We report two studies on the effect of implicitly versus explicitly conveying affirmation and denial problems about conditionals. Recently Evans and Handley (1999) and Schroyens et al. (1999b, 2000b) showed that implicit referencing elicits matching bias: Fewer determinate inferences are made, when the categorical premise (e.g., B) mismatches the conditional's referred clause (e.g., A). Also, the effect of implicit affirmation (B affirms not-A) is larger than the effect of implicit denial (B denies A). Schroyens et al. hypothesised that this interaction (...) is due to uncertainty in the case-wise affirmation of the contrast class of negated elements involved in implicit affirmations. In Experiment 1 we tested this hypothesis by manipulating the set size of the conditional clauses. The results confirm that binary sets, where the contrast class is a singleton, eliminate the differential effect of implicit affirmation and denial. With non-binary sets the interaction is not modulated by the scope of the contrast class (3, 5, 9 elements). Experiment 2 further investigated the role of contrast classes by using class inclusion to construct implicit affirmations (Mammal vs Mammal or Monkey) and implicit denial (No-Mammal vs Mammal or Monkey), in addition to the standard implicit problems mediated by contrast-class inclusion [(No-)Mammal/No-Mammal; Reptile; Snake). Findings indicate that class inclusion (Mammal/Monkey; Reptile/ Snake) only marginally affects performance, and is independent of the type of problem. This would suggest that the implicitness problem-type interaction is dependent on constructing contrast classes. However, the experiment failed to replicate the interaction, even on the subset of problems repeating the abstract letter/number format of Experiment 1. Moreover, with the natural binary set-sizes (vowels/consonants) the implicitness effect was eliminated entirely. (shrink)
The main thrust of my argument was that ad hoc su gge s ti ons of ch a ri ty cannot replace a systematic and theoreti c a lly inform ed approach to poverty rel i ef . Ch a ri t a ble don a ti on som eti m e s h elps—and som etimes harm s — but is no general solution to global poverty, and can be po s i tively dangerous wh en pre s en (...) ted as such. We need to consider, and often choose, other routes to helping the poor—including ethical to u rism and fair trade in lu x u ry goods. We will not be able to invest in such feasible routes if we give away all our extra income, as Singer recommends. Sticking to donation above all, when a combination of other strategies is necessary, is highly likely to harm the poor. Si n ger doe s n’t re a lly en ga ge my argumen t . In s te ad , he cari c a tu res our “f u n d a m ental disa greem en t” :a pp a ren t ly, Si n ger rej ects va ri o u s policies because he takes into account the “f act s” ; wh ereas Ku per is the one seeking a “f a i t h ,” a “po l i tical ph i l o s ophy. . . i m mune to ref ut a ti on on the basis of evi den ce .” Anyon e who has re ad my arti cle (pp. 1 07 - 2 0) must ﬁn d this puzzling. The arti cle explains at len g t h wh i ch kinds of b ack ground theories help us to d i s cern and re s pon s i bly con s i der the rel eva n t f act s . I show that Si n ger sel ects and uses fact s u n c ri ti c a lly prec i s ely because he has no po l i tical econ omy, no po l i tical soc i o l ogy, and no t h eory of ju s ti ce . We are seri o u s ly misled if we do not draw adequ a tely on the wi s dom and.. (shrink)
Two types of truth table tasks are used investigating mental representations of conditionals: a possibilities-based and a truth-based one. In possibilities tasks, participants indicate whether a situation is possible or impossible according to the conditional rule. In truth tasks participants evaluate whether a situation makes the rule true or false, or is irrelevant with respect to the truth of the rule. Comparing the two-option version of the possibilities task with the truth task in Experiment 1, the possibilities task yields logical (...) answer patterns whereas the truth task yields defective patterns. Adding the irrelevant option to the possibilities task in Experiment 2 leads to a considerable amount of defective patterns in the possibilities task, but still to more logical patterns in the possibilities task than in the truth task. Experiment 3 shows that directionality matters since rule-to-situation tasks yield more logical answer patterns than do situation-to-rule tasks. We conclude that both task types are not comparable as such since wording, number of options and directionality influence the results. (shrink)
The essays appearing in these two volumes are based on Keynote and State-of-the-Art Lectures delivered at the XXVth International Congress of Psychology, in Brussels, July 1992. The Brussels Congress was the latest in a series of conferences which are organized at regular intervals under the auspices of the International Union of Psychological Science, the main international organization in the field of Scientific Psychology. The first of those meetings took place in Paris in 1889. An important function of the International Congresses (...) is to promote communication between different specializations in Psychology. Speakers were therefore asked to present lectures and discussions in their own fields of study, in a way that would be accessible to fellow psychologists active in other fields. State-of-the-Art lecturers were specifically asked to prepare a tutorial review on a topic which, in the view of the Program Committee, had recently given rise to particularly important developments. These contributions are included in Volume Two. Keynote lecturers were left free to address whatever subject they felt was of greatest interest. The chapters in Volume 1 are preceded by the Presidential Address by Mark R. Rosenzweig. (shrink)
In certain contexts reasoners reject instances of the valid Modus Ponens and Modus Tollens inference form in conditional arguments. Byrne (1989) observed this suppression effect when a conditional premise is accompanied by a conditional containing an additional requirement. In an earlier study, Rumain, Connell, and Braine (1983) observed suppression of the invalid inferences "the denial of the antecedent" and "the affirmation of the consequent" when a conditional premise is accompanied by a conditional containing an alternative requirement. Here we present three (...) experiments showing that the results of Byrne (1989) and Rumain et al. (1983) are influenced by the answer procedure. When reasoners have to evaluate answer alternatives that only deal with the inferences that can be made with respect to the first conditional, then suppression is observed (Experiment 1). However, when reasoners are also given answer alternatives about the second conditional (Experiment 2) no suppression is observed. Moreover, contrary to the hypothesis of Byrne (1989), at least some of the reasoners do not combine the information of the two conditionals and do not give a conclusion based on the combined premise. Instead, we hypothesise that some of the reasoners have reasoned in two stages. In the first stage, they form a putative conclusion on the basis of the first conditional and the categorical premise, and in the second stage, they amend the putative conclusion in the light of the information in the second premise. This hypothesis was confirmed in Experiment 3. Finally, the results are discussed with respect to the mental model theory and reasoning research in general. (shrink)
Each chapter of this beginning textbook is followed by an extensive list of questions, but bibliography and guides for supplementary source readings are absent. Positions other than St. Thomas's--such as those of Suarez, Scotus, and Kant--are briefly considered on specific issues. --R. D. G.
This volume--one of several in a series on contemporary philosophy in Italy and in the U. S.--presents the principal philosophic and cultural currents in Italy through the works of representative writers. The coverage of philosophy is quite complete. Besides the expected articles on Croce, Gentile, existentialism, neo-scholasticism, and the philosophy of history, there are, among others, articles on analytic philosophy, marxism, and the philosophy of science. The appendix supplies information on Italian philosophic centers, organizations, and journals, as well as brief (...) biographies of the contributors.--R. D. G. (shrink)
Although nature of science and nature of scientific inquiry are related to each other, they are differentiated as NOS is being more related to the product of scientific inquiry which is scientific knowledge whereas NOSI is more related to the process of SI. Lederman et al. determined eight NOSI aspects for K-16 context. In this study, a science camp was conducted to teach scientific inquiry and NOSI to 24 6th and 7th graders. The core of the program was guided inquiry (...) in nature. The children working in small groups under guidance of science advisors conducted four guided-inquiries in the nature in morning sessions on nearby plants, animals, water, and soil. NOSI aspects were made explicit during and at the end of each inquiry session. Views about scientific inquiry questionnaire was applied as pre- and post-test. The results of the study showed that children developed in all eight NOSI aspects, but higher developments were observed in “scientific investigations all begin with a question” and “there is no single scientific method,” and “explanations are developed from data and what is already known” aspects. It was concluded that the science camp program was effective in teaching NOSI. (shrink)
This fourth edition has been enlarged by over 400 pages through the addition of 762 new articles and some revision of a number of others. Bibliographies have been updated, and a chronological table added. The best of its kind in Spanish.--R. D. G.
One of the areas of concern raised by cross-border reproductive travel regards the treatment of women who are solicited to provide their ova or surrogacy services to foreign consumers. This is particularly troublesome in the context of developing countries where endemic poverty and low standards for both medical care and informed consent may place these women at risk of exploitation and harm. We explore two contrasting proposals for policy development regarding the industry, both of which seek to promote ethical outcomes (...) and social justice: While one proposal advocates efforts to minimize cross-border demand for female reproductive resources through the pursuit of national self-sufficiency, the other defends cross-border trade as a means for meeting the needs of vulnerable groups. Despite the conflicting objectives of the proposed strategies, the paper identifies common values and points of agreement between the two, including the importance of regulations to safeguard those providing ova or surrogacy services. (shrink)