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991.
992.
20世纪欧洲大陆思想发展过程中一直有一种最为怪癖的现象,就是对自然科学缺乏研究。的确,科学文献似乎否认哲学有超乎生活经验的立足点,并力求以这种方式采取一种客观陈述的姿态。分析的科学哲学采取了这种表面上有价值的姿态,并且以文化和历史要素相结合为代价而得以发展。分析的科学哲学家们把他们的工作看作是使自然科学的方法形式化,他们的兴趣不是专注于文化的、历史的和个人的因素能够成为决定因素的发现过程以及其他领域。然而,科学的知识也像一切知识一样,涉及对某人揭示(诉说)某事。科学探讨意义,这些意义就是体现在语… 相似文献
993.
一、有关技术的传统概念技术不过是人的劳作而已。它既是一种人为的事物也是一种人为的发明过程,其目的是由人制定的,从而也是由人所贯彻的。这就是从古至今技术的哲学人类学背景:从柏拉图的《普罗泰戈拉篇》到卡普(Kapp)和该伦(Gehlen)。他们都将技术说成是必然,因为人是一种有缺陷的生灵,而且他们对技术目的也都是在这样的标题下进行讨论,如加强、延伸以及替代我们可怜的人类器官或肢体,为的是生存竞争或改善我们的境况。但是,这种对技术的传统理解过于狭窄了,因为它没有涵盖这些东西,如教堂的建造、金字塔和庙宇,这些东… 相似文献
994.
Macdonall J 《Journal of the experimental analysis of behavior》1999,71(1):57-74
Concurrent procedures may be conceptualized as consisting of two pairs of schedules with only one pair operating at a time. One schedule of each pair arranges reinforcers for staying in the current alternative, and the other schedule arranges reinforcers for switching to the other alternative. These pairs alternate operation as the animal switches between choices. This analysis of the contingencies suggests that variables operating within an alternative produce behavior that conforms to the generalized matching law. Rats were exposed to one pair of stay and switch schedules in each condition, and the probabilities of reinforcement varied across conditions. Both run length and visit duration were power functions of the ratio of the probabilities of reinforcement for staying and switching. The local model, a model of performance on concurrent procedures, was derived from this power function. Performance on concurrent schedules was synthesized from the performances on the separate pairs. Both the generalized matching law and the local model fitted the synthesized concurrent performances. These results are consistent with the view that the contingencies in the alternative, the probability of stay and switch reinforcement, are responsible for performance consistent with the generalized matching law. These results are compatible with momentary maximizing and molar maximizing accounts of concurrent performance. Models of concurrent performance that posit comparisons among the alternatives are not easily applied to these results. 相似文献
995.
Two studies examined potential age-related differences in attentional capture. Subjects were instructed to move their eyes as quickly as possible to a color singleton target and to identify a small letter located inside it. On half the trials, a new stimulus (i.e., a sudden onset) appeared simultaneously with the presentation of the color singleton target. The onset was always a task-irrelevant distractor. Response times were lengthened, for both young and old adults, whenever an onset distractor appeared, despite the fact that subjects reported being unaware of the appearance of the abrupt onset. Eye scan strategies were also disrupted by the appearance of the onset distractors. On about 40% of the trials on which an onset appeared, subjects made an eye movement to the task-irrelevant onset before moving their eyes to the target. Fixations close to the onset were brief, suggesting parallel programming of a reflexive eye movement to the onset and goal-directed eye movement to the target. Results are discussed in terms of age-related sparing of the attentional and oculomotor processes that underlie attentional capture. 相似文献
996.
Data from a survey of 869 students aged 11 to 15 years and attending six urban middle schools were analyzed to identify differences in sex attitudes and behaviors between self-reported very religious students and their less religious peers. The two groups were demographically similar. They differed on only two attitude items, one suggesting that intercourse was a normal part of teenage dating and the other suggesting intercourse was alright if the two people were in love. The groups did not differ in their estimation of their peers' sexual activity or attitude or in terms of their own intercourse behavior or future intentions. 相似文献
997.
An illusion similar to the stationary visual phantom illusion presented earlier by Gyoba (1983, Vision Research 23 205-211) is reported. This illusion is visible in photopic vision and we have tentatively named it the 'photopic phantom illusion'. A typical example of this illusion is a white and light-gray square-wave grating occluded by a black region. In this figure, a phantom grating running across the occluder with clear contours but less contrast, is seen. The critical spatial frequencies of photopic phantoms have been measured and compared with those of scotopic phantoms that have been reported previously, revealing a great resemblance between them. We discuss the characteristics of this illusion in terms of transparency, stereoscopic viewing, and perceptual completion. 相似文献
998.
In the Poggendorff illusion, two colinear segments abutting obliquely on an intervening configuration (often consisting of two long parallel lines) appear misaligned. We report here the results of a component analysis of the illusion and several of its variants, including in particular the 'corner-Poggendorff' illusion, and variants with a single arm. Using a nulling method, we determined an 'orientation profile' of each configuration, that is, how the illusions varied as the configuration was rotated in the plane of the display. We were able to characterise a pure-misalignment component (having peaks and dips around the +/- 22.5 degrees and +/- 67.5 degrees orientations of the arms) and a pure misangulation component of constant sign, having peaks at the +/- 45 degrees orientations of the arms. Both these components were present in both the classic and the corner-Poggendorff configurations. Thus, the misangulation component appears clearly in the classic Poggendorff illusion, once the misalignment component is partitioned out. Similarly, the corner-Poggendorff configuration, which essentially estimates a misangulation component, contains a misalignment component which becomes apparent once the misangulation is nulled. While our analysis accounts for much of the variability in the shapes of the profiles, additional assumptions must be made to explain the relatively small misangulation measured in the corner-Poggendorff configuration (1.5 degrees, on average, at peak value), and the relatively large illusion measured in the configurations with a single arm (above 6 degrees, on average, at peak values). We invoke the notion that parallelism and colinearity detectors provide counteracting cues, the first class reducing misangulation in the corner-Poggendorff configuration, and the second class reducing the illusion in the Poggendorff configurations with two arms. 相似文献
999.
Circularly repeating patches containing sawtooth luminance gradients produce a sensation of motion when viewed in the periphery. Illusory motion is perceived in a dark-to-light direction, but only when one's gaze is directed to different locations around the stimulus, a point outside the display is fixated and the observer blinks, or when the stimulus is sequentially displayed at different locations whilst the observer fixates one point. We propose that the illusion is produced by the interaction of three factors: (i) introducing transients as a result of eye movements or blinks; (ii) differing latencies in the processing of luminance; and (iii) spatiotemporal integration of the differing luminance signals in the periphery. 相似文献
1000.
Green L Myerson J Ostaszewski P 《Journal of experimental psychology. Learning, memory, and cognition》1999,25(2):418-427
Previous research has shown that the value of large future rewards is discounted less steeply than is the value of small future rewards. These experiments extended this line of research to probabilistic rewards. Two experiments replicated the standard findings for delayed rewards but demonstrated that amount has an opposite effect on the discounting of probabilistic rewards. That is, large probabilistic amounts were discounted at the same or higher rates than small amounts. Although amount had opposite effects on the discounting of delayed and probabilistic rewards, nevertheless, the same form of mathematical function accurately described discounting of both types of reward. The findings suggest that fundamentally similar, but not identical, processes are involved in decision making regarding delayed and probabilistic rewards. The implications of these findings for impulsivity and self-control are discussed. 相似文献