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Aristotle claims at Eudemian Ethics 1.2 that everyone who can live according to his own choice should adopt some goal for the good life, which he will keep in view in all his actions, for not to have done so is a sign of folly. This is an opinion shared by other ancients as well as some moderns. Others believe, however, that this view is false to the human condition, and provide a number of objections: (1) you can't plan love; (2) nor life's surprises; (3) planning a whole life is of no use since the world changes too much; (4) as do our values; and (5) planning a life is something only dreary people would do. The aim of this paper is to examine these objections, as part of a broader attempt to defend the relevance of a eudaimonistic approach to the question of how to live well.  相似文献   
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Low-income mothers in the U.S. are more likely to experience postpartum depression (PPD) and less likely to seek treatment than their middle-class counterparts. Despite this knowledge, prior research has not provided an in-depth understanding of PPD symptoms as they are experienced by low-income mothers. Through in-depth interviews, this study investigated low-income mothers' ( n  = 19) experiences and explanatory frameworks for their PPD symptoms. Grounded theory analysis uncovered five main categories that linked the participants' PPD symptoms to their lived experiences of mothering in poverty, including: (1) ambivalence, (2) caregiving overload, (3) juggling, (4) mothering alone, and (5) real-life worry. The analysis further located the core experience of PPD for low-income mothers as "feeling overwhelmed" due to mothering in materially and socially stressful conditions. These findings challenge the prevailing biomedical discourse surrounding PPD and situate mothers' symptoms in the context of the material hardships associated with living in poverty.  相似文献   
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Observers viewed the optical flow field of a rotating quadric surface patch and were required to match its perceived structure by adjusting the shape of a stereoscopically presented surface. In Experiment 1, the flow fields included rigid object rotations and constant flow fields with patterns of image acceleration that had no possible rigid interpretation. In performing their matches, observers had independent control of two parameters that determined the surface shape. One of these, called the shape characteristic, is defined as the ratio of the two principle curvatures and is independent of object size. The other, called curvedness, is defined as the sum of the squared principle curvatures and depends on the size of the object. Adjustments of shape characteristic were almost perfectly accurate for both motion conditions. Adjustments of curvedness, on the other hand, were systematically overestimated and were not highly correlated with the simulated curvedness of the depicted surface patch. In Experiment 2, the same flow fields were masked with a global pattern of curl, divergence, or shear, which disrupted the first-order spatial derivatives of the image velocity field, while leaving the second-order spatial derivatives invariant. The addition of these masks had only negligible effects on observers’ performance. These findings suggest that observers’ judgments of three-dimensional surface shape from motion are primarily determined by the second-order spatial derivatives of the instantaneous field of image displacements.  相似文献   
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