ Emphasis on applying critical thinking to complex issues with competing arguments Inclusion of chapters on inquiry in specific contexts Attention to the dialogical aspects of inquiry, including sample dialogues Emphasis on the spirit of inquiry _The Second Edition Features:_ Updated examples and items of current interest New dialogues on vaccination, prostitution, and climate change New material on biases in reasoning, including emotional, psychological, social, and cognitive _The _Reason in the Balance_ Website includes:_ An Appendix on Logic Exercises Quizzes. (shrink)

Hamblin held that the conception of 'fallacy' as an argument that seems valid but is not really so was the dominant conception of fallacy in the history of fallacy studies. The present paper explores the extent of support that there is for this view. After presenting a brief analysis of 'the standard definition of fallacy,' a number of the definitions of 'fallacy' in texts from the middle of this century – from the standard treatment – are considered. This is followed (...) by a review of the definitions of 'fallacy' in the earlier history of logic books, including those of Aristotle, Whately, Mill and De Morgan. The essay concludes that there is scarcely any support for Hamblin's view that this particular definition of 'fallacy' was widely held. (shrink)

Five errors that fit under the category of jumping to a conclusion are identified: (1) arguing from premises that are insufficient as evidence to prove a conclusion (2) fallacious argument from ignorance, (3) arguing to a wrong conclusion, (4) using defeasible reasoning without being open to exceptions, and (5) overlooking/suppressing evidence. It is shown that jumping to a conclusion is best seen not as a fallacy itself, but as a more general category of faulty argumentation pattern underlying these errors and (...) some related fallacies. (shrink)

This paper offers a solution to the problem of understanding how a fallacious argument can be deceptive by “seeming to be valid”, or (better) appearing to be a better argument of its kind than it really is. The explanation of how fallacies are deceptive is based on heuristics and paraschemes. Heuristics are fast and frugal shortcuts to a solution to a problem that sometimes jump to a conclusion that is not justified. In fallacious instances, according to the theory proposed, this (...) jump overlooks prerequisites of the defeasible argumentation scheme for the type of argument in question. Three informal fallacies, argumentum ad verecundiam , argumentum ad ignorantiam and fear appeal argument, are used to illustrate and explain the theory. (shrink)

The paper examines Walton‘s concept of fallacy as it develops throughthree stages of his work: from the early series of papers co-authored withJohn Woods; through a second phase of involvement with thepragma-dialectical perspective; and on to the final phase in which heoffers a distinct pragmatic theory that reaches beyond the perceived limitsof the pragma-dialectical account while still exhibiting a debt to thatperspective and the early investigations with Woods. It is observed how Walton‘s model of fallacy is established in distinction to (...) its competitors,and its various problems and successes are discussed. (shrink)

This paper looks around among the major traditional fallacies — centering mainly around the so-called “gang of eighteen” — to discuss which of them should properly be classified as fallacies of relevance. The paper argues that four of these fallacies are fallacies primarily because they are failures of relevance in argumentation, while others are fallacies in a way that is more peripherally related to failures of relevance. Still others have an even more tangential relation to failures of relevance. This paper (...) is part of a larger research project on dialecical relevance in argumentative discourse, currently underway in collaboration with Frans van Eemeren and Rob Grootendorst. (shrink)

We argue that the central goal of critical thinking is the making of reasoned judgments. Arriving at reasoned judgments in most cases is a dialectical process involving the comparative weighing of a variety of contending positions and arguments. Recognizing this dialectical dimension means that critical thinking pedagogy should focus on the kind of comparative evaluation which we make in actual contexts of disagreement and debate.

This paper attempts to systematically characterize critical reactions in argumentative discourse, such as objections, critical questions, rebuttals, refutations, counterarguments, and fallacy charges, in order to contribute to the dialogical approach to argumentation. We shall make use of four parameters to characterize distinct types of critical reaction. First, a critical reaction has a focus, for example on the standpoint, or on another part of an argument. Second, critical reactions appeal to some kind of norm, argumentative or other. Third, they each have (...) a particular illocutionary force, which may include that of giving strategic advice to the other. Fourth, a critical reaction occurs at a particular level of dialogue (the ground level or some meta-level). The concepts here developed shall be applied to discussions of critical reactions by Aristotle and by some contemporary authors. (shrink)