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971.
The influence of prior, irretrievable, investment (sunk cost) on commitment to medical treatment was investigated. Three studies were run investigating the influence of sunk cost in the form of money, time, and effort. A total of 637 participants (314 male) with a mean age of 19.58 years were recruited from an undergraduate population. A computer program simulated the process of arranging a course of physiotherapy. Participants invested one of three amounts of sunk cost (under budget, on budget, or over budget) into arranging sessions with a chiropractor. Participants then decided how much time they wished to commit to these chiropractor sessions or to an alternative treatment with a better chance of success. Results revealed a significant effect of invested money, a significant effect of invested effort, but no effect of invested time. Invested money produced a sunk cost effect, while invested effort appeared to exert influence via cognitive dissonance. The implications for healthcare decision-making are discussed.  相似文献   
972.
The aim of this paper is to show that it’s not a good idea to have a theory of truth that is consistent but ω-inconsistent. In order to bring out this point, it is useful to consider a particular case: Yablo’s Paradox. In theories of truth without standard models, the introduction of the truth-predicate to a first order theory does not maintain the standard ontology. Firstly, I exhibit some conceptual problems that follow from so introducing it. Secondly, I show that in second order theories with standard semantics the same procedure yields a theory that doesn’t have models. So, while having an ω- inconsistent theory is a bad thing, having an unsatisfiable theory of truth is actually worse. This casts doubts on whether the predicate in question is, after all, a truthpredicate for that language. Finally, I present some alternatives to prove an inconsistency adding plausible principles to certain theories of truth.  相似文献   
973.
Preface     
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974.
Anna Pautz has recently argued that the pretense theory of thought about fiction cannot explain how two people can count as thinking about the same fictional character. This is based on conflating pretending and the serious thought that can be based on pretend. With this distinction in place, her objections are groundless.  相似文献   
975.
When people scan mental images, their response times increase linearly with increases in the distance to be scanned, which is generally taken as reflecting the fact that their internal representations incorporate the metric properties of the corresponding objects. In view of this finding, we investigated the structural properties of spatial mental images created from nonvisual sources in three groups (blindfolded sighted, late blind, and congenitally blind). In Experiment 1, blindfolded sighted and late blind participants created metrically accurate spatial representations of a small-scale spatial configuration under both verbal and haptic learning conditions. In Experiment 2, late and congenitally blind participants generated accurate spatial mental images after both verbal and locomotor learning of a full-scale navigable space (created by an immersive audio virtual reality system), whereas blindfolded sighted participants were selectively impaired in their ability to generate precise spatial representations from locomotor experience. These results attest that in the context of a permanent lack of sight, encoding spatial information on the basis of the most reliable currently functional system (the sensorimotor system) is crucial for building a metrically accurate representation of a spatial environment. The results also highlight the potential of spatialized audio-rendering technology for exploring the spatial representations of visually impaired participants.  相似文献   
976.
Extensionality and Restriction in Naive Set Theory   总被引:1,自引:0,他引:1  
Zach Weber 《Studia Logica》2010,94(1):87-104
The naive set theory problem is to begin with a full comprehension axiom, and to find a logic strong enough to prove theorems, but weak enough not to prove everything. This paper considers the sub-problem of expressing extensional identity and the subset relation in paraconsistent, relevant solutions, in light of a recent proposal from Beall, Brady, Hazen, Priest and Restall [4]. The main result is that the proposal, in the context of an independently motivated formalization of naive set theory, leads to triviality.  相似文献   
977.
Blocked designs in functional magnetic resonance imaging (fMRI) are useful to localize functional brain areas. A blocked design consists of different blocks of trials of the same stimulus type and is characterized by three factors: the length of blocks, i.e., number of trials per blocks, the ordering of task and rest blocks, and the time between trials within one block. Optimal design theory was applied to find the optimal combination of these three design factors. Furthermore, different error structures were used within a general linear model for the analysis of fMRI data, and the maximin criterion was applied to find designs which are robust against misspecification of model parameters.  相似文献   
978.
979.
Hijab, the practice of modesty or "covering," is one of the most visible and controversial aspects of Islam in the twenty-first century, partly because the Qur'an offers so little guidance on proper dress. This forces Muslims to engage in ijtihad (interpretation), which historically has resulted in vast differences in dress around the world. By transcending some of the boundaries of space, time and the body, the Internet has emerged as a place where Muslims from diverse backgrounds can meet to debate ideas and flesh them out through shared experiences. After discussing hijab in the Qur'an and other traditional sources, this article explores the use of cyberspace as a multi-media platform for learning about and debating what constitutes appropriate Islamic dress. The last section focuses on a case study of the multi-user "hijablog" hosted by thecanadianmuslim.ca, which represents one of the largest in-print discussions on hijab ever recorded in the English language. On this blog and other forums like it, ijtihad has become a critical tool for debate on matters such as hijab, which are important but sparsely discussed in the Qur'an.  相似文献   
980.
Recent social surveys of happiness (subjective well-being) have given a new stimulus to utilitarian political theory by providing a statistically reliable measure of the ‘happiness’ of individuals that can then be correlated with other variables. One general finding is that greater happiness does not correlate strongly with increased wealth, beyond modest levels, and this has led to calls for governments to shift priorities away from economic growth and towards other social values. This paper notes how the conclusions of this research help to address some of the traditional objections to utilitarianism. The question of how happiness research findings can be used to set happiness-maximization goals for public policy needs careful examination, as the translation from research to policy is not always straightforward. Some empirical and ethical objections to this ‘new utilitarianism’ are raised. The complicating factors of public expectations of, and trust in, governments pose obstacles to any proposal that happiness research may lead to changes in public policy and hence to ‘happier’ populations.  相似文献   
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