A continuoxis t- norm is a continuous map * from [0, 1]² into [0,1] such that is a commutative totally ordered monoid. Since the natural ordering on [0,1] is a complete lattice ordering, each continuous t-norm induces naturally a residuation → and becomes a commutative naturally ordered residuated monoid, also called a hoop. The variety of basic hoops is precisely the variety generated by all algebras, where * is a continuous t-norm. In this paper we investigate the structure of the (...) variety of basic hoops and some of its subvarieties. In particular we provide a complete description of the finite subdirectly irreducible basic hoops, and we show that the variety of basic hoops is generated as a quasivariety by its finite algebras. We extend these results to Hájek's BL-algebras, and we give an alternative proof of the fact that the variety of BL-algebras is generated by all algebras arising from continuous t-norms on [ 0,1] and their residua. The last part of the paper is devoted to the investigation of the subreducts of BL- algebras, of Gödel algebras and of product algebras. (shrink)

Psychological research has shown that cognitive illusions, of which visual illusions are just a special case, are systematic and pervasive, raising epistemological questions about how error in all forms of research can be identified and eliminated. The quantitative sciences make use of statistical techniques for this purpose, but it is not clear what the qualitative equivalent is, particularly in view of widespread scepticism about validity and objectivity. I argue that, in the light of cognitive psychology, the ‘error question’ cannot be (...) dismissed as a positivist obsession, and that the concepts of truth and objectivity are unavoidable. However, they constitute only a ‘minimal realism’, which does not necessarily bring a commitment to ‘absolute’ truth, certainty, correspondence, causation, reductionism, or universal laws in its wake. The assumption that it does reflects a misreading of positivism and, ironically, precipitates a ‘crisis of legitimation and representation’, as described by constructivist authors. (shrink)

The issue of wrongful disability arises when parents face the choice whether to produce a child whose life will be unavoidably flawed by a serious disease or disorder (Down syndrome, for example, or Huntington’s disease) yet clearly worth living. The authors of From Chance to Choice claim, with certain restrictions, that the choice to produce such a child is morally wrong. They then argue that an intuitive moral approach––a “person-affecting” approach that pins wrongdoing to the harming of some existing or (...) future person––cannot account for that wrong since the choice to produce such a child cannot, under the logic of the nonidentity problem, harm that child. The authors propose that we supplement the person-affecting approach with an “impersonal” principle that takes the form of their well-known principle N. In this paper, I argue that the authors are mistaken to suppose that a plausibly articulated person-affecting approach cannot account for the wrong of wrongful disability. We can retain an intuitive, comparative, “worse for” account of harm and still identify serious harms imposed by the choice of wrongful disability. In particular, I argue that harm, both to the impaired child and to others, comes not in the form of that procreative choice’s procreative effect but rather in the form of its many distributive effects. I also argue that the rare, residual case in which a person-affecting approach would approve of the choice of wrongful disability does not function as a counterexample to that approach. As a separate matter, I address legal claims for wrongful disability, which are closely akin to claims for wrongful life. The legal claim is brought by the impaired child, not against the parents, but rather against health care providers whose negligent failure to diagnose or inform parents of an increased risk of a genetic or congenital impairment results in the birth of the impaired child. The authors’ treatment of the moral wrong that is done as impersonal in nature suggests that courts are correct to dismiss any such claim. Once we identify harm, however, the person-affecting approach can identify a clear foundation in the law for the wrongful disability claim. (shrink)

R. K. Elliott once commended R. S. Peters' work in philosophy of education for being an authentic expression of the self. Many philosophers, probably including Peters, might see this more as a weakness. In an attempt to resolve this difference various kinds of continuity between philosopher and philosophy are explored. These point to an ideal of a two-way, and ultimately ‘organic’, relationship whereby the philosophy expresses the self and the self is formed by the philosophy. Ways of teaching to favour (...) the development of such authenticity in novice philosophers are discussed. (shrink)

The framework of Findlay & Walker's target article provides a first attempt to model the saccadic system at all levels. Their scheme is based on two main principles. These are “parallel processing of saccade timing and metrics” and “competitive inhibition through winner-take-all strategies.” In our opinion, however, both concepts are in their strictest sense at odds with the current knowledge of the saccadic system, and need to be refined to make the scheme more relevant.

Contour adaptation is a recently described paradigm that renders otherwise salient visual stimuli temporarily perceptually invisible. Here we investigate whether this illusion can be exploited to study visual awareness. We found that CA can induce seconds of sustained invisibility following similarly long periods of uninterrupted adaptation. Furthermore, even fragmented adaptors are capable of producing CA, with the strength of CA increasing monotonically as the adaptors encompass a greater fraction of the stimulus outline. However, different types of adaptor patterns, such as (...) distinctive shapes or illusory contours, produce equivalent levels of CA suggesting that the main determinants of CA are low-level stimulus characteristics, with minimal modulation by higher-order visual processes. Taken together, our results indicate that CA has desirable properties for studying visual awareness, including the production of prolonged periods of perceptual dissociation from stimulation as well as parametric dependencies of that dissociation on a host of stimulus parameters. (shrink)

The classical two-body system with Lorentz-invariant Coulomb work function V = -k/ρ is solved in 3+1 dimensions using the manifestly covariant Hamiltonian mechanics of Stückelberg. Particular solutions for the reduced motion are obtained which correspond to bound attractive, unbound attractive, and repulsive scattering motion. A lack of perihelion precession is found in the bound attractive orbit, and the semiclassical hydrogen spectrum subsequently contains no fine structure corrections. It is argued that this prediction is indicative of the correct classical special relativistic (...) two-body theory. (shrink)

Review of Tibebe Eshete, Evangelical Movement in Ethiopia: Resistance and Resilience (Waco Texas: Baylor University Press, 2009), xiii + 480 pp.

One of the most dramatic advances in the physical sciences during the nineteenth century was the emergence of spectroscopy. It rapidly became an invaluable experimental technique for chemists and astronomers, while for physicists it opened a window upon the world of sub-atomic phenomena. Sir John Herschel played an important part, the value of which has sometimes been underestimated, in the early development of spectroscopy. This paper examines his contribution to the subject during the period 1819–61 in the light of his (...) publications and of certain manuscript material preserved in the Royal Society's Library. Herschel corresponded with most of the scientists who did important work in spectroscopy during his lifetime, and he expressed definite opinions on most of the practical and theoretical problems that arose in it; however, the present study cannot pretend to offer a complete discussion of all aspects of the early history of spectroscopy. (shrink)

The vast majority of contributions to the literature on spirituality in nursing make extravagant claims about transcendence, eternity, the numinous, higher powers, higher levels of existence, invisible forces, cosmic unity, the essence of humanity, or other supernatural concepts. Typically, these assertions are made without the support of argument or evidence; and, as a consequence, alternative ways of theorizing ‘spirituality’ have been closed off, while the lack of consistent scholarship has turned the topic into a metaphysical backwater. In this paper, I (...) adopt a different premise, rejecting unsupported claims, and surveying the ‘spirituality’ terrain from a naturalistic and reductionist perspective. I argue that, if we rid ourselves of non‐naturalistic assumptions, we will discover theoretical and clinical resources in health psychology, social psychology, neuropsychology, and pharmacopsychology – resources which confirm that it is possible to conceptualize the study of existential concerns, and how health professionals might respond to them, in a properly scientific manner. In order to illustrate the potential usefulness of these resources, I will take palliative care as an example. (shrink)

Recognized in his day as a man of letters equaling Rousseau and Voltaire in France and rivaling Samuel Johnson, David Hume passed from favor in the Victorian age--his work, it seemed, did not pursue Truth but rather indulged in popularization. Although Hume is once more considered as one of the greatest British philosophers, scholars now tend to focus on his thought rather than his writing. To round out our understanding of Hume, M. A. Box in this book charts the interrelated (...) development of Hume's literary ambitions, theories of style, and compositional practice from his Treatise in 1739 through the Enquiries. In so doing, Box makes the case for Hume's career-long concern with the presentational modes of reaching an audience for his philosophical writings. Hume reacted to the popular failure of his masterpiece, A Treatise of Human Nature, Box suggests, by self-consciously exploring strategies in his subsequent works for agreeably bringing his readership to participate in the act of philosophizing. Combining a sensitive grasp of the ways Restoration period and eighteenth-century writers conceived the relations between rhetoric and philosophy with sound readings of particular texts, Box shows how Hume's literary concerns went beyond matters of style to involve persona, structure, and doctrine. While this book helps explain long-standing ambiguities surrounding Hume, especially by pointing out the tension between his created persona and his own voice, it also serves as an excellent introduction to his philosophy. (shrink)