In the pragma-dialectical approach, fallacies are considered incorrect moves in a discussion for which the goal is successful resolution of a dispute. Ten rules are given for effective conduct at the various stages of such a critical discussion. Fallacies are discussed as violations of these rules, taking into account all speech acts which are traditionally recognized as fallacies. Special attention is paid to the role played by implicitness in fallacies in everyday language use. It is stressed that identifying and acknowledging (...) fallacies in ordinary discussions always has a conditional character. Differences between the pragma-dialectical perspective, the Standard Treatment, and the formal logic approach to fallacy analysis are discussed. (shrink)

The paper describes four dialogue systems, developed in the tradition of Charles Hamblin. The first system provides an answer for Achilles in Lewis Carroll's parable, the second an analysis of the fallacy of begging the question, the third a non-psychologistic account of conversational implicature, and the fourth an analysis of equivocation and of objections to it. Each avoids combinatorial explosions, and is intended for real-time operation.

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 'Evolution of Cooperation' addresses a simple yet age-old question; If living things evolve through competition, how can cooperation ever emerge? Despite the abundant evidence of cooperation all around us, there existed no purely naturalistic answer to this question until 1979, when Robert Axelrod famously ran a computer tournament featuring a standard game-theory exercise called The Prisoner's Dilemma. To everyone's surprise, the program that won the tournament, named Tit for Tat, was not only the simplest but the most "cooperative" entrant. (...) This unexpected victory proved that cooperation - one might even say altruism - is mathematically possible and therefore needs no hidden hand or divine agent to create and sustain it. A great roadblock to the understanding of all sorts of behavior was at last removed. The updated edition includes an extensive new chapter on cooperation in cancer cells and among terrorist organizations. (shrink)

INTRODUCTION When Karl Popper published in' his definition of closer-to-the- truth this was an important intellectual event, but not a shocking one. ...