This book describes a program of research in computable structure theory. The goal is to find definability conditions corresponding to bounds on complexity which persist under isomorphism. The results apply to familiar kinds of structures (groups, fields, vector spaces, linear orderings Boolean algebras, Abelian p-groups, models of arithmetic). There are many interesting results already, but there are also many natural questions still to be answered. The book is self-contained in that it includes necessary background material from recursion theory (ordinal notations, (...) the hyperarithmetical hierarchy) and model theory (infinitary formulas, consistency properties). (shrink)

In their simplest form, hybrid languages are propositional modal languages which can refer to states. They were introduced by Arthur Prior, the inventor of tense logic, and played an important role in his work: because they make reference to specific times possible, they remove the most serious obstacle to developing modal approaches to temporal representation and reasoning. However very little is known about the computational complexity of hybrid temporal logics.In this paper we analyze the complexity of the satisfiability problem of (...) a number of hybrid temporal logics: the basic hybrid language over transitive trees; nominal Until logic; and referential interval logic. We discuss the effects of including nominals, the @ operator, the somewhere modality E, and the difference operator D. Adding nominals to tense logic leads for several frame-classes to an increase in complexity of the satisfiability problem from PSPACE to EXPTIME. On transitive trees, however, the satisfiability problem for this language can be decided in PSPACE. Along the way we make a detour through hybrid propositional dynamic logic: we establish upper bounds for a number of temporal logics by generalizing results due to Passy and Tinchev [29] and De Giacomo [16]. We conclude with some remarks on the relevance of our results to description logic, and draw attention to the utility of the spypoint technique for proving upper and lower bounds. (shrink)

BackgroundResuscitation and treatment of critically ill newborn infants is associated with relatively high mortality, morbidity and cost. Guidelines relating to resuscitation have traditionally focused on the best interests of infants. There are, however, limited resources available in the neonatal intensive care unit, meaning that difficult decisions sometimes need to be made. This study explores the intuitions of lay people regarding resource allocation decisions in the NICU.MethodsThe study design was a cross-sectional quantitative survey, consisting of 20 hypothetical rationing scenarios. There were (...) 119 respondents who entered the questionnaire, and 109 who completed it. The respondents were adult US and Indian participants of the online crowdsourcing platform Mechanical Turk. Respondents were asked to decide which of two infants to treat in a situation of scarce resources. Demographic characteristics, personality traits and political views were recorded. Respondents were also asked to respond to a widely cited thought experiment involving rationing.ResultsThe majority of respondents, in all except one scenario, chose the utilitarian option of directing treatment to the infant with the higher chance of survival, higher life expectancy, less severe disability, and less expensive treatment. As discrepancy between outcomes decreased, however, there was a statistically significant increase in egalitarian responses and decrease in utilitarian responses in scenarios involving chance of survival, life expectancy, and cost of treatment. In the classic ‘lifeboat’ scenario, all but two respondents were utilitarian.ConclusionsThis survey suggests that in situations of scarcity and equal clinical need, non-health professionals support rationing of life-saving treatment based on probability of survival, duration of survival, cost of treatment or quality of life. However, where the difference in prognosis or cost is very small, non-health professionals preferred to give infants an equal chance of receiving treatment. (shrink)

Theories of truth and vagueness are closely connected; in this article, I draw another connection between these areas of research. Gupta and Belnap’s Revision Theory of Truth is converted into an approach to vagueness. I show how revision sequences from a general theory of definitions can be used to understand the nature of vague predicates. The revision sequences show how the meaning of vague predicates are interconnected with each other. The approach is contrasted with the similar supervaluationist approach.

We extend results of Harizanov and Barker. For a relation R on a recursive structure /oA, we give conditions guaranteeing that the image of R in a recursive copy of /oA can be made to have arbitrary ∑α0 degree over Δα0. We give stronger conditions under which the image of R can be made ∑α0 degree as well. The degrees over Δα0 can be replaced by certain more general classes. We also generalize the Friedberg-Muchnik Theorem, giving conditions on a pair (...) of relations R and S under which the images of R and S can be made ∑α0 and independent over Δα0 in a recursive copy of /oA. (shrink)

Let be a recursive structure, and let R be a recursive relation on . Harizanov isolated a syntactical condition which is necessary and sufficient for to have recursive copies in which the image of R is r.e. of arbitrary r.e. degree. We had conjectured that a certain extension of Harizanov's syntactical condition would be necessary and sufficient for to have recursive copies in which the image of R is ∑α0 of arbitrary ∑α0 degree, but this is not the case. Here (...) we give examples illustrating some restrictions on the possible ∑α0 degrees. In these examples, the image of R cannot be ∑α0 of degree d unless d possesses an “α-table”. (shrink)

It is now commonly accepted that N. Goodman's predicate "grue" presents the theory of confirmation of C. G. Hempel (and other such theories) with grave difficulties. The precise nature and status of these "difficulties" has, however, never been made clear. In this paper it is argued that it is very unlikely that "grue" raises any formal difficulties for Hempel and appearances to the contrary are examined, rejected and an explanation of their intuitive appeal offered. However "grue" is shown to raise (...) an informal, "over-arching" difficulty of great magnitude for all theories of confirmation, including Hempel's theory. (shrink)

In this paper I present a range of substructural logics for a conditional connective ↦. This connective was original introduced semantically via restriction on the ternary accessibility relation R for a relevant conditional. I give sound and complete proof systems for a number of variations of this semantic definition. The completeness result in this paper proceeds by step-by-step improvements of models, rather than by the one-step canonical model method. This gradual technique allows for the additional control, lacking in the canonical (...) model method, that is required. (shrink)

Contemporary issues such as euthanasia, surrogate motherhood, organ transplantation and gene therapy, which occupy the minds of ethicists in the industrialized countries are, for the moment, irrelevant in most developing countries. There, the ethics of scarcity, sacrifice, cross-cultural research, as well as the activities of multinational companies, are germane. In this article, only the ethics of scarcity and sacrifice will be discussed. Structural adjustment programmes, designed to solve the economic problems of the developing countries, muddied the waters. The dilemma confronting (...) practitioners in developing countries is how to adhere to the basic principles of medical ethics in an atmosphere of hunger, poverty, war and ever-shrinking and often non-existent resources. Nowhere else in the world is the true meaning of scarcity portrayed as vividly as in the developing countries. Consequently, the doctor's clinical freedom may have to be sacrificed by the introduction of an essential drugs list and practice guidelines. The principle of greater good, while appealing, must be carefully interpreted and applied in the developing countries. Thus, while health promotion and disease prevention must be the primary focus, health planners should avoid pushing prevention at the expense of those currently sick. Health care reform in developing countries must not merely re-echo what is being done in the industrialized countries, but must respond to societal needs and be relevant to the community in question. (shrink)

The popular concept and practice of science as an exclusively objective exercise ignores the study of rich and unavoidable subjective phenomena relating to mind. This article proposes that as a process of generating knowledge from perceptual experiences, science-skill is innate to man, which demands precision and effective management of bias, and relies on faith for communication. It manifests in man along two dimensions, one of precision and the other of need and interest. Two more dimensions influence its practice and communicability. (...) This dimensionality accommodates scientific study of diverse human experiences, including religion and spirituality. Evolution of scientific study of mind requires complementing the existing objective techniques with development of techniques for investigating subjective and intuitive experiences. It would also benefit by borrowing concepts and methodologies from ancient Indian philosophies and spiritual practices. Swami Vivekananda's observations are presented in this connection. (shrink)

In Campbell Soup Co. v. Allstate Insurance Co. ), the United States District Court for the Western District of Michigan, Southern Division, held that a health plan's coordination of benefits clause, covered under the Employee Retirement Income Security Act, does not preempt a similar no-fault automobile insurance clause in the absence of irreconcilable conflict. The court found that ERISA's policy of shielding plans from unanticipated claims could only be furthered when the plan had expressly disavowed such claims. Because the ERISA (...) plan in this case did not specifically subordinate itself to the no-fault policy, the district court found that the no-fault COB clause controlled. However, to escape this ruling, ERISA plans need only redraft their COB clauses specifically to disclaim liability in case of conflict with provisions of no-fault insurance policies. This caveat substantially limits the scope of the court's ruling. (shrink)

In many systems, the tensors used to describe physical properties must acquire their structure from one vector. Knowledge of that fact alone leads to an interesting line of analysis for such systems. The analysis begins with a discussion of the types of dyadics that can be constructed from one vector. Attention is focused on certain exemplary dyadic operators, which, because of their geometrical properties, would appear particularly basic; the algebra of these dyadics is developed in detail. The algebra is then (...) used in a derivation of the expansion of general functions of these dyadics. Several applications of the general expansion are presented: the inverse of a general dyadic operator (when it exists), a general rotation operator that includes strains and reflections, the determinant of a general dyadic operator, and operators, including some new ones, used in constructing Lorentz boosts. Finally, a coordinate-free representation of the Levi-Civita tensor is provided. (shrink)

Coleridge has been seen by some not so much as a poet spoiled by philosophy, but as a philosopher who was also a poet. It could be argued that his major endeavor was an attempt to save the life sciences form the mechanistic interpretation which he saw as the outcome of Lockean "mechanico-corpuscularian" philosophy. This contribution describes that endeavour. It shows its connection to the social circumstances of the time. It discussess its relationship to the poetic sensibility of the "Lake (...) poets" and to the German thought which Coleridge absorbed during and after his sojourn in Gottingen in 1798-99. It describes the nature of his "Theory of Life" as seen not only from the posthumous publication itself, but also from the numerous hints and struggles recorded in his voluminous notebooks, letters and lecture notes. It is concluded that, although never adequately assembled, it forms the only serious attempt to construct a profound alternative to the ultimately mechanistic biology of Charles Darwin and the physiologists of the second half of the century. As such it strongly influenced the young Richard Owen and, as is well known, was eventually overwhelmed by the Darwin-Huxley synthesis of the 1860s. Nevertheless, insofar as Coleridge's concept of life ultimately derived from his ambition to find a way of healing the Cartesian divide, we may wonder whether the recent upsurge in consciousness studies may cause us to look again at his panentheistic ideas and, discarding the obsolete and fanciful metaphysics, recast them into a more acceptable form. (shrink)

This book explores a wide range of philosophical issues in their connection with theism, including views of free will, ethical theories, theories of mind, naturalism, and karma-plus-reincarnation. In this clear and logical guide, C. Stephen Layman takes up eight important philosophical questions about God: Does God exist? Why does God permit evil? Why think God is good? Why is God hidden? What is God's relationship to ethics? Is divine foreknowledge compatible with human free will? Do humans have souls? Does reincarnation (...) provide the best explanation of suffering? Based on more than thirty years of experience in teaching undergraduates and in leading philosophical discussions related to God, Layman has arranged the text to deal with each of these eight questions in one or two chapters apiece. Many philosophical works take up questions about God, but the chapters of this book plunge the reader very quickly into the arguments relevant to each question. Layman presents the arguments cogently and simply, yet without oversimplifying the issues. The book emphasizes strengths and weaknesses of both theism and its metaphysical rivals. Readers will gain a clearer understanding of theism and naturalism, and of their sometimes surprising implications. (shrink)

Thinking aloud is the concurrent verbalization of thoughts while performing a task. The study of thinking-aloud protocols has a long tradition in cognitive psychology, the field of education, and the industrial-organizational context. It has been used rarely in cultural and cross-cultural psychology. This paper will describe thinking aloud as a useful method in cultural and cross-cultural psychology referring to a few studies in general and one study in particular to show the wide applications of this method. Thinking-aloud protocols can be (...) applied for a) improving the validity of cross-cultural surveys, b) process analysis of thoughts and the analysis of changes over time, c) theory development across cultures, d) the study of cultural meaning systems, and e) individual as well as group level analyses allowing hypothesis testing cross-culturally. Limitations of the thinking-aloud method are also discussed. (shrink)