Reasoning

This paper investigates two puzzles in practical reason and proposes a solution to them. First, sometimes, when we are practically certain that neither of two alternatives is better than or as good as the other with respect to what matters in the choice between them, it nevertheless seems perfectly rational to continue to deliberate, and sometimes the result of that deliberation is a conclusion that one alternative is better, where there is no error in one’s previous judgment. Second, there are (...) striking differences between rational agents – some rational agents have most reason to pursue careers on Wall Street while others have most reason to take up a career in teaching, or scuba diving, or working for political causes. These differences aren’t plausibly explained by ‘passive’ facts about our psychology or their causal interaction with our environment; instead, these facts seem in some sense to ‘express who we are’. But what is this sense? These puzzles disappear if we adopt a novel view about the source of the normativity of reasons – some reasons are given to us and others are reasons in virtue of an act of will. We make certain considerations reasons through an act of will and thus sometimes make it true through an act of agency that we have most reason to do one thing rather than another. (shrink)

review of Laden's *Reasoning: a social picture* praising the aim and expressing puzzlement at the details,.

If the cultural variations concerning knowledge and research on ordinary reasoning are part of cultural history, what kind of historiographical method is needed in order to present the history of its evolution? This paper proposes to introduce the study of theories of reasoning into a historiographic perspective because we assume that the answer to the previous question does not only depend of internal controversies about how reasoning performance is explained by current theories of reasoning. [...].

This paper examines precursors and consequents of perceived relevance of a proposition A for a proposition C. In Experiment 1, we test Spohn's assumption that ∆P = P − P is a good predictor of ratings of perceived relevance and reason relations, and we examine whether it is a better predictor than the difference measure − P). In Experiment 2, we examine the effects of relevance on probabilistic coherence in Cruz, Baratgin, Oaksford, and Over's uncertain “and-to-if” inferences. The results suggest (...) that ∆P predicts perceived relevance and reason relations better than the difference measure and that participants are either less probabilistically coherent in “and-to-if” inferences than initially assumed or that they do not follow P = P. Results are discussed in light of recent results suggesting that the Equation may not hold under conditions of irrelevance or negative relevance. (shrink)

Lockheed Martin Corp. has funded research to generate a framework and methodology for developing semantic reasoning applications to support the discipline oflntelligence Analysis. This chapter outlines that framework, discusses how it may be used to advance the information sharing and integrated analytic needs of the Intelligence Community, and suggests a system I software architecture for such applications.

Regress arguments have convinced many that reasoning cannot require beliefs about what follows from what. In this paper I argue that this is a mistake. Regress arguments rest on dubious (although deeply entrenched) assumptions about the nature of reasoning — most prominently, the assumption that believing p by reasoning is simply a matter of having a belief in p with the right causal ancestry. I propose an alternative account, according to which beliefs about what follows from what play a constitutive (...) role in reasoning. (shrink)

In How We Get Along, philosopher David Velleman compares our social interactions to the interactions among improvisational actors on stage. He argues that we play ourselves - not artificially but authentically, by doing what would make sense coming from us as we really are. And, like improvisational actors, we deal with one another in dual capacities: both as characters within the social drama and as players contributing to the shared performance. In this conception of social intercourse, Velleman finds rational grounds (...) for morality, though not a rational guarantee. He maps a middle course between skepticism and rationalism, arguing that practical reasoning is 'pro-moral' without requiring moral action. The result is what he calls a 'Kinda Kantian metaethics'. How We Get Along is the summation of Velleman's thinking to date, incorporating and unifying previous work on agency, the self, the emotions, narrative and Kantian moral theory. (shrink)

This article analyses letters to the editor written on or about Muslims printed in a British broadsheet newspaper. The pragma-dialectical theory of argumentation is applied as a model for explaining and understanding the arguments employed in the sampled letters. Our presentation of pragma-dialectical theory focuses on argumentative reasonableness. More specifically, we introduce the four dialectical stages through which any argument must pass and explain the ten rules of critical discussion that participants must follow throughout if they are to resolve the (...) argument. The article focuses in particular on the letter writers' use of argument schemes-that is, the manner in which these writers use arguments to support their standpoints. We conclude by highlighting the role that unreasonable arguments can play in perpetuating racialized inequalities and hence the importance of analyzing argumentation. (shrink)

Many philosophers subscribe to the view that philosophy is a priori and in the business of discovering necessary truths from the armchair. This paper sets out to empirically test this picture. If this were the case, we would expect to see this reflected in philosophical practice. In particular, we would expect philosophers to advance mostly deductive, rather than inductive, arguments. The paper shows that the percentage of philosophy articles advancing deductive arguments is higher than those advancing inductive arguments, which is (...) what we would expect from the vantage point of the armchair philosophy picture. The results also show, however, that the percentages of articles advancing deductive arguments and those advancing inductive arguments are converging over time and that the difference between inductive and deductive ratios is declining over time. This trend suggests that deductive arguments are gradually losing their status as the dominant form of argumentation in philosophy. (shrink)

This book is written for those who wish to learn some basic principles of formal logic but more importantly learn some easy methods to unpick arguments and assess their value for truth and validity. -/- The first section explains the ideas behind traditional logic which was formed well over two thousand years ago by the ancient Greeks. Terms such as ‘categorical syllogism’, ‘premise’, ‘deduction’ and ‘validity’ may appear at first sight to be inscrutable but will easily be understood with examples (...) bringing the subjects to life. Traditionally, Venn diagrams have been employed to test arguments. These are very useful but their application is limited and they are not open to quantification. The mid-section of this book introduces a methodology that makes the analysis of arguments accessible with the use of a new form of diagram, modified from those of the mathematician Leonhard Euler. These new diagrammatic methods will be employed to demonstrate an addition to the basic form of syllogism. This includes a refined definition of the terms ‘most’ and ‘some’ within propositions. This may seem a little obscure at the moment but one will readily apprehend these new methods and principles of a more modern logic. (shrink)

Abstract Argument is seen as central to philosophy, especially epistemology. It is often said that philosophy teaches you to argue for any position. Arguments are used to justify beliefs and many people suppose that for a belief to be counted for knowledge it must be justified. In science, scientific theories must be backed by the evidence and it has been proposed that the relationship of evidence to theory is that of argument to conclusion. But is argument really so important? Arguments (...) in practice are hardly ever persuasive, and a deductive argument adds no new information. Knowledge and wisdom of the philosophical kind can be garnered and created through observation, exploration, experiment, collaboration, narrative and sharing. None of these ways of knowing necessarily involve argument, and can actually in some cases be harmed by argument. It is fairly uncontroversial to say that argument has a central role in contemporary English speaking philosophy. But if argument is a form of combat then this emphasis on argument could be a source of gender bias in philosophy and in certain sciences. Men are physiologically attracted to combat through the mechanism of testosterone fluctuations in response to competitive situations. But apart from being attractive to some men, arguments do not create good philosophy. Good philosophy aims at the love of wisdom and knowledge. Two principle goods in philosophy are the creation of knowledge and the spreading of knowledge. Arguments neither create knowledge nor are persuasive. On the contrary, arguments create divisions and cognitive biases. As such philosophy may be better with less of an emphasis on argument, and more emphasis on non-violence, sharing and love. (shrink)

Argumentation theory underwent a significant development in the Fifties and Sixties: its revival is usually connected to Perelman's criticism of formal logic and the development of informal logic. Interestingly enough it was during this period that Artificial Intelligence was developed, which defended the following thesis (from now on referred to as the AI-thesis): human reasoning can be emulated by machines. The paper suggests a reconstruction of the opposition between formal and informal logic as a move against a premise of an (...) argument for the AI-thesis, and suggests making a distinction between a broad and a narrow notion of algorithm that might be used to reformulate the question as a foundational problem for argumentation theory. (shrink)

One claim reiterated with increasing boldness by the “analytic” tradition in philosophy is that what sets it apart from long-time rivals is a shared adherence to proper norms of argumentation. Gradated deviancy from this canon by English-speaking practitioners has therefore raised important questions about who can repair under the banner “professional philosopher.” We will portray as deeply worrisome the idea that argumentation should secure not just conclusions, but disciplinary membership as well.

This document provides a brief report on initial research into how argument presentation (visual map vs. regular prose) affects people's susceptibility to confirmation bias as well as their feelings toward political opponents. Using highly polarizing stimuli, we found that argument visualization substantially reduced confirmation bias and, for participants with low CRT scores, the belief that one's political opponents are morally evil.

Judging the warrant of conspiracy theories can be difficult, and often we rely upon what the experts tell us when it comes to assessing whether particular conspiracy theories ought to be believed. However, whereas there are recognised experts in the sciences, I argue that only are is no such associated expertise when it comes to the things we call `conspiracy theories,' but that the conspiracy theorist has good reason to be suspicious of the role of expert endorsements when it comes (...) to conspiracy theories and their rivals. The kind of expertise, then, we might associate with conspiracy theories is largely improvised—in that it lacks institutional features—and, I argue, ideally the product of a community of inquiry. (shrink)

Es werden vier verbreitete Verwendungsweisen des Wortes ‘Argument’ beschrieben, an Beispielen erläutert und dann schrittweise expliziert. Die wichtigsten Explikata sind: ‘eine Satzfolge x ist ein deskriptives Argument in Standardform’, ‘ein deskriptives Argument x in Standardform ist bei der subjektiven Wahrscheinlichkeitsverteilung p stark (bzw. schwach)’, ‘ein Aussagesatz x ist bei der subjektiven Wahrscheinlichkeitsverteilung p ein Argument für (bzw. gegen) einen Aussagesatz y’, ‘ein geordneter Tripel x von deskriptiven Argumenten in Standardform, von Argumentebenen und von Argumentsträngen ist eine deskriptive Argumenthierarchie in Standardform’, (...) ‘eine deskriptive Argumenthierarchie x in Standardform ist gültig (bzw. ungültig; stichhaltig; konsistent; inkonsistent; sichtlich zirkelhaft; stark (bzw. schwach) bei der subjektiven Wahrscheinlichkeitsverteilung p)’. (shrink)

This article presents a comparative theory of subjective argument strength simple enough for application. Using the axioms and corollaries of the theory, anyone with an elementary knowledge of logic and probability theory can produce an at least minimally rational ranking of any set of arguments according to their subjective strength, provided that the arguments in question are descriptive ones in standard form. The basic idea is that the strength of argument A as seen by person x is a function of (...) three factors: x's degree of belief in the premisses of A; x's degree of belief in the conclusion of A under the assumption that all premisses of A are true; and x's belief in the conclusion of A under the assumption that not all premisses of A are true. (shrink)

Does having some feeling or other ever count as an argument – and, should it? As a matter of fact, not just do persons sometimes refer to their feelings to make a point in debate. Often, they even treat them as irrefutable arguments; for they are, of course, certain of their own feelings. To make a point in debate by reference to one’s feelings, one has got to articulate them. As language is the core medium of debate (though it can (...) be supported by images etc.), feelings, then, have to be articulated in words. These words, to function in communication, must participate in what is general (though not necessarily universal). On that level of generality, other speakers of the same language can contest the feelings – not that they have occured within the first speaker’s subjectivity, but that they are reasonable reactions to circumstances. Hence if feeling is sometimes to be taken seriously as an argument, it is not irrefutable, but rather refutable; and to the extent that somebody insists that it is irrefutable, it cannot count as an argument. (shrink)

This textbook is not a textbook in the traditional sense. Here, what we have attempted is compile a set of assignments and exercise that may be used in critical thinking courses. To that end, we have tried to make these assignments as diverse as possible while leaving flexibility in their application within the classroom. Of course these assignments and exercises could certainly be used in other classes as well. Our view is that critical thinking courses work best when they are (...) presented as skills based learning opportunities. We hope that these assignments speak to that desire and can foster the kinds of critical thinking skills that are both engaging and fun Please feel free to contact us with comments and suggestions. We will strive to correct errors when pointed out, add necessary material, and make other additional and needed changes as they arise. Please check back for the most up to date version. Rebeka Ferreira and Anthony Ferrucci. (shrink)

On occasion, someone will ask you why you’re a philosopher and not a scientist or some other, more obviously respectable, intellectual. Or a high and mighty philosopher will dismiss all of philosophy with the exception of the history of philosophy. Others will restrict philosophy’s importance to applied philosophy or philosophy with obvious interdisciplinary features. Or someone from a different discipline might be respectful of the philosophical profession but in need of an explanation of why research in philosophy that is not (...) applied, is not interdisciplinary, and does not fall under the heading of the history of philosophy is thought to be important. A university dean or other university official or professor might have just that question. In fact, your cousin might have that question. (shrink)

One of the central tasks of a theory of argumentation is to supply a theory of appraisal: a set of standards and norms according to which argumentation, and the reasoning involved in it, is properly evaluated. In their most general form, these can be understood as rational norms, where the core idea of rationality is that we rightly respond to reasons by according the credence we attach to our doxastic and conversational commitments with the probative strength of the reasons we (...) have for them. Certain kinds of rational failings are so because they are manifestly illogical – for example, maintaining overtly contradictory commitments, violating deductive closure by refusing to accept the logical consequences of one’s present commitments, or failing to track basing relations by not updating one’s commitments in view of new, defeating information. Yet, according to the internal and empirical critiques, logic and probability theory fail to supply a fit set of norms for human reasoning and argument. Particularly, theories of bounded rationality have put pressure on argumentation theory to lower the normative standards of rationality for reasoners and arguers on the grounds that we are bounded, finite, and fallible agents incapable of meeting idealized standards. This paper explores the idea that argumentation, as a set of practices, together with the procedures and technologies of argumentation theory, is able to extend cognition such that we are better able to meet these idealized logical standards, thereby extending our responsibilities to adhere to idealized rational norms. (shrink)

Corroborative evidence can have a dual function in argument whereby not only does it have a primary function of providing direct evidence supporting the main conclusion, but it also has a secondary, bolstering function which increases the probative value of some other piece of evidence in the argument. It has been argued (Redmayne, 2000) that this double function gives rise to the fallacy of double counting whereby the probative weight of evidence is overvalued by counting it twice. Walton has proposed (...) several models of corroborative evidence, each of which seems to accept the fallaciousness of double counting thereby seeming to deny the dual function of corroborative evidence. Against this view, I argue that the bolstering effect is legitimate, and can be explained by recourse to inference to the best explanation. (shrink)

The paper considers contemporary models of presumption in terms of their ability to contribute to a working theory of presumption for argumentation. Beginning with the Whatelian model, we consider its contemporary developments and alternatives, as proposed by Sidgwick, Kauffeld, Cronkhite, Rescher, Walton, Freeman, Ullmann-Margalit, and Hansen. Based on these accounts, we present a picture of presumptions characterized by their nature, function, foundation and force. On our account, presumption is a modal status that is attached to a claim and has the (...) effect of shifting, in a dialogue, a burden of proof set at a local level. Presumptions can be analysed and evaluated inferentially as components of rule-based structures. Presumptions are defeasible, and the force of a presumption is a function of its normative foundation. This picture seeks to provide a framework to guide the development of specific theories of presumption. (shrink)

This paper offers a probabilistic treatment of the conditions for argument cogency as endorsed in informal logic: acceptability, relevance, and sufficiency. Treating a natural language argument as a reason-claim-complex, our analysis identifies content features of defeasible argument on which the RSA conditions depend, namely: change in the commitment to the reason, the reason’s sensitivity and selectivity to the claim, one’s prior commitment to the claim, and the contextually determined thresholds of acceptability for reasons and for claims. Results contrast with, and (...) may indeed serve to correct, the informal understanding and applications of the RSA criteria concerning their conceptual dependence, their function as update-thresholds, and their status as obligatory rather than permissive norms, but also show how these formal and informal normative approachs can in fact align. (shrink)

We are pleased to publish this WSIA edition of Trudy’s Govier’s seminal volume, Problems in Argument Analysis and Evaluation. Originally published in 1987 by Foris Publications, this was a pioneering work that played a major role in establishing argumentation theory as a discipline. Today, it is as relevant to the field as when it first appeared, with discussions of questions and issues that remain central to the study of argument. It has defined the main approaches to many of those issues (...) and guided the ways in which we might respond to them. From this foundation, it sets the stage for further investigations and emerging research. This is a second edition of the book that is corrected and updated by the author, with new prefaces to each chapter. (shrink)

In this chapter, we outline the range of argument forms involving causation that can be found in everyday discourse. We also survey empirical work concerned with the generation and evaluation of such arguments. This survey makes clear that there is presently no unified body of research concerned with causal argument. We highlight the benefits of a unified treatment both for those interested in causal cognition and those interested in argumentation, and identify the key challenges that must be met for a (...) full understanding of causal argumentation. (shrink)

Contemporary reasoning about health is infused with the work products of experts, and expert reasoning about health itself is an active site for invention and design. Building on Toulmin’s largely undeveloped ideas on field-dependence, we argue that expert fields can develop new inference rules that, together with the backing they require, become accepted ways of drawing and defending conclusions. The new inference rules themselves function as warrants, and we introduce the term “warranting device” to refer to an assembly of the (...) rule plus whatever material, procedural, and institutional resources are required to assure its dependability. We present a case study on the Cochrane Review, a new method for synthesizing evidence across large numbers of scientific studies. After reviewing the evolution and current structure of the device, we discuss the distinctive kinds of critical questions that may be raised around Cochrane Reviews, both within the expert field and beyond. Although Toulmin’s theory of field-dependence is often criticized for its relativism, we find that, as a matter of practical fact, field-specific warrants do not enjoy immunity from external critique. On the contrary, they can be opened to evaluation and critique from any interested perspective. (shrink)

What’s wrong with begging the question? Some philosophers believe that question-begging arguments are inevitably fallacious and that their fallaciousness stems from a shared “formal” deficiency. In contrast, some philosophers, like Robinson deny that begging the question is fallacious at all. And others characterize begging the question as an “informal” fallacy of reasoning that can only be understood with the aid of epistemic notions. Sorensen joins this last camp by offering a powerful argument against both Robinson’s skepticism and fully formal approaches (...) to the phenomenon. According to Sorensen’s view, question-begging is fallacious because it compromises the rationality of the question-beggar’s position. Though his argument forces Robinson into a peculiar dialectical position, it does little to elucidate the reasons why Robinson’s position is unstable and it fails to embody Sorensen’s own conception of rationally persuasive argumentation. I utilize this conception to show how Robinson is left with no easily identifiable grounds on which to deny the fallaciousness of begging the question. By advancing the dialectic between Sorensen and Robinson, I aim to show that our argumentative practices must take the perspectives of others seriously, whether or not those perspectives are rational. (shrink)

Die Transzendentalpragmatik beansprucht, jeden beliebigen Opponenten, der bestimmte nichtverwerfbare Präsuppositionen des Argumentierens bestreitet, eines performativen Selbstwiderspruchs überführen zu können. Die Diagnose performativer Widersprüche ist indes theoretisch voraussetzungsreich, denn sie findet in einem begrifflichen Rahmen statt, der sich aus nichttrivialen sprechakt-, rationalitäts-, bedeutungs- und argumentationstheoretischen Annahmen zusammensetzt. Das Argument einer anderen möglichen Vernunft ist gegen den Letztbegründungsanspruch der Transzendentalpragmatik gerichtet: Was heute als ein performativer Widerspruch zählt, mag aus der Perspektive einer anderen möglichen Vernunft keiner mehr sein. Im Beitrag wird die (...) Relevanz des Einwands einer anderen möglichen Vernunft bestritten. Der Nachweis der aktuellen Nichtverwerfbarkeit einer Präsupposition des Argumentierens braucht die Revidierbarkeit des begrifflichen und rationalitätstheoretischen Rahmens nicht auszuschließen. Mithilfe einer messtheoretischen Analogie wird gezeigt, dass die Revision eines Rahmens im alten Rahmen formulierte Aussagen ebensowenig falsch macht wie die Veränderung eines Maßstabs frühere Messungen. -/- . (shrink)

In this paper, the political pamphlet “Der Hessische Landbote” by the eminent German author, Georg Büchner (1813–1837), will be positioned within the context of its political and historical background, analyzed as to its argumentative and stylistic structure, and critically evaluated. It will be argued that propaganda texts such as this should be evaluated by taking into account both rhetorical perspectives and standards of rational discussion. As far as argumentative structure is concerned, a modified version of the Toulmin scheme will be (...) used for the description of three passages of the “Landbote”. As far as stylistic techniques are concerned, Büchner’s strategic use of some figures of speech, especially parallelism, metaphor and metonymy will be examined. As to the critical evaluation, the recently developed concept of “strategic maneuvering” within Pragma-Dialectics, the typology of argumentative dialogues established by D. Walton, and sets of critical questions will be used to assess the status of the arguments within the “Landbote” as potentially fallacious ones. (shrink)

Descartes and Architecture -/- The article analyses the architectural metaphor in Descartes' Discourse on Method and The Seventh replies. The idea of Descartes' project, introduced to the reader as a construction of a building and planning of a city, is much more indebted to its architectural imagery than, or so its critics say, is "sound" for a philosophical theory. Architecture is an analogon of philosophy in Descartes' texts. By producing a figure of philosopher-architect, Descartes tries to legitimate his philosophical theory (...) using architectural discourse. Descartes always uses the examples of architecture and urban planning when he intends to introduce his great project of a new beginning in philosophy. This new beginning is manifest in two levels: first, as a denial of traditional metaphysics of the Schools in the Discourse, and second, as a denial of one’s own beliefs in the Meditations using methodical doubt. In the conclusion, the article emphasises through Derrida's analysis of metaphor that, given the metaphysical nature of any metaphor, Descartes’ metaphor also cannot appear as a mere rhetorical figure. (shrink)

Mit großer Wahrscheinlichkeit wird die Alternative für Deutschland (AfD) am 24. September in den Bundestag einziehen. Jüngste Umfragen legen nahe, dass sie sogar drittstärkste Partei werden könnte. Warum findet die AfD so viele Unterstützerinnen und Unterstützer? Mit welchen Argumenten wirbt die AfD für ihren Einzug in den Bundestag? Das Wahlprogramm der AfD zeigt nicht nur, wofür die Partei steht, sondern auch welche Strategie sie bei der Bundestagswahl und darüber hinaus verfolgt. Aus diesem Grund habe ich es argumentationstheoretisch analysiert und die (...) darin enthaltene Argumentation im Detail rekonstruiert. Die wichtigsten Ergebnisse umfassen: Erstens, aus einer rein logischen Perspektive ist die Argumentation der AfD außergewöhnlich klar und stringent. Dies gelingt ihr deshalb, weil sie sich gezielt auf Annahmen stützt, die vereinfachend oder konstruiert sind. Zweitens, das zentrale Thema der „Flüchtlingskrise“ zieht sich beinahe durch die gesamte Argumentation. Es taucht in Argumenten über den Verlust der Leitkultur oder den Verfall der inneren Sicherheit genauso auf wie in Argumenten über die Folgen der Globalisierung oder den demographischen Wandel. Drittens, und dies ist das zentrale Ergebnis der Analyse, die AfD argumentiert nach dem folgenden Muster: Es gibt eine Bedrohung. Nur die AfD kann uns davor bewahren. Also muss die AfD an die Macht kommen. Dies nenne ich das „Kernargument des Populismus“. (shrink)

Despite the effort educators put into developing in students the critical writing and thinking skills needed to compose effective arguments, undergraduate college students are often accused of churning out essays lacking in creative and critical thought, arguments too obviously formulated and with sides too sharply drawn. Theories abound as to why these deficiencies are rampant. Some blame students’ immature cognitive and emotional development for these lacks. Others put the blame of lackadaisical output on the assigning of shopworn writing subjects, assigned (...) topics such as on American laws and attitudes about capital punishment and abortion. Although these factors might contribute to faulty written output in some cases, the prevailing hindrance is our very pedagogy, a system in which students are rewarded for composing the very type of argument we wish to avoid — the eristic, in which the goal is not truth seeking, but successfully disputing another’s argument. Certainly the eristic argument is the intended solution in cases when a clear‑cut outcome is needed, such as in legal battles and political campaigns when there can only be one winner. However, teaching mainly or exclusively the eristic, as is done in most composition classrooms today, halts the advancement of these higher‑order inquiry skills we try developing in our students. (shrink)

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.

This paper explains how to use a new software tool for argument diagramming available free on the Internet, showing especially how it can be used in the classroom to enhance critical thinking in philosophy. The user loads a text file containing an argument into a box on the computer interface, and then creates an argument diagram by dragging lines from one node to another. A key feature is the support for argumentation schemes, common patterns of defeasible reasoning historically know as (...) topics . Several examples are presented, as well as the results of an experiment in using the system with students in a university classroom. (shrink)

Presumption is a complex concept in law, affecting the dialogue setting. However, it is not clear how presumptions work in everyday argumentation, in which the concept of “plausible argumentation” seems to encompass all kinds of inferences. By analyzing the legal notion of presumption, it appears that this type of reasoning combines argument schemes with reasoning from ignorance. Presumptive reasoning can be considered a particular form of reasoning, which needs positive or negative evidence to carry a probative weight on the conclusion. (...) For this reason, presumptions shift the burden of providing evidence or explanations onto the interlocutor. The latter can provide new information or fail to do so: whereas in the first case the new information rebuts the presumption, in the second case, the absence of information that the interlocutor could reasonably provide strengthen the conclusion of the presumptive reasoning. In both cases the result of the presumption is to strengthen the conclusion of the reasoning from lack of evidence. As shown in the legal cases, the effect of presumption is to shift the burden of proof to the interlocutor; however, the shift a presumption effects is only the shift of the evidential burden, or the burden of completing the incomplete knowledge from which the conclusion was drawn. The burden of persuasion remains on the proponent of the presumption. On the contrary, reasoning from definition in law is a conclusive proof, and shifts to the other party the burden to prove the contrary. This crucial difference can be applied to everyday argumentation: natural arguments can be divided into dialectical and presumptive arguments, leading to conclusions materially different in strength. -/- . (shrink)

We argue that common knowledge, of the kind used in reasoning in law and computing is best analyzed using a dialogue model of argumentation (Walton & Krabbe 1995). In this model, implicit premises resting on common knowledge are analyzed as endoxa or widely accepted opinions and generalizations (Tardini 2005). We argue that, in this sense, common knowledge is not really knowledge of the kind represent by belief and/or knowledge of the epistemic kind studied in current epistemology. This paper takes a (...) different approach, defining it in relation to a common commitment store of two participants in a rule-governed dialogue in which two parties engage in rational argumentation (Jackson & Jacobs 1980; van Eemeren & Grootendorst 2004). A theme of the paper is how arguments containing common knowledge premises can be studied with the help of argumentation schemes for arguments from generally accepted opinion and expert opinion. It is argued that common knowledge is a species of provi- sional acceptance of a premise that is not in dispute at a given point in a dia- logue, but may later be defeated as the discussion proceeds . (shrink)

This paper engages with Svavar Svavarsson’s recent essay, “Sextus Empiricus on Persuasiveness and Equipollence,” arguing against both (i) his interpretation of whether two rival arguments appear equipollent to the Pyrrhonist because he himself is equally persuaded by both of them, and (ii) his interpretation of the way in which the argument from possible disagreement is supposed to induce suspension of judgment in the Pyrrhonist. In so doing, I aim to dispel some serious misunderstandings regarding key aspects of the Pyrrhonist’s skeptical (...) outlook and argumentative practice. (shrink)

I provide a critical survey of some of the major findings of Wittgenstein and Searle on the logical structure of intentionality (mind, language, behavior), taking as my starting point Wittgenstein’s fundamental discovery –that all truly ‘philosophical’ problems are the same—confusions about how to use language in a particular context, and so all solutions are the same—looking at how language can be used in the context at issue so that its truth conditions (Conditions of Satisfaction or COS) are clear. The basic (...) problem is that one can say anything but one cannot mean (state clear COS for) any arbitrary utterance and meaning is only possible in a very specific context. I begin with ‘On Certainty’ and continue the analysis of recent writings by and about them from the perspective of the two systems of thought, employing a new table of intentionality and dual systems nomenclature. (shrink)

In this paper, I reply to Seidel’s objections against my argument from expert performance to the effect that arguments from expert opinion are weak arguments. I clarify what Seidel takes to be unclear points in my argument and show that it withstands Seidel’s objections.

In this paper, I sketch an answer to the question “Why be an intellectually humble philosopher?” I argue that, as far as philosophical argumentation is concerned, the historical record of Western Philosophy provides a straightforward answer to this question. That is, the historical record of philosophical argumentation, which is a track record that is marked by an abundance of alternative theories and serious problems for those theories, can teach us important lessons about the limits of philosophical argumentation. These lessons, in (...) turn, show why philosophers should argue with humility. (shrink)

In this paper, I argue that, other things being equal, simpler arguments are better. In other words, I argue that, other things being equal, it is rational to prefer simpler arguments over less simple ones. I sketch three arguments in support of this claim: an argument from mathematical proofs, an argument from scientific theories, and an argument from the conjunction rule.

In this paper, I argue that, contrary to common opinion, a counterexample against a philosophical theory does not amount to conclusive evidence against that theory. Instead, the method of counterexamples allows for the derivation of a disjunction, i.e., ‘either the theory is false or an auxiliary assumption is false’, not a negation of the target theory. This is so because, whenever the method of counterexamples is used in an attempt to refute a philosophical theory, there is a crucial auxiliary assumption (...) that needs to be taken into account. The auxiliary assumption is that making intuitive judgments in response to hypothetical cases about the subject matter in question (e.g., knowledge or proper names) is a good method for finding out truths about that subject matter. Without good reasons to think that this assumption is warranted, the negation of a philosophical theory whose content is alleged to be in conflict with the content of an intuition cannot be justifiably derived using an argument that employs the method of counterexamples. (shrink)