Nucleation and motion of kink pairs on partial dislocations are examined by elasticity theory for materials with a high Peierls stress. Two approaches are used: one considers the change in average stacking-fault energy due to alloying elements and the other considers the change in local SFE due to a nearby solute atom. Both approaches highlight the role of SFE on kink nucleation, propagation and annihilation and both furnish strain rate as a function of stress, temperature and SFE. Model predictions are (...) compared with yield stress data for two systems: firstly, an intermetallic, MoSi 2 , which softens for alloying elements that decrease the SFE and hardens for Re additions that increase the SFE; secondly, a ceramic oxide, MgO-Al 2 O 3 spinel, which softens with increasing addition of excess alumina and at the same time exhibits a decrease in SFE. The average SFE approach agrees qualitatively with the data while quantitative agreement is obtained with the local SFE approach. The possibility is considered that the model applies to other materials, such as TiAl, HfV 2 and Fe 3 Al, which show softening with certain alloying additions. One requirement is that the dislocations are dissociated more than a few atomic distances; otherwise kink nucleation occurs on the perfect dislocation . Hence the model does not apply to materials such as bcc metals which only have a core dissociation. Normal hardening effects of solutes from size and modulus misfits are additive with any softening effects from a decrease in SFE and so may mask the latter, as occurs for W additions to MoSi 2. (shrink)

Surrogate (proxy) decision makers must make research decisions for people with dementia who lack decision-making capacity. Proxies’ decision-making processes are minimally understood. We randomly assigned 82 proxies of AD patients to informed consent for one of three hypothetical protocols with differing levels of risk and benefit. Proxies answered questions about potential benefits of the described research to the patient and society, as well as about whether they would enroll their relative and why or why not. Proxies interested in enrolling their (...) relative cited the potential for direct benefit to their relative, altruism, and trust in researchers. Those declining cited risks, inconvenience, and stage of illness. Proxies weighed numerous factors, incorporating both substituted judgment and best interests standards in their decision-making processes. Although further empirical work is needed to understand the influences on and adequacy of proxies’ decision making regarding research, these findings can help inform policy regarding surrogate consent. (shrink)

Cortical stimulation has been used for brain mapping for over a century, and a standard assumption is that stimulation interferes with task execution due to local effects at the stimulation site. Stimulation can however produce afterdischarges which interfere with functional localization and can lead to unwanted seizures. We previously showed that cognitive effort can terminate these afterdischarges, when termination thus occurs, there are electrocorticography changes throughout the cortex, not just at sites with afterdischarges or sites thought functionally important for the (...) cognitive task used, and thresholds for afterdischarges and functional responses can change among stimulation trials. We here show that afterdischarge termination can occur prior to overt performance of the cognitive tasks used to terminate them. These findings, taken together, demonstrate that task-related brain changes are not limited to one or a group of functional regions or a specific network, and not limited to the time directly surrounding overt task execution. Discrete locations, networks and times importantly underpin clinical behaviors. However, brain activity that is diffuse in location and extended in time also affect task execution and can affect brain mapping. This may in part reflect fluctuating levels of attention, engagement, or motivation during testing. (shrink)

R. S. Peters on Education and Ethics reissues seven titles from Peters' life's work. Taking an interdisciplinary approach, the books are concerned with the philosophy of education and ethics. Topics include moral education and learning, authority and responsibility, psychology and ethical development and ideas on motivation amongst others. The books discuss more traditional theories and philosophical thinkers as well as exploring later ideas in a way which makes the subjects they discuss still relevant today.

One of the greatest of modern philosophers, on a par with his contemporary John Locke, Leibniz was born in Leipzig in 1646, died in Hanover in 1716. He was a leading figure in European intellectual circles, and the founder of the Academy of Berlin. His strange, complex metaphysical system established him as the third of the great 'Rationalists', after Descartes and Spinoza. Along with the 'New System', his most famous philosophical works are the Discourse of Metaphysics and Monadology. He also (...) made important contributions to logic, mathematics, theology, jurisprudence, and history.Gathered here for the first time are all the key texts in a crucial debate in modern philosophy, centred on Leibniz's famous 1695 essay, the `New System of the Nature of Substances and their Communication'. In this classic essay Leibniz introduced to a broad European readership the strikingly original metaphysical ideas he had come to a decade earlier. His 'system' became increasingly famous and drew him into discussion and development of these ideas, both in public and in private, with a variety of thinkers: Simon Foucher; Henri Basbage de Beauval; Francois Lamy; Isaac Jacquelot; the Englishwoman Damaris Masham; Pierre Desmaizeaux; René Joseph de Tournemine; and most notably the great French philosopher and scholar Pierre Bayle. (shrink)

"Williams's masterful translation satisfies (at last!) a long-standing need. There are lots of good translations of Augustine's great work, but until now we have been forced to choose between those that strive to replicate in English something of the majesty and beauty of Augustine's Latin style and those that opt instead to convey the careful precision of his philosophical terminology and argumentation. Finally, Williams has succeeded in capturing both sides of Augustine's mind in a richly evocative, impeccably reliable, elegantly readable (...) presentation of one of the most impressive achievements in Western thought--Augustine's Confessions." --Scott MacDonald, Professor of Philosophy and Norma K. Regan Professor in Christian Studies, Cornell University. (shrink)

Shaḥrūr, Muḥammad; Islamic philosophy; Qurʼan; hermeneutics; criticism, interpretation, etc.

The book offers an introduction to the moral concepts and value of health care. It is written by a moral philosopher, a doctor and a nurse and contains questions, cases and exercises which are suitable for medical, nursing and all students and commentators on health care. Moral dilemmas include consent, confidentiality, the giving or withholding of information, and the economics of health care. The issues of artificial reproduction, terminal care and the research and testing of drugs are addressed.

The main thesis of this book is that Wittgenstein’s early philosophy is an exemplification of Newtonian physics, whereas the later philosophy exemplifies contemporary, relativistic physics. The reader may recall Wittgenstein’s insistence, during both major periods of his thought, upon the separation of philosophy from science. However, Bolton’s unstated premise is that Wittgenstein’s thought was unconsciously determined by two different conceptions of physics. Whatever one may think of this, it leaves a question unanswered. Since both periods of Wittgenstein’s thought follow the (...) development of relativistic physics, why was he initially influenced by Newtonian physics or its expression in modern philosophy? Was this a contingent error of the youthful Wittgenstein, or an expression of historical inevitability? We find no discussion of this difficult problem in Bolton’s book. Instead, he claims, and to some extent shows, that Wittgenstein, in the Tractatus, crystallizes the axioms of modern philosophy, which is essentially Newtonian. At the historical level, this thesis is either wrong or uninformative. It is wrong because not all of modern philosophy can be explained on the basis of the peculiarities of modern or Newtonian physics. It is uninformative because to the extent that all modern philosophers took Newtonian physics for granted, the latter cannot account for the sharp differences between, say, John Locke and Hegel. Nevertheless, Bolton provides interesting and plausible reasons for regarding the Tractatus as an expression of that aspect of modern philosophy which may profitably be called "Newtonian." He fails to convince at least one reader that the repudiation of the Tractatus is a repudiation of modern philosophy for anyone other than Wittgenstein and his followers. On the other hand, once we discount, or even disregard, Bolton’s historical thesis, the more traditional virtues of his book come sharply into focus. Having recently reviewed the 686 page commentary by Baker and Hacker on the first third of the Investigations, as well as Wright’s 481 page essay on Wittgenstein’s philosophy of mathematics, the author of this note is in a good position to appreciate the economy and lucidity of Bolton’s summary analysis of the main points in the Tractatus. As an example of my disagreement with Bolton’s interpretation, I begin with a brief citation from p. 86. (shrink)

First published in 1981, this collection of essays was taken from Peters' larger work, Psychology and Ethical Development in order to provide a more focused volume on moral education for students. Peters' background in both psychology and philosophy makes the work distinctive, which is evident from the first two essays alone: 'Freud's theory of Moral Development in Relation to that of Piaget' and 'Moral Education and the Psychology of Character'. He also displays balance in his acceptance that reason and feeling (...) are both of great importance where the subject of moral education is concerned. Although written some time ago, the book discusses issues which are still of considerable interest and importance today. (shrink)

An early work of Marcel's, mainly expository, written because he held that a contemporary philosopher cannot reflect on questions of time and eternity and of the nature of the individual without close scrutiny of Royce's solution. Marcel develops Royce's conception of absolute idealism from the analysis of certain perennial problems of epistemology. The problematic approach lends cogency to a lucid exposition.--R. G. S.

PREFACE The first three of these lectures, or rather an abbreviated version of them, were first given as the Lindsay Memorial Lectures at the University of ...

The Fourth Volume of Livy's text in the Oxford Series is in the Press, and it is time to fulfil a duty which for some years I have owed to the study of Livy—namely, to provide students with fuller information about the character of this important manuscript than could be included in the Praefatio to the third or fourth volume.

Critiquing many areas of medical practice and research whilst making constructive suggestions about medical education, this book extends the scope of medical ethics beyond sole concern with regulation. Illustrating some humanistic ways of understanding patients, this volume explores the connections between medical ethics, healthcare and subjects, such as philosophy, literature, creative writing and medical history and how they can affect the attitudes of doctors towards patients and the perceptions of medicine, health and disease which have become part of contemporary culture. (...) The authors examine a range of ideas in medical practice and research, including: the idea that patient status or the doctor/patient relationship can be understood via quantitative scales the illusion fostered by medical ethics that doctors, unlike those in other professions, are uniquely beneficent and indeed altruistic. An excellent text for undergraduate and postgraduate students of law, medical ethics and medical healthcare law, Bioethics and the Humanities shows the real ethical achievements, problems and half-truths of contemporary medicine. (shrink)

Azarya Polikarov was born in Sofia on October 9, 1921. Through the many stages of politics, economy, and culture in Bulgaria, he maintained his rational humanity and scientific curiosity. He has been a splendid teacher and an accomplished critical philosopher exploring the conceptual and historical vicis situdes of physics in modern times and also the science policies that favor or threaten human life in these decades. Equally and easily at home both within the Eastern and Central European countries and within (...) the Western world. Polikarov is known as a collaborating genial colleague, a working scholar. not at all a visiting academic tourist. He understands the philosophy of science from within, in all its developments, from the classical beginnings through the great ages of Galilean, Newtonian. Maxwellian science. to the times of the stunning discoveries and imaginative theories of his beloved Einstein and Bohr of the twentieth century. Moreover, his understanding has come along with a deep knowledge of the scientific topics in themselves. Looking at our Appendix listing his principal publications, we see that Polikarov's public research career, after years of science teaching and popular science writing, began in the fifties in Bulgarian, Russian and German journals. (shrink)