The effect of contextual factors on the judgement of informal reasoning fallacies

Informal reasoning fallacies are arguments that are psychologically persuasive but not valid. In order to judge the validity of these arguments one has to be sensitive to the context in which they appear. However, there is no empirical study that examines students' sensitivity to contextual factors and whether contextual factors actually influence their ability to identify informal reasoning fallacies. We hypothesized that when explicitly presented with different argumentative contexts, students' performance would reflect their sensitivity to the contextual nature of informal reasoning fallacies. The two experiments that we conducted support this hypothesis and emphasize the mediating role of perspective taking in students' ability to identify fallacious arguments.     

The role of text representation in students' ability to identify fallacious arguments

Informal reasoning fallacies are arguments that, though they may seem persuasive, are not valid. The psychological aspect of informal reasoning fallacies, specifically the identification of factors that influence students' ability to identify fallacies, has not been the subject of empirical study. The aim of this study was to test the hypothesis that subjects' ability to identify fallacious arguments is associated with the representation of the argumentative text in the cognitive system. In the first experiment, we tested the hypothesis through a recall task. In the second experiment, we tested the hypothesis through a classification task. The results of the experiments confirm the research hypothesis and point to the role of argumentative structures in argumentation tasks.     

The effect of a reason's truth-value on the judgment of a fallacious argument

Informal reasoning fallacies are arguments that are psychologically persuasive but not valid. In the context of informal reasoning fallacies, the truth-value of the reason in support of a given claim is irrelevant to judging the validity of the argument as a whole. This property stands in sharp contrast with the general role of the reason's truth-value in judging arguments in general. The aim of this study was to test the hypothesis that in the context of informal reasoning fallacies the truth-value of a reason influences pupils' judgment of the extent to which the reason supports the claim. The results of the study confirm the research hypothesis.     

Judging the plausibility of arguments in scientific texts: a student–scientist comparison

The ability to evaluate scientific claims and evidence is an important aspect of scientific literacy and requires various epistemic competences. Readers spontaneously validate presented information against their knowledge and beliefs but differ in their ability to strategically evaluate the soundness of informal arguments. The present research investigated how students of psychology, compared to scientists working in psychology, evaluate informal arguments. Using a think-aloud procedure, we identified the specific strategies students and scientists apply when judging the plausibility of arguments and classifying common argumentation fallacies. Results indicate that students, compared to scientists, have difficulties forming these judgements and base them on intuition and opinion rather than the internal consistency of arguments. Our findings are discussed using the mental model theory framework. Although introductory students validate scientific information against their knowledge and beliefs, their judgements are often erroneous, in part because their use of strategy is immature. Implications for systematic trainings of epistemic competences are discussed.     

The rationality of informal argumentation: a Bayesian approach to reasoning fallacies

Classical informal reasoning "fallacies," for example, begging the question or arguing from ignorance, while ubiquitous in everyday argumentation, have been subject to little systematic investigation in cognitive psychology. In this article it is argued that these "fallacies" provide a rich taxonomy of argument forms that can be differentially strong, dependent on their content. A Bayesian theory of content-dependent argument strength is presented. Possible psychological mechanisms are identified. Experiments are presented investigating whether people's judgments of the strength of 3 fallacies--the argumentum ad ignorantiam, the circular argument or petitio principii, and the slippery slope argument--are affected by the factors a Bayesian account predicts. This research suggests that Bayesian accounts of reasoning can be extended to the more general human activity of argumentation.     

Suppressing valid inferences with conditionals

Three experiments are reported which show that in certain contexts subjects reject instances of the valid modus ponens and modus tollens inference form in conditional arguments. For example, when a conditional premise, such as: If she meets her friend then she will go to a play, is accompanied by a conditional containing an additional requirement: If she has enough money then she will go to a play, subjects reject the inference from the categorical premise: She meets her friend, to the conclusion: She will go to a play. Other contexts suppress the conditional fallacies. The first experiment demonstrates the effects of context on conditional reasoning. The second experiment shows that the inference suppression disappears when the categorical premise refers to both of the antecedents, such as: She meets her friend and she has enough money. In this case, subjects make both the valid inferences and the fallacies, regardless of the contextual information. The third experiment establishes that when subjects are given general information about the duration of a situation in which a conditional inducement was uttered, such as: If you shout then I will shoot you, they reject both the valid inferences and the fallacies. The results suggest that the interpretation of premises plays an even more central role in reasoning than has previously been admitted.     

Defeasible reasoning and informal fallacies

This paper argues that some traditional fallacies should be considered as reasonable arguments when used as part of a properly conducted dialog. It is shown that argumentation schemes, formal dialog models, and profiles of dialog are useful tools for studying properties of defeasible reasoning and fallacies. It is explained how defeasible reasoning of the most common sort can deteriorate into fallacious argumentation in some instances. Conditions are formulated that can be used as normative tools to judge whether a given defeasible argument is fallacious or not. It is shown that three leading violations of proper dialog standards for defeasible reasoning necessary to see how fallacies work are: (a) improper failure to retract a commitment, (b) failure of openness to defeat, and (c) illicit reversal of burden of proof.     

The Vices of Argument

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.     

Fallacies

Fallacies are things people commit, and when they commit them they do something wrong. What kind of activities are people engaged in when they commit fallacies, and in what way are they doing something wrong? Many different things are called fallacies. The diversity of the use of the concept of a fallacy suggests that we are dealing with a family of cases not related by a common essence. However, we suggest a simple account of the nature of fallacies which encompasses them all, viz., the term “fallacy” is our most general term for criticizing any general procedure used for the fixation of beliefs that has an unacceptably high tendency to generate false or unfounded beliefs, relative to that method of fixing beliefs. Very different sorts of things called fallacies are examined in the light of this account, e.g., denying the antecedent, circular arguments, so-called informal fallacies, and propositions said to be fallacies. We do not provide a theory of fallacies. Still, on our account pretty much all of those things that have been called fallacies are fallacies, and they have been called fallacies for pretty much the same reasons.     

Who Reasons Well? Two Studies of Informal Reasoning Among Children of Different Grade,Ability, and Knowledge Levels

This article presents the results of two experiments addressing the relation of reasoning skill to student grade, ability, and knowledge levels. In the first experiment, three levels of students within each of four grades-5, 7, 9, or 1 1-were designated as intellectually gifted, average, or below average. They were given three tasks involving everyday problems for which they provided solutions and justifications. The second experiment included the measurement of domain knowledge with grade and ability level. Measures of informal reasoning showed a substantial relation between ability level and performance, with knowledge significantly related to performance measures, such as number and type of reasons generated, but not to measures involving soundness or acceptability of arguments, which were explained by ability level. Grade was related only to an increase in personal and broadly defined social reasons; other effects were "washed out" by knowledge. The findings were interpreted in terms of a two-component model of informal reasoning, a knowledgeexperiential component and an informal reasoning skill component based on the acquisition of argumentation-based language structures termed conventions of reasoning. Consideration of the relation of reasoning to learning and to instruction emphasized the importance of teaching informal reasoning skill.     

Emerging Infectious Diseases: Coping with Uncertainty

The world’s scientific community must be in a state of constant readiness to address the threat posed by newly emerging infectious diseases. Whether the disease in question is SARS in humans or BSE in animals, scientists must be able to put into action various disease containment measures when everything from the causative pathogen to route(s) of transmission is essentially uncertain. A robust epistemic framework, which will inform decision-making, is required under such conditions of uncertainty. I will argue that this framework should have reasoning at its center and, specifically, that forms of reasoning beyond deduction and induction should be countenanced by scientists who are confronted with emerging infectious diseases. In previous articles, I have presented a case for treating certain so-called traditional informal fallacies as rationally acceptable forms of argument that can facilitate scientific inquiry when little is known about an emerging disease. In this article, I want to extend that analysis by highlighting the unique features of these arguments that makes them specially adapted to cope with conditions of uncertainty. Of course, such a view of the informal fallacies must at least be consistent with the reasoning practices of scientists, and particularly those scientists (viz. epidemiologists) whose task it is to track and respond to newly emerging infectious diseases. To this end, I draw upon examples of scientific reasoning from the UK’s BSE crisis, a crisis that posed a significant threat to both human and animal health.

Associations between myside bias on an informal reasoning task and amount of post‐secondary education

One hundred and twelve undergraduate university students completed an informal reasoning task in which they were asked to generate arguments both for and against the position they endorsed on three separate issues. Performance on this task was evaluated by comparing the number of arguments they generated which endorsed (myside arguments) and which refuted (otherside arguments) their own position on that issue. Participants generated more myside arguments than otherside arguments on all three issues, thus consistently showing a myside bias effect on each issue. Differences in cognitive ability were not associated with individual differences in myside bias. However, year in university was a significant predictor of myside bias. The degree of myside bias decreased systematically with year in university. Year in university remained a significant predictor of myside bias even when both cognitive ability and age were statistically partialled out. Copyright © 2003 John Wiley & Sons, Ltd.     

Being unreasonable: Perelman and the problem of fallacies

Most work on fallacies continues to conceptualize fallacious reasoning as involving a breach of a formal or quasi-formal rule. Chaim Perelman's theory of argumentation provides a way to conceptualize fallacies in a completely different way. His approach depends on an understanding of standards of rationality as essentially connected with conceptions of universality. Such an approach allows one to get beyond some of the basic problems of fallacy theory, and turns informal logic toward substantive philosophical questions. I show this by reinterpreting three so-called fallacies - theargumentum ad baculum, equivocation and composition/division - in the light of Perelman's account.     

Contextual judgments of quality of life and adolescent cognitive development

This research explored the relationship between adolescents' level of cognitive reasoning and their contextual judgments of the factors affecting quality of life. In comparison to adolescents at relatively lower levels of cognitive development, it was predicted that those who have achieved higher levels of cognitive reasoning would be: (1) more likely to identify social and interpersonal aspects of life as factors related to quality of life and (2) less likely to identify self issues. Subjects were 443 tenth-grade students from four Michigan school districts. The students were administered the Reasoning Level Test (RLT) and also asked to identify the aspects of their lives that they felt were the most and least satisfying at the moment. A median split was performed and each student was assigned to either a high or low cognitive-level group based upon his/her RLT score. The findings supported the above predictions, but more so in regard to negative than positive factors. The findings are also in line with cognitive-developmental theories of adolescence and indicate that cognitive structures and the specific nature of the factors perceived to influence one's life may mediate contextual judgments of these factors.     

The macrostructure of informal arguments: A proposed model and analysis

Theories of informal reasoning and critical thinking often maintain that everyday, informal arguments can be classified into types based on the specific organization that the premises or reasons enter into in their support for the conclusion (Snoeck Henkemans, 2000; Vorobej, 1995b). Three general types are identified: convergent, coordinately linked, and subordinately linked arguments. There has been no empirical research, however, to determine whether these structural distinctions have any psychological reality. In the first two of four experiments, college students were presented with premise pairs from larger, informal arguments and were asked to judge the nature of the relationship between the premises in a pair. The judgments involved applying “tests” of linkage, subordination, and so on, that have been proposed in the theoretical literature on argument analysis (e.g., Walton, 1996a; Yanal, 1991). Results suggest that adults can effectively distinguish between linked (interdependent) and convergent relationships and can further distinguish between interdependencies that are full and those that are merely partial. Adults also distinguished between subordinate and nonsubordinate relations. Experiments 3 and 4 provide evidence that adults make use of information about argument structure in evaluating argument strength and in categorizing arguments. Experiment 4 further suggests that facility with macrostructure is only modestly related to deductive reasoning competence. Findings are framed in terms of a speculative account of how argument structure is identified and mentally represented.     

Deductivism and the Informal Fallacies

This essay proposes and defends a general thesis concerning the nature of fallacies of reasoning. These in distinctive ways are all said to be deductively invalid. More importantly, the most accurate, complete and charitable reconstructions of these species and specimens of the informal fallacies are instructive with respect to the individual character of each distinct informal fallacy. Reconstructions of the fallacies as deductive invalidities are possible in every case, if deductivism is true, which means that in every case they should be formalizable in an expressively comprehensive formal symbolic deductive logic. The general thesis is illustrated by a detailed examination of Walter Burleigh's paradox in his c. 1323 work, De Puritate Artis Logicae Tractatus Longior (Longer Treatise on the Purity of Logic), as a challenge to the deductive validity of hypothetical syllogism. The paradox has the form, ‹If I call you a swine, then I call you an animal; if I call you an animal, then I speak truly; therefore, if I call you a swine, then I speak truly'. Several solutions to the problem are considered, and the inference is exposed as an instance of the common deductive fallacy of equivocation.     

Giving Science a Bad Name: Politically and Commercially Motivated Fallacies in BSE Inquiry

It is a feature of scientific inquiry that it proceeds alongside a multitude of non-scientific interests. This statement is as true of the scientific inquiries of previous centuries, many of which brought scientists into conflict with institutionalised religious thinking, as it is true of the scientific inquiries of today, which are conducted increasingly within commercial and political contexts. However, while the fact of the coexistence of scientific and non-scientific interests has changed little over time, what has changed with time is the effect of this coexistence on scientific inquiry itself. While scientists may no longer construct their theories with various religious dictates in mind, growing commercial and political interests in science have served to distort the interpretation of science. Using the U.K.’s recent crisis with bovine spongiform encephalopathy (BSE) as my context, I examine two ways in which this distortion has occurred – the interpretation of the science of BSE by politicians and by commercial parties for the purposes of justifying policy decisions and informing the public of risk, respectively. Fallacious reasoning, I contend, is the manifestation of this distortion in these contexts. In demonstration of this claim, I examine how politicians and commercial parties alike have employed two fallacies in their assessments of the science of BSE. These fallacies extend in novel ways the set of so-called traditional informal fallacies. The interpretation of science, I conclude, is a rich context in which to conduct a study of fallacious reasoning; moreover, such a study can contribute in significant ways, I argue, to the public understanding of science.     

Burden of proof

This paper presents an analysis of the concept of burden of proof in argument. Relationship of burden of proof to three traditional informal fallacies is considered: (i) argumentum ad hominem, (ii) petitio principii, and (iii) argumentum ad ignorantiam. Other topics discussed include persuasive dialoque, pragmatic reasoning, legal burden of proof, plausible reasoning in regulated disputes, rules of dialogue, and the value of reasoned dialogue.     

Domain-specific identity, epistemic regulation, and intellectual ability as predictors of belief-biased reasoning: a dual-process perspective

To explore the hypothesis that domain-specific identity development predicts reasoning biases, adolescents and young adults completed measures of domain-general and domain-specific identity, epistemic regulation, and intellectual ability and evaluated arguments that either supported or threatened their occupational goals. Biases were defined as the use of sophisticated reasoning to reject goal-threatening arguments and the use of cursory reasoning to accept goal-supportive arguments. Across two measures of bias, hierarchical regression analyses showed that domain-specific vocational identity and epistemic regulation best predicted reasoning biases. Neither age nor intellectual ability predicted significant variance in biases after vocational identity and epistemic regulation scores were entered into the regression equations. The results support the thesis that biases in specific domains can be explained both by domain-specific personality attributes and by domain-general metacognitive dispositions to monitor reasoning and decontextualize problem structure from superficial contents. A dual-process framework is proposed to explain the relationships among identity, epistemic regulation, age, intellectual ability, and reasoning biases.     

Who is susceptible to conjunction fallacies in category-based induction?

Recent evidence suggests that the conjunction fallacy observed in people’s probabilistic reasoning is also to be found in their evaluations of inductive argument strength. We presented 130 participants with materials likely to produce a conjunction fallacy either by virtue of a shared categorical or a causal relationship between the categories in the argument. We also took a measure of participants’ cognitive ability. We observed conjunction fallacies overall with both sets of materials but found an association with ability for the categorical materials only. Our results have implications for accounts of individual differences in reasoning, for the relevance theory of induction, and for the recent claim that causal knowledge is important in inductive reasoning.