A theory of the joint measurement of quantum mechanical observables is generalized in order to make it applicable to the measurement of the local observables of field theory. Subsequently, the property of local commutativity, which is usually introduced as a postulate, is derived by means of the theory of measurement from a requirement of mutual nondisturbance, which, for local observables performed at a spacelike distance from each other, is interpreted as a requirement of macrocausality. Alternative attempts at establishing a deductive (...) relationship between relativistic causality and local commutativity are reviewed, but found wanting, either because of the assumption of an unwarranted objectivity of the object system (algebraic approach) or because of the use of a projection postulate (operational approach). Finally, the quantum mechanical nonobjectivity is related to certain features of nonlocality which are present in the formalism of quantum mechanics. (shrink)

A construction is described of a cartesian closed category A with exactly two elements out of a C-monoid such that can be recovered from A without reference to the construction.

Rid and Wendler propose the development of a Patient Preference Predictor (PPP), an actuarial model for predicting incapacitated patient’s life-sustaining treatment preferences across a wide range of end-of-life scenarios. An actuarial approach to end-of-life decision making has enormous potential, but transferring the logic of actuarial prediction to end-of-life decision making raises several conceptual complexities and logistical problems that need further consideration. Actuarial models have proven effective in targeted prediction tasks, but no evidence supports their effectiveness in the kind of broad (...) spectrum prediction task that is the proposed goal of the PPP. We argue that a more focused approach, targeting specific medical conditions and generating treatment predictions based on the preferences of individuals with actual disease experience, is both more firmly grounded in past research and is a more prudent initial strategy for exploring the efficacy of actuarial prediction in end-of-life decision making. (shrink)

Doctors are regularly confronted with requests for sterilisation of mentally handicapped people who cannot give consent for themselves. They ought to act in a medical vacuum because there doesn't exist a consensus about a model for decision making on this matter. In this article a model for decision making is proposed, based on a review of the literature and our own research data. We have attempted to select and classify certain factors which could enable us to arrive at an ethically (...) justifiable method of making a medical decision. In doing so we distinguish two major criteria: heredity and parenting competence, and six minor criteria: conception risk, IQ, age, personality, medical aspects and prognosis and finally support and guidance for the mentally handicapped person. The major criteria give rise to a "situation of necessity". In this situation the physician is confronted with a conflict of values and interests. The minor criteria are of an entirely different ethical order. They can only be considered once the major criteria have created a "situation of necessity". Ultimately it comes down to deciding whether the benefits of sterilisation outweigh the drawbacks and whether the means are appropriate to the end, where efficient contraception is the end and irreversible sterilisation is the means. (shrink)

From early sage philosophers to Leopold Senghor of Senegal and Steve Biko of South Africa, African thinking has challenged the way we think. As we enter a new millenium, the perspectives provided in this volume offer wise and refreshing alternatives to problems of self and society, culture, aesthetics, metaphysics and religion. Out of Africa always something new, and in these pages contemporary problems of cross-cultural cognition and post-coloniality are not only addressed, but also enacted. The reader witnesses the collision and (...) the coalescence of cultures in the writings of philosophers from Africa. (shrink)

It is demonstrated on the basis of the Dirac equation that quarks cannot be confined by a vector gluon potential of the form(r/r 0)a or[ln(r/r 0]a, a>0, if the quark-gluon interaction conserves parity. In order to confine quarks with the parity-conserving interaction, the effective gluon potential must be a pseudovector or a scalar. These are shown in a simple Yang-Mills field with theSU(2) group.

Harris levels two main criticisms against our original defence of QALYs (Quality Adjusted Life Years). First, he rejects the assumption implicit in the QALY approach that not all lives are of equal value. Second, he rejects our appeal to Rawls's veil of ignorance test in support of the QALY method. In the present article we defend QALYs against Harris's criticisms. We argue that some of the conclusions Harris draws from our view that resources should be allocated on the basis of (...) potential improvements in quality of life and quantity of life are erroneous, and that others lack the moral implications Harris claims for them. On the other hand, we defend our claim that a rational egoist, behind a veil of ignorance, could consistently choose to allocate life-saving resources in accordance with the QALY method, despite Harris's claim that a rational egoist would allocate randomly if there is no better than a 50% chance of being the recipient. (shrink)

This book addresses the problem of how to make democratically-legitimate public policy on issues of contentious bioethical debate. It focuses on ethical contests about research and their legitimate resolution, while addressing questions of political legitimacy. How should states make public policy on issues where there is ethical disagreement, not only about appropriate outcomes, but even what values are at stake? What constitutes justified, democratic policy in such conflicted domains? Case studies from Canada and Australia demonstrate that two countries sharing historical (...) and institutional characteristics can reach different policy responses. This book is of interest to policymakers, bioethicists, and philosophers, and will deepen our understanding of the interactions between large-scale socio-political forces and detailed policy problems in bioethics. (shrink)

For the successful achievement of evidence-based practice, clinicians, managers and purchasers need evidence on whether a particular intervention works and ways to judge the appropriateness of the outcome criteria and measures used. Guidance is needed on what outcome measure to use, especially within routine clinical care settings. Beginning with a re-clarification of the difference between a health status and an outcome measure, the paper presents an evaluative checklist for use by clinical audit and research staff to review outcome measures for (...) use in routine care settings. Central features include the user-centredness of the measure, its psychometric properties, feasibility of use and utility. The applicability of the checklist is illustrated for outcome measurement in diabetes and stroke care. A modified form of the checklist is proposed for use by the busy clinician as an aid to the critical review of research papers within the context of evidence-based practice and to aid health care practitioners' choice of which outcome measure(s) to use within routine clinical care. (shrink)