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)

The New Rhetoric is founded on the idea that since “argumentation aims at securing the adherence of those to whom it is addressed, it is, in its entirety, relative to the audience to be influenced,” says Chaïm Perelman and L. Olbrechts-Tyteca, and they rely, in particular, for their theory of argumentation on the twin concepts of universal and particular audiences: while every argument is directed to a specific individual or group, the orator decides what information and what approaches will achieve (...) the greatest adherence according to an ideal audience. This ideal, Perelman explains, can be embodied, for example, "in God, in all reasonable and competent men, in the man deliberating or in an elite.” Like particular audiences, then, the universal audience is never fixed or absolute but depends on the orator, the content and goals of the argument, and the particular audience to whom the argument is addressed. These considerations determine what information constitutes "facts" and "reasonableness" and thus help to determine the universal audience that, in turn, shapes the orator's approach. /// The adherence of an audience is also determined by the orator's use of values, a further key concept of the New Rhetoric. Perelman's treatment of value and his view of epideictic rhetoric sets his approach apart from that of the ancients and of Aristotle in particular. Aristotle's division of rhetoric into three genres–forensic, deliberative, and epideictic–is largely motivated by the judgments required for each: forensic or legal arguments require verdicts on past action, deliberative or political rhetoric seeks judgment on future action, and epideictic or ceremonial rhetoric concerns values associated with praise or blame and seeks no specific decisions. For Aristotle, the epideictic genre was of limited importance in the civic realm since it did not concern facts or policies. Perelman, in contrast, believes not only that epideictic rhetoric warrants more attention, but that the values normally limited to that genre are in fact central to all argumentation. "Epideictic oratory," Perelman argues, "has significant and important argumentation for strengthening the disposition toward action by increasing adherence to the values it lauds.” These values are central to the persuasiveness of arguments in all rhetorical genres since the orator always attempts to "establish a sense of communion centered around particular values recognized by the audience.”. (shrink)

Provides comprehensive coverage of logical structure as well as the techniques of formal reasoning.

In many actual arguments, the conclusion seems intuitively to follow from the premisses, even though we cannot show that it follows logically. The traditional approach to evaluating such arguments is to suppose that they have an unstated premiss whose explicit addition will produce an argument where the conclusion does follow logically. But there are good reasons for doubting that people so frequently leave the premisses of their arguments unstated. The inclination to suppose that they do stems from the belief that (...) the only way in which an argument's conclusion can follow definitely from its premisses is to follow logically. I argue that this belief is mistaken. I propose a revision of the current generic conception of logical consequence, and its variant specifications, to avoid the paradoxes of strict implication. The revised conception can then be naturally extended to include also what we might call 'enthymematic consequence'. This concept is a kind of consequence, whose properties merit investigation. (shrink)