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Conclusion I have shown (to my satisfaction) that Leibniz's final attempt at a generalized syllogistico-propositional calculus in the Generales Inquisitiones was pretty successful. The calculus includes the truth-table semantics for the propositional calculus. It contains an unorthodox view of conjunction. It offers a plethora of very important logical principles. These deserve to be called a set of fundamentals of logical form. Aside from some imprecisions and redundancies the system is a good systematization of propositional logic, its semantics, and a correct account of general syllogistics. For 1686 it was quite an accomplishment. It is a pity that Leibniz himself did not fully appreciate what he had achieved. It does seem to me that this was due in part, as the Kneales urge (Note 4), to his having kept the focus of his attention on traditional syllogistics. It is a great pity that he did not polish GI 195–200 for publication. The publication of GI 195, 198, and 200 would have most likely promoted further research.This paper was conceived in a Seminar on the Generales Inquisitiones offered by Professor Klaus Jacobi at the University of Freiburg during the 1987 winter semester. I am grateful to him for having allowed me to participate in that exciting seminar. I am grateful to all the seminar participants, especially to Professor Jacobi, Professor Klaus Erich Kaehler, Doctor Helmut Pape, and Herr Hans-Peter Engelhart for sustained and illuminating discussions of some passages of the GI. Jacobi was extremely kind in reading the second version of this paper with a highly refined comb. I am most grateful to him for having pointed out typos, stylistic infelicities, and conceptual obscurities. He also provided advice on the translation, and, most generously and cooperatively, offered suggestions for improving the exposition and the arguments.  相似文献   
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The purpose of the paper is to present a logical framework that allow to formalize a kind of prima facie duties, defeasible conditional duties, indefeasible conditional duties and actual (indefeasible) duties, as well as to show their logical interconnections.  相似文献   
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Examination of boundary regulation can provide family therapists with a framework to describe both the functioning of family systems and personal systems (i.e., the intrapsychic functioning of individual family members). In the present study, late adolescents' perceptions of boundary regulation within their family systems (i.e., ratings of family health, communication, leadership, expressiveness, cohesion, and family conflict) were related to regulation of their personal boundaries (i.e., self-reported personal competence, distress, and patterns of defense mechanism use). In addition, personal system variables reliably discriminated between adolescents who described their families as psychologically healthy versus psychologically unhealthy.  相似文献   
65.
通过在自然光照射下,测定不同年龄的学前儿童在不同的工作面照度与不同的工作面照度分布情况下,在规定时间内从红色、黄色、绿色3种球状PVC塑料颗粒的混合物中分拣出绿色颗粒的多少,来探讨电磁波谱中的可见光部分对学前儿童操作技能的影响。为创造适宜学前儿童进行操作训练的健康环境提供依据。  相似文献   
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为考察初中生友谊质量与孤独感的变化轨迹及两者间的关系,采用关系网络问卷、孤独感量表对西安市的875名初中生(M=12.73±0.18;男生494名)进行三年追踪测量,使用多元潜变量增长模型进行分析。结果发现:(1)初中三年,中学生的友谊质量逐渐提高,孤独感水平逐渐下降;(2)初一时的友谊质量和孤独感水平存在显著的个体差异,初中三年期间二者的发展速度也存在个体差异;(3)初一时的友谊质量可显著预测初一时的孤独感水平(β=-1.77,p<0.001)及随后的发展速度(β=0.20,p<0.05);(4)男生的孤独感水平初始值高于女生,友谊质量的初始值则低于女生;高SES个体孤独感的起始值高于低SES个体。本研究结果揭示了初中三年期间个体友谊质量与孤独感的动态变化关系及友谊质量对孤独感的预测作用,对改善青少年孤独感的现状有一定的现实指导意义。  相似文献   
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本实验通过对CIE 1960均匀色度图黑体轨迹不同区域的色温点∞K、8333K、4167K的视觉评价,探讨这一色度图的均匀性。 我们用了两个被试,分别对视觉色度计2°视野的两半视场进行颜色匹配。两位被试得到相同的结果(1)不同色温点的同一视觉等级图形的形状和大小各不相同,表明CIE1960均匀色度图的黑体轨迹区域不够均匀,(2)∞K和8333K色温点的相同视觉等级长度都不相等,而4167K色温相等。可以认为,1960年均匀色度图在4167K的较小范围内的均匀性较好。  相似文献   
70.
Based on the recruitment experience in a family therapy research project with heroin addicts, this paper explores the difficulties of researcher networking with other social service agencies. Concepts from contextual family therapy are used to explore four general areas that contribute to successful intra-agency relationships: 1) Evaluating the nature of larger system relationships; 2) identifying the resources and needs of a clinic; 3) joining with the counseling staff; and 4) addressing the impact of public policy and ideology on clinic life. A case of engaging one clinic is presented and nine guidelines for engaging large community settings for participation in family therapy research are offered. These areas are considered in light of the relational dynamics that arise when working with multiple social service systems.An earlier version of this paper was presented at the American Family Therapy Association conference in Washington, DC, June 1986. The authors are grateful to the recruitment staff of the Intergenerational Family Therapy Project: Guillermo Lopez, Bart Rubin, Sharara Godfry, and Armando Chenyek. This research was supported in part by a grant to Guillermo Bernal from the National Institute on Drug Abuse (DA03543).  相似文献   
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