Typically, common knowledge is taken as grounds for the acceptability of a claim, while appeals to popularity are seen as fallacious attempts to support a claim. This paper poses the question of whether there is any categorical difference between appeals to common knowledge and appeals to popular opinion as argumentative moves. In answering this question, I argue that appeals to common knowledge do not, on their own, provide adequate grounds for a claim’s acceptability.

Knowledge is a highly valued state in which a person is in cognitive contact with reality. It is, therefore, a relation. On one side of the relation is a conscious subject, and on the other side is a portion of reality to which the knower is directly or indirectly related. While directness is a matter of degree, it is convenient to think of knowledge of things as a direct form of knowledge in comparison to which knowledge about things is indirect. (...) The former has often been called knowledge by acquaintance since the subject is in experiential contact with the portion of reality known, whereas the latter is propositional knowledge since what the subject knows is a true proposition about the world. Knowing Roger is an example of knowledge by acquaintance, while knowing that Roger is a philosopher is an example of propositional knowledge. Knowledge by acquaintance includes not only knowledge of persons and things, but also knowledge of my own mental states. In fact, the knower's own mental states are often thought to be the most directly knowable portion of reality. (shrink)

Change in View offers an entirely original approach to the philosophical study of reasoning by identifying principles of reasoning with principles for revising one's beliefs and intentions and not with principles of logic. This crucial observation leads to a number of important and interesting consequences that impinge on psychology and artificial intelligence as well as on various branches of philosophy, from epistemology to ethics and action theory. Gilbert Harman is Professor of Philosophy at Princeton University. A Bradford Book.

Arguments from popular opinion have long been regarded with suspicion, and in most logic textbooks the _ad populum _argument is classified as a fallacy. Douglas Walton now asks whether this negative evaluation is always justified, particularly in a democratic system where decisions are based on majority opinion. In this insightful book, Walton maintains that there is a genuine type of argumentation based on commonly accepted opinions and presumptions that should represent a standard of rational decision-making on important issues, especially those (...) of a personal and political nature. He shows how to judge arguments based on appeals to popular opinion in a more balanced way, identifying eleven subtypes of the _ad populum_ argument and providing a pragmatic method to evaluate each of these types. Walton has examined dozens of logic texts and drawn on a wide range of literature to reveal the many uses and misuses of popular opinion. He contrasts the traditional discussion of _ad populum _in Greek rhetoric with recent textbook treatment, then contrasts these contemporary views with his own dialectical perspective in order to clarify often confused appeals to prejudice and appeals to common knowledge. Although appeal to popular opinion has long been a powerful argumentative tactic, this is the first book to systematically describe and evaluate it as a well-defined type of argument with its own special characteristics. It enables us to deal with these often deceptive arguments in a critically balanced way and makes an original contribution to an important strand of rhetoric. (shrink)

The main rationale for adopting the epistemological approach to argumentation seems to take the form of a criticism of the consensus theory. This criticism says that some instances of clearly bad argumentation count as acceptable instances of argumentation on the consensus theory. Supposedly, the epistemological approach does not have this problem. I suggest that the kind of normativity argumentation theorists should be concerned with is the normativity associated with giving real-world advice on how to partake in a critical discussion. I (...) try to show that when we understand the normativity of argumentative standards in this way, the main criticism of the consensus theory falls short, and the epistemological approach does not really have the advantages over the consensus theory that it is purported to have. If I am right, then the main reason offered for adopting the epistemological approach fails, and we should stick with the consensus theory. (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 article outlines a general epistemological theory of argument: a theory that regards providingjustified belief as the principal aim of argumentation, and defends it instrumentalistically. After introducing some central terms of such a theory (2), answers to its central questions are proposed: the primary object and structure of the theory (3), the function of arguments, which is to lead to justified belief (4), the way such arguments function, which is to guide the addressee's cognizing (5), objective versus subjective aspects of (...) argumentation (6), designing different types of argument (7). Then the notion of '(argumentatively) valid argument' is defined and criteria for the adequate use of such arguments are introduced (8). Finally, this conception is justified as, among others, leading to more true beliefs than competing conceptions (9). (shrink)

Brian Huss argues that the consensus theory of argumentation is as good as, or better than, the epistemological approach at giving useful real-world advice about arguments. I describe these two ways of theorizing about arguments, describe the advice that Huss thinks the two theories can offer, make a case largely by means of examples for the view that the epistemological approach does yield useful real world advice, and then formulate and respond to Huss's arguments. I conclude with a few brief (...) comments on consensus and arguments. (shrink)

In this paper we defend a particular version of the epistemic approach to argumentation. We advance some general considerations in favor of the approach and then examine the ways in which different versions of it play out with respect to the theory of fallacies, which we see as central to an understanding of argumentation. Epistemic theories divide into objective and subjective versions. We argue in favor of the objective version, showing that it provides a better account than its subjectivist rival (...) of the central fallacy of begging the question. We suggest that the strengths of the objective epistemic theory of fallacies provide support for the epistemic approach to argumentation more generally. (shrink)