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971.
TIM DE MEY 《Metaphilosophy》2006,37(2):222-239
Abstract: In part because “imagination” is a slippery notion, its exact role in the production of scientific knowledge remains unclear. There is, however, one often explicit and deliberate use of imagination by scientists that can be (and has been) studied intensively by epistemologists and historians of science: thought experiments. The main goal of this article is to document the varieties of thought experimentation, not so much in terms of the different sciences in which they occur but rather in terms of the different functions they fulfil. I argue that thought experimentation (and hence imagination) plays a role not only in theory choice but in singular causal analysis and scientific discovery as well. I pinpoint, moreover, some of the rules governing the use of thought experiments in theory choice and in singular causal analysis, that is, some of the criteria they should meet in order to fulfil those functions successfully.  相似文献   
972.
Previous research in a water-reinforced instrumental training situation with toads (Bufo arenarum) has shown that performance in both acquisition and extinction is poorer after partial, rather than continuous reinforcement training. In Experiment 1, the performance of a group receiving 24 trials on a 50% partial reinforcement schedule was poorer in acquisition and extinction than that of continuously reinforced groups matched for trials or reinforcements. However, partially reinforced toads extinguished at the same rapid rate as a continuously reinforced group that received training only on the days in which the partial toads received water reinforcement. In Experiment 2, extinction was faster after 10 reinforced acquisition trials than after 30 trials. This evidence suggests that the deleterious effects of partial reinforcement in toads can be explained by a combination of two factors, namely, the distribution of reinforced trials across days and the total number of reinforcements.  相似文献   
973.
Abstract: The nature of fantasy has been little discussed, despite its importance in the arts. Its significance is brought out here in relation to the long‐standing debate on the alleged paradox of fiction—that we respond emotionally to characters and events known to be unreal. Examination of the paradox shows it to be ill founded once the nature of fantasy is appreciated. Moreover, a detailed consideration of fantasy shows that it can itself provide a plausible account of our emotional reactions to creative literature, an account that, after a review of some possible objections, is then contrasted with the leading contemporary theories.  相似文献   
974.
Abstract: This article raises the question of how the ontological status of virtual objects bears on their intrinsic value. If virtual objects are unreal or less real than physical objects, does it mean that they will have less intrinsic value? If they have intrinsic value, what are the explanations for this value, and how do they relate to the ontological status of the virtual objects? First, the article reviews recent work concerning the ontological status of virtual reality and virtual objects. Second, it argues that in some cases the ontological status of virtual objects does undermine the value placed in them, in that the objects can fail to have the properties that ground the value attributions made to them, while in other cases their ontological status is not important. Finally, the article relates the grounding of value attributions to philosophical theories of value, in particular, perfectionism and hedonism.  相似文献   
975.
This paper deals with optimal partitioning of limited testing time in order to achieve maximum total test score. Nonlinear optimization theory was used to analyze this problem. A general case using a generic item response model is first presented. A special case that applies a response time model proposed by Wang and Hanson (2005) is also presented. Theoretical properties of the optimal solution are derived. Their practical implications to optimal test-taking strategies are also discussed. The theoretical properties are in general agreement with the conventional advice to the examinees on pacing strategy.  相似文献   
976.
977.
This paper explores the impact of the Al-Aqsa Intifada on tolerance orientations of the Israeli Jewish public. We rely upon five surveys carried out between January 2000 and June 2002 to study in a real-life setting the amount and nature of change in political tolerance due to the conflict and the mechanisms behind it. Building on theory and research on intergroup relations in social psychology and political tolerance in political science, we focus upon threat and ingroup identification as the two primary factors in the social psychological processes resulting from conflict and leading to intolerance. We set the trends and explore mediation and interaction processes in the impact of this round of conflict on political tolerance.  相似文献   
978.
聋童执行功能发展:聋童与正常儿童的比较   总被引:6,自引:0,他引:6  
利用标准Dimensional Change Card Sort任务(DCCS),对76名智力正常的3~8岁聋童和78名3~5.5岁的正常儿童进行了对比测试,旨在考察聋童执行功能发展的年龄特征与发展水平。结果发现,3岁组的聋童和正常儿童在DCCS任务上的表现没有显著性差异,但正常儿童在4~4.5岁时进入一个迅速发展期,而聋童要在6岁时才有快速的发展,到7岁后才相当于正常儿童5岁的发展水平,大约滞后2年。研究认为,造成聋童执行功能发展滞后的原因主要有:(1)语言符号系统和聋童特有的符号系统之间可能存在的差异;(2)聋童可能存在计划和灵活性的缺陷;(3)聋童可能存在命名和标识策略上的困难和注意机制的缺陷。结合关于聋童心理理论发展滞后于正常儿童7年以上的报道,心理理论发展和执行功能发展在聋童身上表现出较大的不一致性。  相似文献   
979.
Carl S. Helrich 《Zygon》2006,41(3):543-566
Abstract. I present a partially historical discussion of the basis of the quantum theory in nonmathematical terms using human knowledge and consciousness as an underlying theme. I show that the philosophical position in both classical and quantum theory is the experimental and mathematical philosophy of Isaac Newton. Because almost all the systems we deal with are multicomponent, we must consider the limitations and openness imposed by thermodynamics on our claims in both classical and quantum treatments. Here the reality of measurement stands in the way of any simple picture but also provides the basis for considerations of free will. Particular care is taken with the concepts of quantum measurement, entanglement, and decoherence because of their importance in the discussion.  相似文献   
980.
We establish a connection between the geometric methods developed in the combinatorial theory of small cancellation and the propositional resolution calculus. We define a precise correspondence between resolution proofs in logic and diagrams in small cancellation theory, and as a consequence, we derive that a resolution proof is a 2-dimensional process. The isoperimetric function defined on diagrams corresponds to the length of resolution proofs.  相似文献   
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