Natural, unnatural, and supernatural concepts

Five experiments investigating information-processing consequences of concept naturalness and unnaturalness are reported. In particular, an attempt is made to examine the separate and joint effects of simplicity and entrenchment upon reasoning with natural and unnatural concepts. The experiments employed four variants of a concept-selection task in which subjects characterized the state of an object at some future time on the basis of information about the object at that time and at some earlier time. In all five experiments, both simplicity and entrenchment affected ease of information processing. The last two experiments showed that the effect of simplicity was greater than that of entrenchment. An informationprocessing model of task performance provided a very good account of the latency and error data. Scores from the concept-selection task correlated with scores from a set of psychometric inductive-reasoning tests; indeed, the correlations were higher than those usually found between cognitive task performance and psychometrically measured intelligence. Processing of nonentrenched concepts may provide a useful means for studying the nature of intelligent performance.     

Contraction: On the Decision-Theoretical Origins of Minimal Change and Entrenchment

We present a decision-theoretically motivated notion of contraction which, we claim, encodes the principles of minimal change and entrenchment. Contraction is seen as an operation whose goal is to minimize loses of informational value. The operation is also compatible with the principle that in contracting A one should preserve the sentences better entrenched than A (when the belief set contains A). Even when the principle of minimal change and the latter motivation for entrenchment figure prominently among the basic intuitions in the works of, among others, Quine and Ullian (1978), Levi (1980, 1991), Harman (1988) and Gärdenfors (1988), formal accounts of belief change (AGM, KM – see Gärdenfors (1988); Katsuno and Mendelzon (1991)) have abandoned both principles (see Rott (2000)). We argue for the principles and we show how to construct a contraction operation, which obeys both. An axiom system is proposed. We also prove that the decision-theoretic notion of contraction can be completely characterized in terms of the given axioms. Proving this type of completeness result is a well-known open problem in the field, whose solution requires employing both decision-theoretical techniques and logical methods recently used in belief change.     

Belief Change as Propositional Update

This study examines the problem of belief revision, defined as deciding which of several initially accepted sentences to disbelieve, when new information presents a logical inconsistency with the initial set. In the first three experiments, the initial sentence set included a conditional sentence, a non-conditional (ground) sentence, and an inferred conclusion drawn from the first two. The new information contradicted the inferred conclusion. Results indicated that conditional sentences were more readily abandoned than ground sentences, even when either choice would lead to a consistent belief state, and that this preference was more pronounced when problems used natural language cover stories rather than symbols. The pattern of belief revision choices differed depending on whether the contradicted conclusion from the initial belief set had been a modus ponens or modus tollens inference. Two additional experiments examined alternative model-theoretic definitions of minimal change to a belief state, using problems that contained multiple models of the initial belief state and of the new information that provided the contradiction. The results indicated that people did not follow any of four formal definitions of minimal change on these problems. The new information and the contradiction it offered was not, for example, used to select a particular model of the initial belief state as a way of reconciling the contradiction. The preferred revision was to retain only those initial sentences that had the same, unambiguous truth value within and across both the initial and new information sets. The study and results are presented in the context of certain logic-based formalizations of belief revision, syntactic and model-theoretic representations of belief states, and performance models of human deduction. Principles by which some types of sentences might be more “entrenched” than others in the face of contradiction are also discussed from the perspective of induction and theory revision.     

Basic Entrenchment

In contrast to other prominent models of belief change, models based on epistemic entrenchment have up to now been applicable only in the context of very strong packages of requirements for belief revision. This paper decomposes the axiomatization of entrenchment into independent modules. Among other things it is shown how belief revision satisfying only the ‘basic’ postulates of Alchourrón, Gärdenfors and Makinson can be represented in terms of entrenchment.     

Comparative Possibility in Set Contraction

In a recent article, Zhang and Foo generalized the AGM postulates for contraction to include infinite epistemic input. The new type of belief change is called set contraction. Zhang and Foo also introduced a constructive model for set contraction, called nicely ordered partition, as a generalization of epistemic entrenchment. It was shown however that the functions induced from nicely ordered partitions do not quite match the postulates for set contraction. The mismatch was fixed with the introduction of an extra condition called the limit postulate. The limit postulate establishes a connection between contraction by infinite epistemic input and contraction by finite epistemic input (reducing the former to the latter) and it is appealing both on mathematical and on conceptual grounds. It is debatable however whether the limit postulate can be adopted as a general feature of rationality in set contraction. Instead we propose that the limit postulate is viewed as a condition characterizing an important special case of set contraction functions. With this reading in mind, in this article we introduce an alternative generalization of epistemic entrenchment, based on the notion of comparative possibility. We prove that the functions induced from comparative possibility preorders precisely match those satisfying the postulates for set contraction (without the limit postulate). The relationship between comparative possibility and epistemic entrenchment is also investigated. Finally, we formulate necessary and sufficient conditions under which the functions induced from comparative possibility preorders coincide with the special class of contraction functions characterized by the limit postulate.     

Iterated belief change based on epistemic entrenchment

In this paper it is argued that, in order to solve the problem of iterated belief change, both the belief state and its input should be represented as epistemic entrenchment (EE) relations. A belief revision operation is constructed that updates a given EE relation to a new one in light of an evidential EE relation. It is shown that the operation in question satisfies generalized versions of the Gärdenfors revision postulates. The account offered is motivated by Spohn's ordinal conditionalization functions, and can be seen as the Jeffrization of a proposal considered by Rott.I am indebted John G. Bennett and Henry E. Kyburg. jr. for their insightful comments on an earlier draft of this paper. I thank the referees forErkenntnis who, apart from giving extended comments and suggestions, provided me with some hard-to-find relevant material. I also thank Prashanta Bandyopadhyay, Norman Foo, Maurice Pagnucco, Hans Rott and Mary-Anne Williams for their suggestions. The errors that remain are, of course, mine.     

Counter-argument self-efficacy predicts choice of belief-defense strategies

Research has identified many strategies people use to defend against belief-inconsistent information. However, little research has identified factors that predict which defense strategy people will use when more than one is available. Two experiments tested whether people choose to counter-argue belief-inconsistent information because they believe arguing will be successful, but resort to weaker defense strategies because they believe arguing will be unsuccessful. Exposure to strong versus weak belief-inconsistent information caused a decrease in counter-arguing and an increase in ignoring (Experiment 1) or claiming a belief to be a matter of opinion (untestable) rather than a matter of fact (testable; Experiment 2). Consistent with self-efficacy theory, expectations of successful counter-arguing was the mechanism responsible for both effects. When people feel less capable of successfully counter-arguing because the information is too difficult to refute, they resort to epistemically weaker defense strategies in order to preserve their belief.     

The Consistency Argument for Ranking Functions

The paper provides an argument for the thesis that an agent’s degrees of disbelief should obey the ranking calculus. This Consistency Argument is based on the Consistency Theorem. The latter says that an agent’s belief set is and will always be consistent and deductively closed iff her degrees of entrenchment satisfy the ranking axioms and are updated according to the ranktheoretic update rules. Special Issue Formal Epistemology I. Edited by Branden Fitelson     

Systematic Withdrawal

Although AGM theory contraction (Alchourrón et al., 1985; Alchourrón and Makinson, 1985) occupies a central position in the literature on belief change, there is one aspect about it that has created a fair amount of controversy. It involves the inclusion of the postulate known as Recovery. As a result, a number of alternatives to AGM theory contraction have been proposed that do not always satisfy the Recovery postulate (Levi, 1991, 1998; Hansson and Olsson, 1995; Fermé, 1998; Fermé and Rodriguez, 1998; Rott and Pagnucco, 1999). In this paper we present a new addition, systematic withdrawal, to the family of withdrawal operations, as they have become known. We define systematic withdrawal semantically, in terms of a set of preorders, and show that it can be characterised by a set of postulates. In a comparison of withdrawal operations we show that AGM contraction, systematic withdrawal and the severe withdrawal of Rott and Pagnucco (1999) are intimately connected by virtue of their definition in terms of sets of preorders. In a future paper it will be shown that this connection can be extended to include the epistemic entrenchment orderings of Gärdenfors (1988) and Gärdenfors and Makinson (1988) and the refined entrenchment orderings of Meyer et al. (2000).     

PERSONAL ATTACHMENT TO BELIEFS

Abstract: There is a tendency in philosophical discussions to see beliefs as belonging to specific people—to see things in terms of “your” belief, or “my” belief, or “Smith's” belief. I call this “personal attachment to beliefs.” This mindset is unconscious, deeply ingrained, and a powerful background stance in discussion and thinking. Attachment has a negative impact on the quality of philosophical discussion and learning: difficulties in acknowledging error and changing beliefs, blindness to new evidence, difficulties in understanding new ideas, entrenchment in views, rancorous behavior, and the encouragement of competitive personal contests rather than collaborative searches for the truth. This article investigates the nature of attachment and traces out some of the undesirable consequences for classroom philosophical discussion, thinking, writing, and learning. It presents an alternative model to attachment and offers constructive suggestions for implementing the results of the investigation in the philosophy classroom and elsewhere.     

Yes,no, maybe so: a veritistic approach to echo chambers using a trichotomous belief model

I approach the study of echo chambers from the perspective of veritistic social epistemology. A trichotomous belief model is developed featuring a mechanism by which agents will have a tendency to form agreement in the community. The model is implemented as an agent-based model in NetLogo and then used to investigate a social practice called Impartiality, which is a plausible means for resisting or dismantling echo chambers. The implementation exposes additional factors that need close consideration in an evaluation of Impartiality. In particular, resisting or dismantling echo chambers requires the selection of sufficiently low levels of doxastic entrenchment, but this comes with other tradeoffs.     

Experimenter effects on children's understanding of false drawings and false beliefs

Two experiments were conducted in which a variant of J. McGarrigle and M. Donaldson's (1975) "Naughty Teddy" intervention was applied to children's understanding of false drawings and false beliefs. The results showed that preschool children's understanding of the contents of an out-of-date drawing improved when the drawing was made by a capricious agent ("Naughty Snakey" glove puppet) rather than by the experimenter. The children's performance on a false belief task also improved when the events that set up the false belief were the result of the actions of the glove puppet. The results are discussed in terms of the role of children's sensitivity to the pragmatics of interactions in their development of a theory of mind.     

Choosing and refusing: doxastic voluntarism and folk psychology

A standard view in contemporary philosophy is that belief is involuntary, either as a matter of conceptual necessity or as a contingent fact of human psychology. We present seven experiments on patterns in ordinary folk-psychological judgments about belief. The results provide strong evidence that voluntary belief is conceptually possible and, granted minimal charitable assumptions about folk-psychological competence, provide some evidence that voluntary belief is psychologically possible. We also consider two hypotheses in an attempt to understand why many philosophers have been tempted to view belief as involuntary: that belief is a prototype concept and that belief is a dual character concept. Altogether, our findings contribute to longstanding philosophical debates about the relationship between the will and the intellect, while also advancing scientific understanding of important social judgments.     

Retraction and testimonial justification: a new problem for the assurance view

The Assurance View, as advanced by Angus Ross and Richard Moran, makes the epistemology of testimony a matter of interpersonal commitments and entitlements. More specifically, I argue, their position is best understood as claiming that for someone’s belief to be testimonially justified is for some speaker to bear illocutionary responsibility for its truth (while background conditions are met). With this understanding in hand, I present a problem for the view that has so far escaped attention, a problem deriving from the wide freedom we have to retract our assertions. Retraction dissolves the illocutionary responsibilities that were set up by preceding speech acts; but in some circumstances the epistemic significance of a retraction is effectively nil. We can therefore construct cases in which the responsibilities undertaken in testimony have been canceled, while the justification for belief based on it remains in place—and that shouldn’t be possible, if the Assurance View has things right. I present one such case and press its implications.

     

Severe Withdrawal (and Recovery)

The problem of how to remove information from an agent's stock of beliefs is of paramount concern in the belief change literature. An inquiring agent may remove beliefs for a variety of reasons: a belief may be called into doubt or the agent may simply wish to entertain other possibilities. In the prominent AGM framework for belief change, upon which the work here is based, one of the three central operations, contraction, addresses this concern (the other two deal with the incorporation of new information). Makinson has generalised this work by introducing the notion of a withdrawal operation. Underlying the account proffered by AGM is the idea of rational belief change. A belief change operation should be guided by certain principles or integrity constraints in order to characterise change by a rational agent. One of the most noted principles within the context of AGM is the Principle of Informational Economy. However, adoption of this principle in its purest form has been rejected by AGM leading to a more relaxed interpretation. In this paper, we argue that this weakening of the Principle of Informational Economy suggests that it is only one of a number of principles which should be taken into account. Furthermore, this weakening points toward a Principle of Indifference. This motivates the introduction of a belief removal operation that we call severe withdrawal. We provide rationality postulates for severe withdrawal and explore its relationship with AGM contraction. Moreover, we furnish possible worlds and epistemic entrenchment semantics for severe withdrawals.     

Prior belief and polarity in multicue learning.

We report two experiments in which participants are trained using a multicue probability learning (MCPL) task, which attempts to simulate the acquisition of expert judgement by experience in the real world. Participants were asked to predict performance in certain occupations given a profile of personality test results with trial-by-trial outcome feedback. Only some cues were relevant, and the polarity of the cues (positive or negative predictors) was unspecified. In addition, 25% of random noise was added to the feedback to simulate real world uncertainty. The main factor of interest was that the role of prior belief (determined in a separate study of stereotypes) interfered with the learning process. Experiment 1 failed to find any influence of prior belief in the cues that were irrelevant to the criterion being trained. However, in Experiment 2 people learned to use the relevant cues better when their effect conformed with rather than conflicted with prior belief Both experiments showed strong effects of cue polarity, with positive predictors much more easily learned. The results are discussed with reference to the cognitive processes involved in MCPL and closely related tasks.     

How language relates to belief,desire, and emotion understanding

Two experiments examined syntax and semantics as correlates of theory-of-mind (ToM). In Experiment 1 children’s language was examined at 3 years of age in relation to ToM at 3, 3.5, 4, and 5.5 years. Semantics predicted unique variance in later belief understanding but not desire understanding. Syntax did not explain unique variance in belief or desire. In Experiment 2 two measures of syntax and a measure of semantics were used with 65 3–5-year-olds. The syntax measures tested children’s understanding of word order and embedded clauses. They were related to false belief, but contrary to some predictions, were also related to emotion recognition. Performance on language control tasks with low syntactic demands correlated equally well with false belief. In both experiments performance on the syntax and semantics tasks was highly inter-correlated. We argue that ToM is related to general language ability rather than syntax or semantics per se.     

Publication bias and the failure of replication in experimental psychology

Replication of empirical findings plays a fundamental role in science. Among experimental psychologists, successful replication enhances belief in a finding, while a failure to replicate is often interpreted to mean that one of the experiments is flawed. This view is wrong. Because experimental psychology uses statistics, empirical findings should appear with predictable probabilities. In a misguided effort to demonstrate successful replication of empirical findings and avoid failures to replicate, experimental psychologists sometimes report too many positive results. Rather than strengthen confidence in an effect, too much successful replication actually indicates publication bias, which invalidates entire sets of experimental findings. Researchers cannot judge the validity of a set of biased experiments because the experiment set may consist entirely of type I errors. This article shows how an investigation of the effect sizes from reported experiments can test for publication bias by looking for too much successful replication. Simulated experiments demonstrate that the publication bias test is able to discriminate biased experiment sets from unbiased experiment sets, but it is conservative about reporting bias. The test is then applied to several studies of prominent phenomena that highlight how publication bias contaminates some findings in experimental psychology. Additional simulated experiments demonstrate that using Bayesian methods of data analysis can reduce (and in some cases, eliminate) the occurrence of publication bias. Such methods should be part of a systematic process to remove publication bias from experimental psychology and reinstate the important role of replication as a final arbiter of scientific findings.     

Two Egocentric Sources of the Decision to Vote: The Voter's Illusion and the Belief in Personal Relevance

The decision to vote in a national election requires a choice between serving a social good and satisfying one's self-interest. Viewed as a cooperative response in a social dilemma, casting a vote seems irrational because it cannot have a discernible effect on the electoral outcome. The findings of two studies with undergraduate samples suggest that some people vote not because they set aside self-interest, but because they expect their own behaviors to matter. Two psychological processes contribute to this belief: the voter's illusion (the projection of one's own choice between voting and abstention to supporters of the same party or candidate), and the belief in personal relevance (the belief that one's own vote matters regardless of its predictive value for the behavior of others). The rationality of these two egocentric mechanisms depends on the normative framework invoked. Their relevance for actual voting behavior is indicated by their ability to account for four types of variation in turnout rates.     

Scientific faith: Belief in science increases in the face of stress and existential anxiety

Growing evidence indicates that religious belief helps individuals to cope with stress and anxiety. But is this effect specific to supernatural beliefs, or is it a more general function of belief — including belief in science? We developed a measure of belief in science and conducted two experiments in which we manipulated stress and existential anxiety. In Experiment 1, we assessed rowers about to compete (high-stress condition) and rowers at a training session (low-stress condition). As predicted, rowers in the high-stress group reported greater belief in science. In Experiment 2, participants primed with mortality (vs. participants in a control condition) reported greater belief in science. In both experiments, belief in science was negatively correlated with religiosity. Thus, some secular individuals may use science as a form of “faith” that helps them to deal with stressful and anxiety-provoking situations.