The irreversibility effect implies that a decision maker who neglects the prospect of receiving more complete information at later stages of a sequential decision problem will in certain cases too easily take an irreversible decision, as he ignores the existence of a positive option value in favour of reversible decisions. This option value represents the decision maker's flexibility to adapt subsequent decisions to the obtained information. In this paper we show that the economic models dealing with irreversibility as used in (...) environmental and capital investment decision making can be extended to emergency response decisions that produce important irreversible effects. In particular, we concentrate on the decision whether or not to evacuate an industrial area threatened by a possible nuclear accident. We show in a simple two-period evacuation decision model that non-optimal conclusions may be drawn when evacuation is regarded as a `now or never decision'. The robustness of these results is verified by means of a sensitivity analysis of the various model parameters. The importance of `options thinking' in this decision context is illustrated in an example. (shrink)

In various letters written to Mersenne in 1640 and 1641, Descartes mentions the Summa philosophiae quadrapartita of Eustachius a Sancto Paulo. But nothing that he says would lead us to believe the work an important influence on his thought. Nonetheless, when we turn to the Summa we are immediately struck by what seem to be “Cartesian” elements in its presentation. For example, a distinction is drawn between formal logic and “natural” logic. Formal logic is seen as a convenience in learning (...) the sciences, but natural logic alone is found to be the absolutely essential requirement. And this natural logic is basically a product of the natural light. It is not difficult to see in these passages a foreshadowing of Descartes’ new conception of method. Like Eustachius, he too maintains that the natural functions of the mind are all that we require in the pursuit of truth. But we shall find even more interesting similarities between the two men. (shrink)

This work is the product of several years of intense study of the various aspects of Kant's work, and the attempt to provide insights for students both with respect to the details of the Kantian system, and into the development and implications of the system as a whole. During that time many individuals have contributed to its ultimate formulation, and I would like to express my appreciation at least to the more generous contributors. For a careful reading of the manuscript (...) in its earlier forms, and suggestions which helped in many ways to improve the work and to crystalize its thesis, I would like to thank Professors Wilbur Long, A. C. Ewing, and Richard Bosley. For their interest and encouragement in the later stages of the project, I must thank Professor Lewis White Beck, and the many students who have taken my Kant seminar at the University of Alberta, especially Mr. Dieter Hartmetz. And finally, 1 acknowledge with pleasure my longstanding debt to Professor William H. Werkmeister for his years of critical advice and encouragement. Perhaps only Kant and my wife have contributed more to my philosophic development. Acknowledgment must also be made of the permission kindly granted by various publishers for the use of material from the following works under their copyright. Kant's Critique of Practical Reason, translated by Lewis White Beck (copyright 1956, by The Liberal Arts Press, Inc. (shrink)

Gebhardt in his brief report1 pleads for patient organisations to establish databanks on medical complications. Given the references and the lack of argumentation, there is substantial danger of misinterpretation of the current situation, which in turn may frustrate the process of increased transparency. We would therefore like to respond to this by giving background information and reasons for some of the choices that were made with respect to the registry of complications mentioned by Gebhardt.First, a distinction needs to be made (...) between an error and an adverse outcome, which are often confused. From Gebhardt’s reference to the journalist’s article which discusses the same registry of adverse outcomes, but with the title referring to errors, both Gebhardt and the journalist think errors and adverse outcomes are the same thing. However, an error refers to the process in which something has gone wrong, a substandard performance, regardless of the outcome. It has been explained by others that such a judgement may have a degree of subjectivity.2 An adverse outcome refers to the outcome which is unwanted but does not necessarily imply that an error has been made. This is why the term “adverse outcomes” is used rather than …. (shrink)

Notwithstanding its overwhelming descriptive power for existing data, it is not clear whether the kinematic theory of Plamondon & Alimi could generate new insights into biomechanical constraints and psychological processes underlying the way organisms trade off speed for accuracy. The kinematic model should elaborate on the role of neuromotor noise and on biomechanical strategies for reducing endpoint variability related to such noise.

We assessed how synchronous speech listening and lipreading affects speech recognition in acoustic noise. In simple audiovisual perceptual tasks, inverse effectiveness is often observed, which holds that the weaker the unimodal stimuli, or the poorer their signal-to-noise ratio, the stronger the audiovisual benefit. So far, however, inverse effectiveness has not been demonstrated for complex audiovisual speech stimuli. Here we assess whether this multisensory integration effect can also be observed for the recognizability of spoken words. To that end, we presented audiovisual (...) sentences to 18 native-Dutch normal-hearing participants, who had to identify the spoken words from a finite list. Speech-recognition performance was determined for auditory-only, visual-only (lipreading) and auditory-visual conditions. To modulate acoustic task difficulty, we systematically varied the auditory signal-to-noise ratio. In line with a commonly-observed multisensory enhancement on speech recognition, audiovisual words were more easily recognized than auditory-only words (recognition thresholds of -15 dB and -12 dB, respectively). We here show that the difficulty of recognizing a particular word, either acoustically or visually, determines the occurrence of inverse effectiveness in audiovisual word integration. Thus, words that are better heard or recognized through lipreading, benefit less from bimodal presentation. Audiovisual performance at the lowest acoustic signal-to-noise ratios (45%) fell below the visual recognition rates (60%), reflecting an actual deterioration of lipreading in the presence of excessive acoustic noise. This suggests that the brain may adopt a strategy in which attention has to be divided between listening and lipreading. (shrink)

Background Speech understanding may rely not only on auditory, but also on visual information. Non-invasive functional neuroimaging techniques can expose the neural processes underlying the integration of multisensory processes required for speech understanding in humans. Nevertheless, noise (from fMRI) limits the usefulness in auditory experiments, and electromagnetic artefacts caused by electronic implants worn by subjects can severely distort the scans (EEG, fMRI). Therefore, we assessed audio-visual activation of temporal cortex with a silent, optical neuroimaging technique: functional near-infrared spectroscopy (fNIRS). Methods (...) We studied temporal cortical activation as represented by concentration changes of oxy- and deoxy-hemoglobin in four, easy-to-apply fNIRS optical channels of 33 normal-hearing adult subjects and 5 post-lingually deaf cochlear implant (CI) users in response to supra-threshold unisensory auditory and visual, as well as to congruent auditory-visual speech stimuli. Results Activation effects were not visible from single fNIRS channels. However, by discounting physiological noise through reference channel subtraction, auditory, visual and audiovisual speech stimuli evoked concentration changes for all sensory modalities in both cohorts (p<0.001). Auditory stimulation evoked larger concentration changes than visual stimuli (p<0.001). A saturation effect was observed for the audiovisual condition. Conclusions Physiological, systemic noise can be removed from fNIRS signals by reference channel subtraction. The observed multisensory enhancement of an auditory cortical channel can be plausibly described by a simple addition of the auditory and visual signals with saturation. (shrink)

In lieu of an abstract, here is a brief excerpt of the content:482 HISTORY OF PHILOSOPHY G. E. Michalson, Jr. TheHistoricalDimensions ofaRattonalFaith. Washington, D.C.: University Press of America, 1977. Pp. 222. $8.65. The primary intentionof this work is to argue that historical or ecclesiastical religion plays a vital role in Kant's religious thought, because it is necessary to provide a sensible content for the purely formal doctrine of Kant's "moral" religion. But Michalson resists that this strategy cannot succeed, because of (...) the technical requirements of Kant's eplstmology, and that we must ultimately encounter an "impasse" in Kant's thought on history and religion (pp. 77, 134, 169). This is an area of Kant's thought that has not until recently received the attention it deserves. A careful consideration of all the related issued helps one to recognize, from perhaps the most beneficial standpoint, how all the various parts of Kant's philosophical scheme fit together. Michalson quite rightly maintains that we must remain within the epistemological framework Kant has established for the Critical Philosophy. But unfortunately he recognizes only the negative aspects of this framework. What he chooses to call "Kant's principle of human limitations" (mentioned thirtynine times) is the essential element in his interpretation. Secondly, Michalson is unwilling to follow the lead of other commentators (e.g., Michel Despland and Ylrmiahu Yovel) in broadening the context still further in order to take into account the full scope of Kant's philosophical project. These two defects persist throughout Michalson's analysis, and ultimately they prevent any fruitful conclusions. The approach employed, in its most simple form, ~sto point out that historical religion belongs to the phenomenal order and that morality (as the basis for Kant's technical rehgious position) belongs to the noumenal order. Kant's recognition of the need to bridge this gap is dealt with in terms of the "schematism of analogy" (pp. 95, 112-13) mentioned in Religion withinthe Ltmits ofReasonAlone. Michalson provides an interpretation of the schematism m Chapter 3 and concludes that "Kant's Religion is not altogether consistent with certain basic teachings of the critical philosophy" (p. 132). His attempt to deal with this problem carries him into a discussion of teleology and the highest good (Chapter 4), and it is only in this concluding chapter that his various interpretive errors crystallze and produce their Inevitable consequences. Rather than emphasizing the negative aspects of Kant's conception of man, Despland offers Kant's positive perspective on man and his destiny----drawing, for example, on the Anthropologyfrom a PragmaticPoint of View. Employing equally good judgment, Yovel provides an interpretation of the highest good which shows it as the culmination (in the indefinite future) of the concrete process through which man's social, political, educational, and religious development takes place. These perspectives permit the historical dimension (both religious and secular) to be gradually transformed by the imposition of moral designs--as men ~lowly and painfully assume responsibility for directing the blind laws of nature into patterns that serve moral ends. Such commentators help us to see more clearly what Kant was attempting to achieve and how the elements of his total philosophical scheme are to be understood as interconnected. Michalson, on the other hand, has only his impasse to offer us. Because history is phenomenal and religion (as morality) is noumenal, he maintainsthat no bridge is possible between the two realms. But this is simply a failure to recognize Kant's strategy. For Kant is very careful to restrict knowledge (in the strict sense) to the phenomenal order. But he is equally clear in asserting that it is legitimate (indeed, necessary) to postulate those conditions which alone make it possible for us to act in conformity with the moral law. Therefore, we must postulate not only God and immortality but the possibility of a worldly order which conforms both to the laws of nature and to the moral law. And for Kant these postulates have the full strength of rational truths, m that--like the postulates of mathematics -reason cannot reject them. Interpreting Kant's phenomenon-noumenon distinction strictly (but misapplying it), Michalson insists that such a projected ideal state of the world is inconsistent with Kant's epistemological commitment. For such... (shrink)

A careful examination of descartes' works shows that innate ideas are not born with the mind, But are generated by (i.E., Born within) the mind. This is descartes' way of talking about empirical concept formation, As well as what the mind can infer from these concepts. Particular examples are examined to provide the material and formal conditions for identifying innate ideas. Descartes forces the transition from medieval to very modern epistemology.