Fallacies

The standard definition of “argument” is satisfied by any series of statements in which one (of the statements) is marked as the conclusion of the others. This leads to the counter-intuitive result that “I like cookies, therefore, all swans are white” is an argument, since “therefore” marks “all swans are white” as the conclusion of “I like cookies”. This objection is often disregarded by stating that, although the previous sequence is an argument, it fails to be a good one. However, (...) when we compare our previous argument with a definitely bad argument like “this swan is white, therefore, all swans are white”, we see that there is an important difference between them. Whereas the former fails to fulfil our intuition of what an argument is, the latter does qualify as an argument, but as a bad one. In this talk, I will sketch a definition that better captures this feature of our intuition of what an argument is in three steps. Following Díez and Moulines (1999), I first reduce inductive validity to deductive validity through what we may call the method of deductivisation. Second, through epistemic predicates (cf. Thompson 2002), I introduce a broader concept of validity that accounts not only for deductive and inductive validity, but also for a weaker type of validity that may be called pseudo-validity. I show that these pseudo-valid arguments can also be deductivised with the help of the above-mentioned epistemic predicates. Finally, I re-define the concept of argument as any series of statements that is at least pseudo-valid, which leaves the “cookies argument” outside of this definition. (shrink)

There is almost a consensus among conditional experts that indicative conditionals are not material. Their thought hinges on the idea that if indicative conditionals were material, A → B could be vacuously true when A is false, even if B would be false in a context where A is true. But since this consequence is implausible, the material account is usually regarded as false. It is argued that this point of view is motivated by the grammatical form of conditional sentences (...) and the symbols used to represent their logical form, which misleadingly suggest a one-way inferential direction from A to B. That conditional sentences mislead us into a directionality bias is a phenomenon that is well-documented in the literature about conditional reasoning. It is argued that this directional appearance is deceptive and does not reflect the underlying truth conditions of conditional sentences. This directional bias is responsible for both the unpopularity of the material account of conditionals and some of the main alternative principles and themes in conditional theory, including the Ramsey’s test, the Equation, Adams’ thesis, conditional-assertion and possible world theories. The directional mindset forgets a hard- earned lesson that made classical logic possible in the first place, namely, that grammatical form of sentences can mislead us about its truth conditions. There is a case to be made for a material account of indicative conditionals when we break the domination of words over the human mind. (shrink)

The tradition of Nyāya philosophy centers on a dispassionate quest for truth which is simultaneously connected to soteriological and epistemic aims. In this paper, I show how Vācaspati Miśra brings together the soteriological concept of dispassion (vītarāga) with the discourse practices of debate (kathā), as a response to Buddhist criticisms in Dharmakīrti’s Vādanyāya. He defends the Nyāyasūtra’s stated position that fallacious reasoning is a legitimate means for a debate, under certain circumstances. Dharmakīrti argues that such reasoning is rationally ineffective and (...) indicates unvirtuous qualities. For Vācaspati, fallacies are a way to prevent the spread of morally weighty falsehoods when no other method is available to a debater. After showing textual relationships between Vācaspati’s defense and Dharmakīrti’s earlier criticism, I evaluate their arguments, concluding that Vācaspati’s position involves irresolvable tensions with other Nyāya commitments. (shrink)

In this paper, I study the relation between arguments against the person (aka ad hominem or personal attack arguments) and disqualifications for conflicts of interests. I show that both types of arguments share a similar logical structure and that they can be considered to be acceptable in similar circumstances.

In the last decades Human-Computer Interaction (HCI) has started to focus attention on “persuasive technologies” having the goal of changing users’ behavior and attitudes according to a predefined direction. In this talk we show how some of the techniques employed in such technologies trigger some well known cognitive biases by adopting a strategy relying on logical fallacies (i.e. forms of reasoning which are logically invalid but psychologically persuasive). In particular, we will show how the mechanisms reducible to logical fallacies are (...) used to design web and mobile interfaces in domains ranging from the e-commerce to the jihadist propaganda. The final part of the talk will be devoted to point out the potential ethical dangers related to the misuse of these techniques in the design of persuasive technologies. (shrink)

The global emergency caused by the spread of COVID-19 raises critical challenges for individuals and communities on many different levels. In particular, politicians, scientists, physicians, and other professionals may face new ethical dilemmas and cognitive constraints as they make critical decisions in extraordinary circumstances. Philosophers and cognitive scientists have long analyzed and discussed such issues. An example is the debate on moral decision making in imaginary scenarios, such as the famous “Trolley Problem”. Similarly, dramatic and consequential decisions are realized daily (...) in the current crisis. Focusing on Italy, we discuss the clinical ethical guidelines proposed by the Italian Society of Anesthesiology, Analgesia, Resuscitation and Intensive Care, highlighting some crucial ethical and cognitive concerns surrounding emergency decision making in the current situation. (shrink)

Jeśli można mówić o modzie w badaniach naukowych, to semantyka jest od prawie wieku niewątpliwie jedną z bardziej modnych dziedzin w nauce. Badają ją nie tylko logicy i filozofowie języka, lecz także kulturoznawcy, antropologowie, filologowie, kognitywiści czy informatycy. Niniejszy artykuł ma na celu zbadanie roli, jaką odgrywa semantyka w teorii argumentacji, a dokładniej — zarysowanie pewnego modelu argumentacji, który modyfikuje znaczenia terminów dla celów argumentacyjnych. Najpierw przedstawię kilka przykładowych argumentów semantycznych, analizując każdy z nich na tyle, aby wydobyć pewne subtelności (...) potrzebne do zbudowania modelu argumentu semantycznego. W ten sposób pokażę, jak nomen omen znaczący wpływ na argumentację ma znaczenie słów, a także na ile sposobów może ono wpływać na przebieg argumentacji. Na samym końcu zarysuję definicję argumentu semantycznego, która może wytyczyć kierunek dalszych badań nad semantyką w teorii argumentacji. (shrink)

Objetivamos discutir a crítica, avançada por Colin Howson em Hume's problem, segundo a qual o argumento do milagre (doravante, AM) comete a falácia da taxa-base. Por falácia da taxa-base, entende-se a negligência do valor da probabilidade prévia de determinada hipótese ou teoria T, P(T). Por sua vez, em uma de suas versões, AM assere que apenas assumindo que uma teoria científica madura T é aproximadamente verdadeira não faz de seu sucesso preditivo um milagre. Formalizado probabilisticamente, Howson argumenta que a conclusão (...) de AM, a probabilidade de que a teoria T seja aproximadamente verdadeira é grande, apenas se segue se assumirmos para T um valor não-negligenciável. Tal crítica de Howson despertou duas categorias de reação na literatura especializada: supondo que AM comete a falácia da taxa base, alguns autores propuseram abandonar AM enquanto um argumento para a tese epistemológica do realismo científico, ao passo que outros defenderam que apenas uma versão de AM comete a falácia da taxa-base; defendendo que AM não comete a falácia da taxa base, certos autores alegaram alguns problemas na formalização probabilística de AM, enquanto outros buscaram refinar tal formalização de modo que a nova evite a falácia em questão. Tendo apresentado esse estado da arte, investigaremos se a formalização probabilística do argumento do milagre é razoável. Discutiremos se ela acomoda a natureza de inferência à melhor explicação pressuposta no AM. Por fim, indicaremos, brevemente, algumas dificuldades para a crítica de Howson ao assumir-se que AM instancia, na verdade, uma abdução Peirceana. (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)

ABSTRACTIn order to explain the effects found in the heuristics and biases literature, dual-process theories of reasoning claim that human reasoning is of two kinds: Type-1 processing is fast, automatic, and associative, while Type-2 reasoning is slow, controlled, and rule based. If human reasoning is so divided, it would have important consequences for morality, epistemology, and philosophy of mind. Although dual-process theorists have typically argued for their position by way of an inference to the best explanation, they have generally failed (...) to consider alternative hypotheses. Worse still, it is unclear how we might test dual-process theories. In this article, I offer a one-system theory, which I call the Sound-Board Account of Reasoning, according to which there is one reasoning system which is flexible, allowing the properties used to distinguished Type-1 and Type-2 reasoning to cross-cut one another. I empirically distinguish my theory from the two dominant versions of dual-process theory (parallel... (shrink)

This paper explains a fallacy that often arises in theorizing about human minds. I call it the Factual Belief Fallacy. The Fallacy, roughly, involves drawing conclusions about human psychology that improperly ignore the large backgrounds of mostly accurate factual beliefs people have. The Factual Belief Fallacy has led to significant mistakes in both philosophy of mind and cognitive science of religion. Avoiding it helps us better see the difference between factual belief and religious credence; seeing that difference in turn enables (...) us to pose interesting normative questions about various mental states labeled “belief.”. (shrink)

Plausibly, an inference is an act of coming to believe something on the basis of something else you already believe. But what is it to come to believe some- thing on the basis of something else? I propose a disjunctive answer: it is either for some beliefs to rationally cause another—where rational causation is understood as causation that is either actually or potentially productive of knowledge—or for some beliefs to “deviantly” cause another, but for the believer mistakenly to come thereby (...) to believe that the former have rationally caused the latter. The result, I argue, is both a theoretically satisfying account of the act of inferring and a demonstration of the power of a knowledge-first approach to the philosophy of mind. (shrink)

I present three critical points against G.E.R. Lloyd's ‘The Fortunes of Analogy’. First, I argue that Lloyd unduly criticises Aristotle's view of analogies. Second, I argue that Lloyd needs to discuss the means of limiting the semantic stretch of terms, for instance through the distinction between fiat and bona fide boundaries. Third, I point out some terminological issues in Lloyd's account, especially concerning the applicability of validity, soundness, and fallaciousness to analogies.

According to Thagard, the behavior of practitioners of a field may also be used for demarcation between science and pseudoscience due to its social dimension in addition to the epistemic one. I defended the tendency of pseudoscientists to commit fallacies, and the number of fallacies they commit can be a secondary tool for demarcation problem and this tool is consistent with Thagardian approach. In this paper, I selected the astrology as the case and I revealed nine types of logical fallacies (...) frequently committed by astrologers while introducing their field and/or defending their claims against the scientific inquiries and refutation efforts. I also argued that recognizing these fallacies may help the audience to demarcate between the scientific and the pseudoscientific arguments. (shrink)

What should a virtue theory of argumentation say about fallacious reasoning? If good arguments are virtuous, then fallacies are vicious. Yet fallacies cannot just be identified with vices, since vices are dispositional properties of agents whereas fallacies are types of argument. Rather, if the normativity of good argumentation is explicable in terms of virtues, we should expect the wrongness of bad argumentation to be explicable in terms of vices. This approach is defended through analysis of several fallacies, with particular emphasis (...) on the ad misericordiam. (shrink)

Research into the cognition of conditionals has predominantly focused on conditional reasoning, producing a range of theories which explain associated phenomena with considerable success. However, such theories have been less successful in accommodating experimental data concerning how agents assess the probability of indicative conditionals. Since an acceptable account of conditional reasoning should be compatible with evidence regarding how we evaluate conditionals’ likelihoods, this constitutes a failing of such theories. Section 1 introduces the most dominant established approach to conditional reasoning: mental (...) models theory. Surveying a range of experimental results, I show that mental models theory (along with competing theories) is incapable of fully accounting for findings regarding judgements about conditionals’ probabilities. Section 2 introduces an alternative account of deductive reasoning, the erotetic theory, recently proposed by Koralus and Mascarenhas (2013). Section 3 argues that, given a natural extension, this theory is able to explain the otherwise unaccounted for data. (shrink)

According to an argument by Colin Howson, the no-miracles argument is contingent on committing the base-rate fallacy and is therefore bound to fail. We demonstrate that Howson’s argument only applies to one of two versions of the NMA. The other version, which resembles the form in which the argument was initially presented by Putnam and Boyd, remains unaffected by his line of reasoning. We provide a formal reconstruction of that version of the NMA and show that it is valid. Finally, (...) we demonstrate that the use of subjective priors is consistent with the realist implication of the NMA and show that a core worry with respect to the suggested form of the NMA can be dispelled. (shrink)

: In this paper we examine two challenges to the orthodox understanding of the fallacy of denying the antecedent. One challenge is to say that passages thought to express the fallacy can usually be given an interpretation on which they express valid arguments, entitling us to query whether the fallacy is commonly, if ever, committed at all. We discuss this claim in Section 1. The second challenge comes from those who think that there are legitimate uses of denying the antecedent (...) that have traditionally been overlooked. In Section 2 we propose a general test for claims of this sort, and assess three versions of this view. (shrink)

Throughout the history of analytic philosophy the notion of the ‘phenomenological fallacy’ originally formulated by Place, has been used to criticize reification of the mental. Although this fallacy was originally not used to criticize the phenomenological tradition, it has popped up recently in debates between analytic philosophers and phenomenologists. However, a study of the history of both traditions reveals that a polemical notion similar, if not identical, to the phenomenological fallacy can be found within the phenomenological tradition, namely Sartre’s ‘illusion (...) of immanence’. In this article, I will explicate these two polemical notions and place them in the context of their respective traditions. This will reveal that both notions must be understood as a criticism of a certain form of representationalism I will call ‘dual-world representationalism’. This deep-rooted similarity between the analytic philosophy of mind and phenomenology, in turn, sheds a new light on current discussions between the two traditions. (shrink)

Many of us read Peter Singer ’ s work on our obligations to those in desperate need with our students. Famously, Singer argues that we have a moral obligation to give a significant portion of our assets to famine relief. If my own experience is not atypical, it is quite common for students, upon grasping the implications of Singer ’ s argument, to ask whether Singer gives to famine relief. In response it might be tempting to remind students of the (...) ad hominem fallacy of attacking the person advancing an argument rather than the argument itself. In this paper I argue that the “ ad hominem reply ” to students ’ request for information about Singer is misguided. First I show that biographical facts about the person advancing an argument can constitute indirect evidence for the soundness / unsoundness of the argument. Second, I argue that such facts are relevant because they may reveal that one can discard the argument without thereby incurring moral responsibility for failing to act on its conclusion even if the argument is sound. (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 response to the claim that the properties typically used to distinguish System 1 from System 2 crosscut one another, Carruthers, Evans, and Stanovich have abandoned the System 1/System 2 distinction. Evans and Stanovich both opt for a dual-process theory, according to which Type-1 processes are autonomous and Type-2 processes use working memory and involve cognitive decoupling. Carruthers maintains a two-system account, according to which there is an intuitive system and a reflective system. I argue that these defenses of dual-process (...) theory face two problems. First, as pointed out by Sloman, these new dual-process theories cast the net of “reasoning” too wide. Second, and more importantly, this singular distinction cannot accomplish the explanatory work needed to support dual-process theory. These theorists must fall back on using various properties from the Standard Menu in explanations, thereby committing these accounts to a “Standard View” that they had hoped to avoid. Thus, these theorists face a.. (shrink)

This paper considers whether universally—for all (known) rational beings—an argument scheme or pattern can go from being cogent (well-reasoned) to fallacious. This question has previously received little attention, despite the centrality of the concepts of cogency, scheme, and fallaciousness. I argue that cogency has vanished in this way for the following scheme, a common type of impersonal means-end reasoning: X is needed as a basic necessity or protection of human lives, therefore, X ought to be secured if possible. As it (...) stands (with no further elaboration), this scheme is committed to the assumption that the greater the number of human lives, the better. Although this assumption may have been indisputable previously, it is clearly disputable now. It is a fallacy or non sequitur to make a clearly disputable assumption without providing any justification. Although this topic raises critical issues for practically every discipline, my primary focus is on logical (as opposed to empirical or ethical) aspects of the case, and on implications for practical and theoretical logic. I conclude that the profile of vanishing cogency of the scheme may be unique and is determined by a peculiar combination of contingent universality and changing conditions. (shrink)

What do you get when you cross a fallacy with a good argument? A fugu, that is, a valid argument that tempts you to reach its conclusion invalidly. You have yielded to the temptation more than you realize. If you are a teacher, you may have served many fugus. They arise systematically through several mechanisms. Fugus are interesting intermediate cases that shed light on the following issues: bare evidentialism, false pleasure, philosophy of education, and the ethics of argument. Normally, a (...) fugu will not yield knowledge from known premises. But if the reasoning is only slightly fallacious, they do yield knowledge. These mild fugus show that we can gain knowledge by invalid reasoning. This is a conservative resource for historians. They want to credit discoveries to Euclid rather than those who made minor corrections to his proofs, such as David Hilbert. We also benefit from this practice of grandfathering in old standards of knowledge attribution. For we can compete spiritedly for priority. We do not need to worry that credit will instead go to future scholars who will make the minor amendments needed to raise present proofs to a future standard of demonstration. (shrink)

Argumentation theorists are beginning to think of ad hominem arguments as generally legitimate. Virtue argumentation theorists argue that a character trait approach to argument appraisal can explain why ad hominems would are legitimate, when they are legitimate. But I argue that we do not need to appeal to virtue argumentation theory to explain the legitimacy of ad hominem arguments; a more straightforward evidentialist approach to argument appraisal is also committed to their legitimacy. I also argue that virtue argumentation theory faces (...) some important problems, and that whereas the virtue-theoretic approach in epistemology is well-motivated, that motivation does not carry over to virtue argumentation theory. (shrink)

Public health communication makes extensive use of a linguistic formulation that will be called the “no evidence” statement. This is a written or spoken statement of the form “There is no evidence that P” where P stands for a proposition that typically describes a human health risk. Danger lurks in these expressions for the hearer or reader who is not logically perspicacious, as arguments that use them are only warranted under certain conditions. The extent to which members of the public (...) are able to determine what those conditions are will be considered by examining data obtained from 879 subjects. The role of “no evidence” statements as cognitive heuristics in public health reasoning is considered. (shrink)

We have noticed a pattern of arguments that exhibit a type of irrationality or a particular informal logical fallacy that is not fully captured by any existing fallacy. This fallacy can be explored through three examples where one misattributes a cause by focusing on a smaller portion of a larger set—specifically, the last or least known—and claiming that that cause holds a unique priority over other contributing factors for the occurrence of an event. We propose to call this fallacy the (...) “last straw fallacy” and will argue why these examples actually warrant a new logical name. Finally, we will show how these cases point to a deeper insight about the contexts in which we typically invoke this type of reasoning and some significant harmful consequences of doing so. (shrink)

Recent work on conditional reasoning argues that denying the antecedent [DA] and affirming the consequent [AC] are defeasible but cogent patterns of argument, either because they are effective, rational, albeit heuristic applications of Bayesian probability, or because they are licensed by the principle of total evidence. Against this, we show that on any prevailing interpretation of indicative conditionals the premises of DA and AC arguments do not license their conclusions without additional assumptions. The cogency of DA and AC inferences rather (...) depends on contingent factors extrinsic to, and independent of, what is asserted by DA and AC arguments. arguments do not license their conclusions without additional assumptions. The cogency of DA and AC inferences rather depends on contingent factors extrinsic to, and independent of, what is asserted by DA and AC arguments. (shrink)

What if in discussion the critic refuses to recognize an emotionally expressed argument of her interlocutor as an argument, accusing him of having presented no argument at all. In this paper, we shall deal with this reproach, which taken literally amounts to a charge of having committed a fallacy of non-argumentation. As such it is a very strong, if not the ultimate, criticism, which even carries the risk of abandonment of the discussion and can, therefore, not be made without burdening (...) oneself with correspondingly strong obligations. We want to specify the fallacies of non-argumentation and their dialectic, i.e., the proper way to criticize them, the appropriate ways for the arguer to react to such criticism, and the appropriate ways for the critic to follow up on these reactions. Among the types of fallacy of non-argumentation, the emphasis will be on the appeal to popular sentiments . Our aim is to reach, for cases of non-argumentation, a survey of dialectical possibilities. By making the disputants themselves responsible for the place of emotion in their dialogues, we hope to contribute to a further development of the theory of dialectical obligations. (shrink)

The aim of the paper is to explore the interrelation between persuasion tactics and properties of speech acts. We investigate two types of arguments ad: ad hominem and ad baculum. We show that with both of these tactics, the structures that play a key role are not inferential, but rather ethotic, i.e., related to the speaker’s character and trust. We use the concepts of illocutionary force and constitutive conditions related to the character or status of the speaker in order to (...) explain the dynamics of these two techniques. In keeping with the research focus of the Polish School of Argumentation, we examine how the pragmatic and rhetorical aspects of the force of ad hominem and ad baculum arguments exploit trust in the speaker’s status to influence the audience’s cognition. (shrink)

In order to promote more gracious and productive faith-science dialogue, this communication examines five pitfalls that it can be helpful to avoid.

The public must make assessments of a range of health-related issues. However, these assessments require scientific know-ledge which is often lacking or ineffectively utilized by the public. Lay people must use whatever cognitive resources are at their disposal to come to judgement on these issues. It will be contended that a group of arguments—so-called informal fallacies—are a valuable cognitive resource in this regard. These arguments serve as cognitive heuristics which facilitate reasoning when knowledge is limited or beyond the grasp of (...) reasoners. The results of an investigation into the use of these arguments by the public are reported. (shrink)

The naturalistic fallacy according to Moore and its relation to Hume will be analyzed for an exposition both clear and updated in contemporary formal logics, which will denounce its limited scope in current metaethics. I’ll identify the origins of the expression naturalistic fallacy in Moore and atempt to refne its meaning and use, contrasting its relationship to the open-question argument and Hume’s Law. Its application is identifed in four aspects: invalidly as the openquestion argument for not establishing a metaphysical connection (...) and providing false cognates, and validly as a categorical error, a misidentifcation error and an inferential error; this last one relatable with Hume’s Law as a procedural argumentation error. Brief applications show the limits of the naturalistic fallacy in that, contradictorily, it isn’t a fallacy but by one of its uses, as well as not rebuting every naturalistic theory (as hedonism and utilitarianism) besides being also an argument in favor of some (non-cognitivists). (shrink)

Epistemic Reasoning and the Mental integrates the epistemology of reasoning and philosophy of mind. The book contains introductions to basic concepts in the epistemology of inference and to important aspects of the philosophy of mind. By examining the fundamental competencies involved in reasoning, Gerken argues that reasoning's epistemic force depends on the external environment in ways that are both surprising and epistemologically important. -/- For example, Gerken argues that purportedly deductive reasoning that exhibits the fallacy of equivocation may nevertheless transmit (...) epistemic warrant from its premise-beliefs to its conclusion-belief. This view is contrary to orthodoxy according to which such reasoning must be valid. But Gerken shows how this novel and unorthodox view is integrated in a psychologically plausible account of our reasoning competencies and a general epistemological framework. -/- What emerges is an approach to the philosophy of reasoning that is informed and constrained by both epistemology and philosophy of mind. -/- . (shrink)

In 1685, in The Art of Discovery, Leibniz set down an extraordinary idea: "The only way to rectify our reasonings is to make them as tangible as those of the Mathematicians, so that we can find our error at a glance, and when there are disputes among persons, we can simply say: Let us calculate [calculemus], without further ado, to see who is right." Calculemus.

In this paper I develop an account of petitio principii (the fallacy sometimes also called ‘vicious circularity’, or ‘begging the question’) which has two crucial features: it employs the notion of doxastic justification, and it takes circularity to be relative to an evidential state. According to my account, an argument will be circular relative to an evidential state if and only if having doxastic justification for the conclusion is necessary, for a subject in that evidential state, to have doxastic justification (...) for the premisses. I compare the account to some existing ones, and claim some advantages. I then rebut an objection which threatens to undermine the importance of one of those advantages. This account seems to shed new light on the old problem of characterizing petitio principii. It avoids the two obvious problems which any account of this phenomenon must face: being too narrow, for example by leaving out all arguments in which the conclusion does not appear among the premisses, and being too wide, making all valid arguments circular. (shrink)

An ad hominem fallacy is committed when an individual employs an irrelevant personal attack against an opponent instead of addressing that opponent’s argument. Many discussions of such fallacies discuss judgments of relevance about such personal attacks, and consider how we might distinguish those that are relevant from those that are not. This paper will argue that the literature on bias and testimony can helpfully contribute to that analysis. This will highlight ways in which biases, particularly unconscious biases, can make ad (...) hominem fallacies seem effective, even when the irrelevance is recognized. (shrink)

The Linda paradox is a key topic in current debates on the rationality of human reasoning and its limitations. We present a novel analysis of this paradox, based on the notion of verisimilitude as studied in the philosophy of science. The comparison with an alternative analysis based on probabilistic confirmation suggests how to overcome some problems of our account by introducing an adequately defined notion of verisimilitudinarian confirmation.

Extends the theory of conditional elements in three ways. The critical way, primarily due to the senior author, is the solution to the fallacy of the strengthened antecedent within classical logic.

This essay offers constructive criticism of the book “In Defense of Kant’s Religion” (2008), by Chris L. Firestone and Nathan Jacobs. Follow the link given here to see the published version of this article. In the same journal issue where that version appeared (Faith & Philosophy 29.2), Jacobs and Firestone each published essays that claimed to respond to my criticisms of their book; but for the most part they merely skirted around the points my article makes, often avoiding the key (...) issues (e.g., by imputing alleged "fallacies" to my paper and using these as excuses to avoid discussing the genuine issues), sometimes making claims that were simply false in the process. In Faith and Philosophy 29.3 (July 2012):340-346, I published a general response to the whole debate over their book, without going into the sad details of the tactics they employed. But in a footnote (p.342n) I referred the reader to a detailed, point-by-point rebuttal to their (non-)arguments, as an addendum to that article, that would be uploaded here on my academia. edu site. This version of my original paper uploaded here contains the identical text for the paper itself (i.e., the first 15 pages of the original typescript have not been changed); but I have added an Appendix (starting on p.16) that responds, point-by-point to the Firestone and Jacobs essays. Warning to the faint-hearted: this discussion should not be read by anyone who is considering giving up their study of philosophy on the grounds that philosophers typically waste their time merely talking past each other, because for such a person, reading the Appendix to the version of the paper uploaded here could be the straw that breaks the camel's back! As I wrote it, I found myself sometimes wishing I had not published a promise to provide such material, because it is an embarrassment to philosophy that philosophers sometimes treat each other in the way illustrated by the two essays I am responding to. I only hope that taking the trouble to publish such a detailed response will help some readers recognize how important it is to give one's interlocuter the benefit of the doubt wherever possible (as I have tried to do here, for Firestone and Jacobs--and I would welcome their detailed explanations, if they think I have not done so). In any case, I hope the (unpublished) Appendix, uploaded here, will illustrate the fact that there are more important values to consider, when conducting a philosophical argument, than merely persuading others that "I’m right!". (shrink)

Crupi et al. (2008) offer a confirmation-theoretic, Bayesian account of the conjunction fallacy—an error in reasoning that occurs when subjects judge that Pr( h 1 & h 2 | e ) > Pr( h 1 | e ). They introduce three formal conditions that are satisfied by classical conjunction fallacy cases, and they show that these same conditions imply that h 1 & h 2 is confirmed by e to a greater extent than is h 1 alone. Consequently, they suggest (...) that people are tracking this confirmation relation when they commit conjunction fallacies. I offer three experiments testing the merits of Crupi et al.’s account specifically and confirmation-theoretic accounts of the conjunction fallacy more generally. The results of Experiment 1 show that, although Crupi et al.’s conditions do seem to be causally linked to the conjunction fallacy, they are not necessary for it; there exist cases that do not meet their three conditions in which subjects still tend to commit the fallacy. The results of Experiments 2 and 3 show that Crupi et al.’s conditions, and those offered by other confirmation-theoretic accounts of the fallacy, are not sufficient for the fallacy either; there exist cases that meet all three of CFT’s conditions in which subjects do not tend to commit the fallacy. Additionally, these latter experiments show that such confirmation-theoretic conditions are at best only weakly causally relevant to the presence of the conjunction fallacy. Given these findings, CFT’s account specifically, and any general confirmation-theoretic account more broadly, falls short of offering a satisfying explanation of the presence of the conjunction fallacy. (shrink)

Denying the antecedent is an invalid form of reasoning that is typically identified and frowned upon as a formal fallacy. Contrary to arguments that it does not or at least should not occur, denying the antecedent is a legitimate and effective strategy for undermining a position. Since it is not a valid form of argument, it cannot prove that the position is false. But it can provide inductive evidence that this position is probably false. In this role, it is neither (...) defective nor deceptive. Denying the antecedent provides inductive support for rejecting a claim as improbable. (shrink)

Este libro estudia cuestiones pertenecientes al campo de la lógica aplicada, concretamente de teoría de la argumentación informal. Abarca el análisis de los principales tipos de errores por incom­petencia argumentativa a partir de un enfoque nor­mativo actualizado y con una propuesta de taxono­mía de falacias lógicas informales basada en los cri­terios básicos de buena argumentación. Se identifi­can, describen y ejemplifican, con textos de varios niveles de dificultad, las falacias más habituales (en­tre ellas, las falacias «ad hominem, ad populum, petitio principii», (...) por inducción precipitada, falsa analogía, falso dilema) presentes en diferentes interacciones lin­güísticas interpersonales (documentos políticos, pe­riodísticos, pseudocientíficos, filosóficos) formu­ladas en lenguajes naturales. A lo largo del libro, los principales epígrafes se ilustran con textos extraídos del «Quijote» y de obras de Lewis Carroll. En los capí­tulos iniciales se abordan asuntos previos recomen­dables para la buena comprensión de los capítulos de desarrollo de falacias específicas, a saber, la re­la­ción entre lógica y retórica, los distintos tipos de ar­gumentos, la relación entre razonar y argumentar, el lugar de las emociones en la argumentación falaz y las distintas teorías y definiciones de falacia, así como los errores conceptuales más comunes asociados con el término o el vínculo entre falacias y paradojas. Se re­servan dos capítulos finales, uno sobre falacias bioéticas contemporáneas, y otro con una propuesta de «Código de Buenas Prácticas Argumentativas», fun­damentado en los criterios a partir de los que se ela­bora la taxonomía de falacias del libro. (shrink)