Perception of relative depth interval: systematic biases in perceived depth

Given an estimate of the binocular disparity between a pair of points and an estimate of the viewing distance, or knowledge of eye position, it should be possible to obtain an estimate of their depth separation. Here we show that, when points are arranged in different vertical geometric configurations across two intervals, many observers find this task difficult. Those who can do the task tend to perceive the depth interval in one configuration as very different from depth in the other configuration. We explore two plausible explanations for this effect. The first is the tilt of the empirical vertical horopter: Points perceived along an apparently vertical line correspond to a physical line of points tilted backwards in space. Second, the eyes can rotate in response to a particular stimulus. Without compensation for this rotation, biases in depth perception would result. We measured cyclovergence indirectly, using a standard psychophysical task, while observers viewed our depth configuration. Biases predicted from error due either to cyclovergence or to the tilted vertical horopter were not consistent with the depth configuration results. Our data suggest that, even for the simplest scenes, we do not have ready access to metric depth from binocular disparity.     

Russian Philosophers on Continuous Creation as the Basis for Social Change

Vladimir Solov’ëv, Sergej Bulgakov, Nikolaj Berdjaev, and Semën Frank shared the conviction that Creation is incomplete: humanity must arrive at organizing social life on an “eighth day.” Thus they prophesied the Universal Church, “social Christianity,” “personalist socialism,” and “spiritual democracy.” Their attempt to avoid any illegitimate confusion between independent rational thought and Christian faith prompted Bulgakov to become an ordained theologian, Berdjaev a “philosophical poet,” and Frank a “Christian realist.” Solov’ëv’s theosophical attempt to philosophically substantiate faith and consequently eschatological prophecy finds itself in the same tragic predicament as Christian faith in general when amalgamated on a one to one basis with the world. I am to show that this is not the case for any of the three other authors discussed, however, much they did adhere to some of Solov’ëv’s major lines of thought.     

Einige Gedanken zur Logik und ihrer Vermittlung aus gegebenem Anlaß

Journal for General Philosophy of Science - In logic books ordinary language examples are often thought to be easier to understand, as it is presupposed or suggested, that their logical structure...     

Single and multidimensional same-different judgments

A probabilistic, multidimensional Thurstonian model for treating same-different judgments was tested in an experiment in which subjects made single-dimensional and two-dimensional same-different judgments. Strong asymmetries in the data required adding temporal bias parameters to the model. The model, with bias parameters, accounted for the single- and two-dimensional judgments reasonably well, but the parameters were not invariant between the different solutions. The two-dimensional judgments were more variable than expected on the basis of the single-dimensional judgments.     

POLITICAL OBLIGATION,FAIRNESS, AND INDEPENDENCE

In the first section the problem of political obligation is motivated, and in Section 2 the core structure of the problem is laid bare. A recognition of this structure prompts reflection that the problem will appear very different to different thinkers, depending on their moral theories. It also invites the speculation that the problem will be incapable of solution on some moral theories while trivial on others. This polarity does reflect the state of much of the literature until fairly recently. However this picture is seen to be too crude, and in the third section it is shown how an interesting solution has been proposed by advocates of the ‘theory of fairness’. In Section 4 this theory is evaluated, concentrating particularly on George Klosko's version, which is, in part, rejected. However it is argued that no version of the theory is able to guarantee universal political obligations. In Section 5 it is argued that this is an unnoticed advantage of the theory, for it may well be that, morally at least, we should allow those who do not benefit from the existence of the state to escape political obligations. The consequences of this view are examined and found not to be as threatening as they might first have appeared.     

Nondirectiveness and genetic counseling

Nondirectiveness is the generally required and professed standard for genetic counseling. However, studies are lacking in the field of human genetics and in other disciplines which address either the theory or practice of this type of therapeutic procedure in the context of genetic counseling. Moreover, there is no indication the further development this concept has undergone in client-centered therapy has been acknowledged in human genetics. This could be due tot he historical development of genetic counseling, its inherent conflicts and often undefined goals, and the latent need of human geneticists to defend themselves against being accused of eugenic tendencies. Nondirectiveness and directiveness, however, can neither adequately describe what takes place in genetic counseling, nor can they — according to their original meaning — be used to define an ethical standard of genetic counseling. Starting with the writings by Carl Rogers (1942), an experiential approach is described, in which counseling is seen as a process of influence, which is wished by all the persons involved, during which activities are oriented toward the experience of the client, and which allows the counselor to communicate openly and directly with the client. The present study illustrates the use of the experiential approach in genetic counseling and shows that it can uphold the principle of ethics, which nondirectiveness demands and, at the same time, prevent the inevitable and unresolvable contradictions. This means that in their training genetic counselors must learn to recognize and constantly reflect on the influence they can and want to exert. In order to be able to use this influence in a responsible manner, genetic counselors must also learn to have a certain degree of flexibility so that they are able to check at any time how their client responds to this influence.