Deductive rationality in validating and testing conditional inferences

We asked people to validate conditional inferences (e.g., "A, therefore C" with "if A then C"). People are more likely to look for falsifications ("A and not-C") versus confirmations ("A and C") given a forced choice. Second, falsification rates are lower for logically valid versus invalid inferences. Logically valid inferences are inferences that follow necessarily. Experiment 1 (N = 96) shows that emphasising this logicality constraint increases falsification rates in the validation task and corroborates that validation-by-falsification increases logically correct inference evaluations. Experiment 2 (N = 41) corroborates the other way round that people who are more likely to make logically correct evaluations, show higher falsification performance in the validation task. The results support mental-models theory and suggest alternative theories similarly need to specify how people would go about looking for counterexamples. We proffer such a specification for two alternatives to the model theory. (PsycINFO Database Record (c) 2008 APA, all rights reserved).     

Deductive reasoning and creativity: a cross-cultural study

The present cross-cultural study examined the relationship between deductive reasoning and creativity among college students (M age=20.4 yr., SD= .6) from Hong Kong (n=39) and the United States (n=38). Participants performed tasks designed to measure deductive reasoning, creative writing, and insight problem-solving, all in verbal form. No correlation was found between the performance for deductive reasoning and creativity as measured by creative writing. Insight problem-solving performance correlated significantly with that for both reasoning and creativity. Significant cultural differences favoring the American participants were only found on the creative writing and insight problem-solving tasks, both of which supposedly involve creative thinking. There seems to be cultural dependence for creativity but not for deductive reasoning which suggests a qualification of a strong cultural-relevance view positing pervasive cultural influences on human thinking processes.     

Deductive and inductive conditional inferences: Two modes of reasoning

A number of single- and dual-process theories provide competing explanations as to how reasoners evaluate conditional arguments. Some of these theories are typically linked to different instructions—namely deductive and inductive instructions. To assess whether responses under both instructions can be explained by a single process, or if they reflect two modes of conditional reasoning, we re-analysed four experiments that used both deductive and inductive instructions for conditional inference tasks. Our re-analysis provided evidence consistent with a single process. In two new experiments we established a double dissociation of deductive and inductive instructions when validity and plausibility of conditional problems were pitted against each other. This indicates that at least two processes contribute to conditional reasoning. We conclude that single-process theories of conditional reasoning cannot explain the observed results. Theories that postulate at least two processes are needed to account for our findings.     

Collective rationality in interactive decisions: evidence for team reasoning

Decision theory and game theory rest on a fundamental assumption that players seek to maximize their individual utilities, but in some interactive decisions it seems intuitively reasonable to aim to maximize the utility of the group of players as a whole. Such team reasoning requires collective preferences and a distinctive mode of reasoning from preferences to decisions. Findings from two experiments provide evidence for collective preferences and team reasoning. In lifelike vignettes (Experiment 1) and abstract games (Experiment 2) with certain structural properties, most players preferred team-reasoning strategies to strategies supporting unique Nash equilibria, although individually rational players should choose equilibrium strategies. These findings suggest that team reasoning predicts strategy choices more powerfully than orthodox game theory in some games.     

Deductive reasoning and matching-bias inhibition training: Evidence from a debiasing paradigm

Using the matching bias example, the aim of the present studies was to show that adults' reasoning biases are due to faulty executive inhibition programming. In the first study, the subjects were trained on Wason's classical card selection task; half were given training in how to inhibit the perceptual matching bias (experimental group) and half in logic without the inhibition component (control group). On the pre- and post-tests, their performance was assessed on the Evans conditional rule falsification task (with a negation in the antecedent of the rule), a task that also involves matching bias. In addition, subjects were tested for perceptual field dependence/independence using the Embedded Figures Test. The results brought out a specific inhibition training effect, as well as a clear-cut relationship in the experimental group between receptiveness to training and perceptual field independence. In the second study, the training paradigm was the same except that on the pre- and post-tests, the negation was in the consequent of the conditional rule (in this case, the perceptual matching response corresponds to the logical response). The subjects succeeded on the pre-test, and the matching-bias inhibition training had a negative effect on post-test performance. This specific negative priming effect confirms the inhibitory impact of our experimental training and outlines the dissociation of inhibition and logical components.     

Team reasoning and collective rationality: piercing the veil of obviousness

The experiments reported in our target article provide strong evidence of collective utility maximization, and the findings suggest that team reasoning should now be included among the social value orientations used in cognitive and social psychology. Evidential decision theory offers a possible alternative explanation for our results but fails to predict intuitively compelling strategy choices in simple games with asymmetric team-reasoning outcomes. Although many of our experimental participants evidently used team reasoning, some appear to have ignored the other players' expected strategy choices and used lower-level, nonstrategic forms of reasoning. Standard payoff transformations cannot explain the experimental findings, nor team reasoning in general, without an unrealistic assumption that players invariably reason nonstrategically.     

Satisficing rationality: In praise of folly

Conclusion From a psychological point of view, human wants and desires form a multitiered structure. If values are related in any way to human affectivity or desire - and this is something most maximizing theorists would certainly not dispute - then we are forced to recognize that human values also form a multi-tiered structure. Failure to appreciate this connection leads maximization theorists seriously astray, both in their interpretation of human behavior and in their postulates of rationality. Optimizing involves satisficing, not strictly maximization; satisficing is truly rational.I thank David Schmidtz and Jan Narveson, and the participants of a colloquium at the University of British Columbia, for helpful comments on earlier drafts of this essay.     

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.     

Relevance-driven information search in "pseudodiagnostic" reasoning

When faced with two competing hypotheses, people sometimes prefer to look at multiple sources of information in support of one hypothesis rather than to establish the diagnostic value of a single piece of information for the two hypotheses. This is termed pseudodiagnostic reasoning and has often been understood to reflect, among other things, poor information search strategies. Past research suggests that diagnostic reasoning may be more easily fostered when participants seek data to help in the selection of one of two competing courses of action as opposed to situations where they seek data to help infer which of two competing hypotheses is true. In the experiment reported here, we provide the first empirical evidence demonstrating that manipulating the relevance of the feature for which participants initially receive information determines whether they will make a nominally diagnostic or pseudodiagnostic selection. The discussion of these findings focuses on implications for the ability to engage in diagnostic hypothesis testing.     

In search of remembrance: evidence for memory in visual search

Observers searched for a target among distractors while the display items traded places every 110 ms. Search was slower when the target was always relocated to a position previously occupied by a distractor than when the items remained in place, showing the importance of memory for locations in a visual search task. Experiment 2 repeated a previous study in which items could move to any location within the display, but used a larger range of set sizes than tested in the earlier study. A cost in search times to relocating items was found at the larger set sizes, most likely reflecting that the probability that the target would replace a distractor increased witht he set size. The findings provide strong evidence for the role of memory for locations within trials in a visual search task.     

In two minds: dual-process accounts of reasoning

Researchers in thinking and reasoning have proposed recently that there are two distinct cognitive systems underlying reasoning. System 1 is old in evolutionary terms and shared with other animals: it comprises a set of autonomous subsystems that include both innate input modules and domain-specific knowledge acquired by a domain-general learning mechanism. System 2 is evolutionarily recent and distinctively human: it permits abstract reasoning and hypothetical thinking, but is constrained by working memory capacity and correlated with measures of general intelligence. These theories essentially posit two minds in one brain with a range of experimental psychological evidence showing that the two systems compete for control of our inferences and actions.     

In defense of the rationality of traditions

Alasdair MacIntyre has developed a theory of the rationality of traditions that is designed to show how we can maintain both the tradition-bound nature of rationality, on the one hand, and non-relativism, on the other. However, his theory has been widely criticized. A number of recent commentators have argued that the theory is either inconsistent with his own conception of rationality or else is dependent on the standards of his particular tradition and therefore fails to defuse the threat of relativism. In the present essay, I argue that this objection is mistaken.     

Dibs: In search of self

Abstract

Some ten years ago, while I was training towards ordination as a minister in the Church of England, close friends in the village where I lived took me to a talk given by Michael Jacobs to celebrate the 10th anniversary of the founding of CCC, the Cambridgeshire Consultancy in Counselling, on whose training course my friends, Jenny and David, were then studying.     

In search and proof of human beings, not machines

My intentions are twofold in this autobiographical account. On one hand, I hope to present empirical and theoretical evidence for a freely willing human being. On the other, I carefully record the developing stages I lived through to cement my confidence in the image of humanity I would like my readers to accept. I have, in my career development, worked hard to redefine psychological terminology, defend traditional scientific practices, and provide support for all those colleagues who can no longer stand the mechanistic characterization that so many psychology departments insist on. I have spent over 40 years pursuing such goals. It is not likely that I will ever give up my quest for what I take to be a genuine humanity.     

In search of templates

This study reflects a recent shift towards the study of early stages of expert memory acquisition for chess positions. Over the course of 15 sessions, two subjects who knew virtually nothing about the game of chess were trained to memorise positions. Increase in recall performance and chunk size was captured by power functions, confirming predictions made by the template theory [Cogn. Psychol. 31 (1996) 1; Memory 6 (1998) 225; Cogn. Sci. 24 (2000) 651]. The human data were compared to that of a computer simulation run on CHREST (Chunk Hierarchy and REtrieval STructures), an implementation of the template theory. The model accounts for the pattern of results in the human data, although it underestimates the size of the largest chunks and the rate of learning. Evidence for the presence of templates in human subjects was found.     

In search of miracles

The movie The Third Miracle invites theological reflection on miracles, sainthood, and faith. A movie filled with Lutheran themes of unmerited grace and blessings of the ordinary life, the story line follows a Catholic priest tasked with exploring the authenticity of reported miracles associated with a lay woman and a bleeding statue. Faith and miracles are shown in their ordinariness, easily missed without the eye of faith, and sainthood is juxtaposed with the expected and unexpected vis‐à‐vis motherhood.     

In search of origins

Martin Bernal, Black Athena: The Afroasiatic Roots of Classical Civilization. 2 vols. Rutgers University Press, New Brunswick, 1987–1991. Vol. 1, pp. 575. Vol. 2, pp. 736. ISBN vol. 1 0–8135–1276‐X, 0–8135–1277 (paperback); vol. 2 0–8135–1583–1, 0–8135–1584‐X (paperback). Price: $17.95 per volume.     

In search of depth

Four experiments designed to investigate a visual search task are reported. In each experiment, subjects searched for either a two-dimensional shape rotated in depth among frontal-parallel distractors or a frontal-parallel shape among distractors that were rotated in depth. The principal independent variable was search-set size. In addition, over the four experiments, a variety of spatial arrangements and two axes of rotation in depth were sampled. The chief aim of the experiments was to adduce evidence bearing on the attentional demands of searching for depth. The slopes of the reaction-time (RT) functions were taken as diagnostic. Experiments 1-3 exhibited positive slopes for the RT-set-size function. These slopes appear to be due to a conscious adoption of a serial search strategy by the subjects. When this tendency was suppressed by the procedures of Experiment 4, the slope of the RT-set-size functions did not differ significantly from zero. We conclude that, in agreement with the findings of other studies, slant-in-depth can be detected preattentively.