Hempel’s Provisos and <Emphasis Type="Italic">Ceteris Paribus</Emphasis> Clauses

The problem of ceteris paribus clauses and Hempel’s problem of provisos are closely-related difficulties. Both challenge advocates of accounts of scientific theories involving laws understood as universal generalizations, and they have been treated as identical problems. Earman and Roberts argue that the problems are distinct. Towards arguing against them, I characterize the relationship between Hempel’s provisos and one way of expressing ceteris paribus clauses. I then describe the relationship between the problems attributed to the clauses, suggesting that they form a single problem-cluster. However, Hempel’s way of formulating provisos and discussing what they involve entangles provisos with the problem of skepticism. This creates a departure in Hempel’s discussion of provisos from the distinctive problem of vacuity which characterizes the problem of ceteris paribus clauses, though for different reasons than Earman and Roberts suggest.     

Familiarity can increase stereotyping

Two experiments show that repeated exposure to information about a target person reduces individuation and thereby increases stereotyping of the target person based on social group memberships. The effect is not due to familiarity-induced liking (the mere exposure effect), nor is it mediated by increased accessibility of the target’s social category, nor by increases in perceived social judgeability. The results are most consistent with the use of feelings of familiarity as a regulator of processing mode, such that familiar objects receive less systematic or analytic processing. In everyday life, frequent exposure to another person ordinarily produces not only familiarity but also liking, individuated knowledge, and friendship, factors that may effectively limit stereotyping. But when previous exposure is unconfounded from these other factors, its effect can be to increase stereotyping.     

Virtual Reality Exposure Therapy for PTSD symptoms after a road accident: an uncontrolled case series

This report examined whether Virtual Reality Exposure Therapy (VRET) could be used in the treatment of posttraumatic stress disorder (PTSD) symptoms in the aftermath of a serious motor vehicle accident. Six individuals reporting either full or severe subsyndromal PTSD completed 10 sessions of VRET, which was conducted using software designed to create real-time driving scenarios. Results indicated significant reductions in posttrauma symptoms involving reexperiencing, avoidance, and emotional numbing, with effect sizes ranging from d=.79 to d=1.49. Indices of clinically significant and reliable change suggested that the magnitude of these changes was meaningful. Additionally, high levels of perceived reality ("presence") within the virtual driving situation were reported, and patients reported satisfaction with treatment. Results are discussed in light of the possibility for VRET to be useful in guiding exposure in the treatment of PTSD following road accidents.     

Can emotions be truly group level? Evidence regarding four conceptual criteria

Recent advances in understanding prejudice and intergroup behavior have made clear that emotions help explain people's reactions to social groups and their members. Intergroup emotions theory (D. M. Mackie, T. Devos, & E. R. Smith, 2000; E. R. Smith, 1993) holds that intergroup emotions are experienced by individuals when they identify with a social group, making the group part of the psychological self. What differentiates such group-level emotions from emotions that occur purely at the individual level? The authors argue that 4 key criteria define group-level emotions: Group emotions are distinct from the same person's individual-level emotions, depend on the person's degree of group identification, are socially shared within a group, and contribute to regulating intragroup and intergroup attitudes and behavior. Evidence from 2 studies supports all 4 of these predictions and thus points to the meaningfulness, coherence, and functionality of group-level emotions.     

Visualization,pattern recognition,and forward search: effects of playing speed and sight of the position on grandmaster chess errors

A new approach examined two aspects of chess skill, long a popular topic in cognitive science. A powerful computer‐chess program calculated the number and magnitude of blunders made by the same 23 grandmasters in hundreds of serious games of slow (“classical”) chess, regular “rapid” chess, and rapid “blindfold” chess, in which opponents transmit moves without ever seeing the actual position. Rapid chess led to substantially more and larger blunders than classical chess. Perhaps more surprisingly, the frequency and magnitude of blunders did not differ in rapid versus blindfold play, despite the additional memory and visualization load imposed by the latter. We discuss the involvement of various cognitive processes in human problem‐solving and expertise, especially with respect to chess. Prior opposing views about the basis of general chess skill have emphasized the dominance of either (a) swift pattern recognition or (b) analyzing ahead, but both seem important and the controversy appears currently unresolvable and perhaps fruitless.     

A note on the analysis of designs in which subjects receive each stimulus only once

In social psychological experiments, the manipulations of interest are often presented to subjects along with, or as part of, some stimulus. An example would be a manipulation of the verbal label associated with a stimulus photograph, in a person perception study. Ordinarily it is not possible for stimuli to be completely crossed with treatments because subjects cannot be exposed to any stimulus more than once. In such designs it is wise to counterbalance the assignment of stimuli to treatment conditions, but this gives rise to difficulties in the analysis of the experimental data. Data from such designs have frequently been misanalyzed in the published literature. This paper presents a method of constructing a counter-balancing scheme to simplify the analysis, and appropriate methods of analysis for both the simplified and the general case. It is emphasized that stimuli are generally best treated as a random factor in such designs, permitting increased generalizability, but the case where the stimulus factor is fixed is also considered.     

Dewey Between the Lines: George Kelly and the Pragmatist Tradition

In his own somewhat sly and sardonic way, George Kelly always insisted that personal construct theory could not be assimilated into any other kind of psychology. We believe this was not an example of Kelly being difficult or protecting his turf, but that he resisted such efforts at categorization because he formulated personal construct psychology from an entirely different set of assumptions than those which have traditionally guided the construction of psychological theories. We begin by looking at the unusual life path Kelly took in order to enter the field of psychology and what it reveals about the independent turn of mind he brought to creating his own theory of personality. We then examine what we believe is the single most important influence on Kelly's thinking—the tradition of American pragmatism, in general, and the philosophy and psychology of John Dewey, in particular. We argue that Kelly embraced the pragmatic epistemological assumptions that guided Dewey's work, and that he used these assumptions to develop the only pragmatic theory of personality and psychotherapy. It is, in fact, the influence of Dewey and the pragmatists that makes personal construct psychology so different from and, at times, more difficult to understand than other, more traditional, “realist” theories, but it is also this pragmatic orientation that makes Kelly's theory such an important contribution.     

Domain-specific conflict adaptation without feature repetitions

An influential account of how cognitive control deals with conflicting sources of information holds that conflict is monitored by a module that automatically recruits attention to resolve the conflict. This leads to reduced effects of conflict on the subsequent trial, a phenomenon termed conflict adaptation. A prominent question is whether control processes are domain specific—that is, recruited only by the particular type of conflict they resolve. Previous studies that have examined this question used two-choice tasks in which feature repetition effects could be responsible for domain-specific adaptation effects. We report two experiments using four-choice (Experiment 1) and five-choice (Experiment 2) tasks that contain two types of irrelevant sources of potentially conflicting information: stimulus location (Simon conflict) and distractors (flanker conflict). In both experiments, we found within-type conflict adaptation for both types of conflict after eliminating trials on which stimulus features were repeated from one trial to the next. Across-type conflict adaptation, however, was not significant. Thus, conflict adaptation was due to domain-specific recruitment of cognitive control. Our results add converging evidence to the idea that multiple independent control processes are involved in reactive cognitive control, although whether control is always local remains to be determined.