A sequent root-first proof-search procedure for intuitionistic propositional logic is presented. The procedure is obtained from modified intuitionistic multi-succedent and classical sequent calculi, making use of Glivenko’s Theorem. We prove that a sequent is derivable in a standard intuitionistic multi-succedent calculus if and only if the corresponding prefixed-sequent is derivable in the procedure.

The cut-free Gentzen-type sequent calculus LLK for the logic of likelihood is introduced in the paper. It is proved that the calculus is sound and complete for LL. Using the introduced calculus LLK, a decision procedure for LL is presented.

While in principle probabilistic logics might be applied to solve a range of problems, in practice they are rarely applied at present. This is perhaps because they seem disparate, complicated, and computationally intractable. However, we shall argue in this programmatic paper that several approaches to probabilistic logic into a simple unifying framework: logically complex evidence can be used to associate probability intervals or probabilities with sentences.

A Leibniz class is a class of logics closed under the formation of term-equivalent logics, compatible expansions, and non-indexed products of sets of logics. We study the complete lattice of all Leibniz classes, called the Leibniz hierarchy. In particular, it is proved that the classes of truth-equational and assertional logics are meet-prime in the Leibniz hierarchy, while the classes of protoalgebraic and equivalential logics are meet-reducible. However, the last two classes are shown to be determined by Leibniz conditions consisting of (...) meet-prime logics only. (shrink)

In this review of the Korean cloning scandal involving Woo-Suk Hwang, the nature of the disaster is documented and reasons why it occurred are suggested. The general problems it raises for scientific research are highlighted and six possible ways of improving practice are offered in the light of this case: better education of science students; independent monitoring and validation; guidelines for tissue donation for research; fostering of debate about ethically contentious research in science journals; development of an international code of (...) ethical research practice; fostering of public involvement in ethical review and debate through the web. (shrink)

SummaryThis article argues that Archibald Campbell's Necessity of Revelation can be viewed as the first application of the ‘science of human nature’, a characteristic branch of the Scottish Enlightenment, to the study of religious belief. Adopting Baconian and Newtonian methodological principles, Campbell set hypotheses, collected historical data, and inferred conclusions about the capabilities of human nature to come to fundamental religious ideas without the aid of revelation. He did so not only to reject the ‘deist’ position on the powers of (...) unassisted human reason, associated with Matthew Tindal's Christianity as Old as the Creation, but also to refute Campbell's conservative critics within the Church of Scotland who had earlier tried him for heresy. Campbell's example is that of a university professor using the experimental study of religion to defeat both radical freethinking and Calvinist orthodoxy. His work is another instance of the complicated relationship between science and religion within eighteenth-century Scotland. (shrink)

Working memory--the ability to keep important information in mind while comprehending, thinking, and acting--varies considerably from person to person and changes dramatically during each person's life. Understanding such individual and developmental differences is crucial because working memory is a major contributor to general intellectual functioning. This volume offers a state-of-the-art, integrative, and comprehensive approach to understanding variation in working memory by presenting explicit, detailed comparisons of the leading theories. It incorporates views from the different research groups that operate on each (...) side of the Atlantic, and covers working-memory research on a wide variety of populations, including healthy adults, children with and without learning difficulties, older adults, and adults and children with neurological disorders. A particular strength of this volume is that each research group explicitly addresses the same set of theoretical questions, from the perspective of both their own theoretical and experimental work and from the perspective of relevant alternative approaches. Through these questions, each research group considers their overarching theory of working memory, specifies the critical sources of working memory variation according to their theory, reflects on the compatibility of their approach with other approaches, and assesses their contribution to general working memory theory. This shared focus across chapters unifies the volume and highlights the similarities and differences among the various theories. Each chapter includes both a summary of research positions and a detailed discussion of each position. Variation in Working Memory achieves coherence across its chapters, while presenting the entire range of current theoretical and experimental approaches to variation in working memory. (shrink)

Implicit processes almost certainly preceded explicit processes in our evolutionary history, so they are likely to be more resistant to disruption according to the principles of evolutionary biology [Reber, A. S. . The cognitive unconscious: An evolutionary perspective. Consciousness and Cognition, 1, 93–133.]. Previous work . Knowledge, nerves and know-how: The role of explicit versus implicit knowledge in the breakdown of a complex motor skill under pressure. British Journal of Psychology, 83, 343–358.]) has shown that implicitly learned motor skills remain (...) stable under psychological pressure and concurrent cognitive demands, and recently [Poolton, J. M., Masters, R. S. W., & Maxwell, J. P. . Passing thoughts on the evolutionary stability of implicit motor behaviour: Performance retention under physiological fatigue. Consciousness and Cognition, 16, 456–468.] showed that they also remain stable under conditions of anaerobic fatigue that would have significantly challenged the survival skills of our ancestors. Here we examine the stability of an implicitly learned motor skill under fatigue conditions that primarily tax a different physiological system , but which have equally strong evolutionary connotations. Participants acquired a throwing task by means of an errorless learning method or an errorful method. Motor performance in the errorless condition, but not the errorful condition, remained stable following an exhaustive VO2 max. running test. Our findings replicate and extend the work of Poolton et al., providing further support for Reber’s evolutionary distinction between implicit and explicit processes. (shrink)

The international disparities in health and health-care provision comprise the gravest problem of medical ethics. The implications are explored of three theories of justice: an expanded version of Rawlsian contractarianism, Nozick's historical account, and a consequentialism which prioritizes the satisfaction of basic needs. The second too little satisfies medical needs to be cogent. The third is found to incorporate the strengths of the others, and to uphold fair rules and practices. Like the first, it also involves obligations transcending those to (...) an agent's relations and fellow-citizens. These conclusions are applied to international health-care provision, which they would transform. (shrink)

Many social scientists and philosophers have counted themselves moral relativists in some sense or other. We cannot deal with all the various views which are properly called forms of “moral relativism”; so I propose to explain a form of moral relativism which seems to me an interesting, and somewhat plausible theory. This theory comprises the following three affirmations: The basic moral principles of different individuals or groups sometimes are, or can be, in some important sense conflicting. When there is such (...) fundamental conflict of basic principles or standards, there is either always, or at least sometimes, no way to show that one view is better justified even in the presence of ideally complete factual information; in that sense the principles are equally justified or “valid.” But there is a sense in which a particular moral belief may be mistaken or unjustified, if it is a misapplication of the basic principles of the individual or group, e.g., if the basic principles plus statements of known or knowable facts entail a moral proposition incompatible with it. As stated, moral relativism could be true even though in fact, accidentally, all individuals agree in their basic moral principles. (shrink)

The famous 1893 Chicago World’s Fair celebrated the dawn of corporate capitalism and a new Machine Age with an exhibit of the world’s largest engine. Yet the noise was so great, visitors ran out of the Machinery Hall to retreat to the peace and quiet of the Japanese pavilion’s Buddhist temples and lotus ponds. Thus began over a century of the West’s turn toward an Asian aesthetic as an antidote to modern technology. From the turn-of-the-century Columbian Exhibition to the latest (...) Zen-inspired designs of Apple, Inc., R. John Williams charts the history of our embrace of Eastern ideals of beauty to counter our fear of the rise of modern technological systems. In a dazzling work of synthesis, Williams examines Asian influences on book design and department store marketing, the commercial fiction of Jack London, the poetic technique of Ezra Pound, the popularity of Charlie Chan movies, the architecture of Frank Lloyd Wright, and the design of the latest high-tech gadgets. Williams demonstrates how, rather than retreating from modernity, writers, artists, and inventors turned to traditional Eastern technê as a therapeutic means of living with—but never abandoning—Western technology. (shrink)

A conference celebrating the tercentenary of the publication of Leibniz’s Nouveau système will be held at the University of York, England, under the auspices of the Leibniz Gesellschaft of Hannover, and in collaboration with the British Society for the History of Philosophy, the Leibniz Society of North America, and the Lessico Intellettuale Europeo in Rome. Speakers will include R. M. Adams, S. Brown, G. Hartz, A. Lamarra, G. M. Ross, M. Mugnai, R. Palaia, G.H.R. Parkinson, P. Phemister, H. Poser, D. (...) Rutherford, C. Wilson. For further details contact Roger Woolhouse, Department of Philosophy, University of York, England Y01 5DD. (shrink)

Wnts are a recently described family of secreted glycoproteins related to the Drosophila segment polarity gene, wingless, and to the proto‐oncogene, int‐1. Wnts are thought to function as developmental modulators, with signalling distances of only a few cell diameters. In Xenopus, at least six Wnts, including Xwnts‐1, ‐3A, and ‐4, are expressed initially in the developing central nervous system, with some regions expressing multiple Xwnts. Xwnt‐8 is expressed by mid‐blastula stage, in ventral and lateral mesoderm. Xwnt‐5A mRNAs are stored in (...) the egg, and later are expressed throughout the embryo in both ectoderm and mesoderm, but with a pronounced enrichment in the head and tail. Recent studies in Xenopus have pursued the diverse roles of Xwnts in early development, the mechanisms by which Xwnts signal information between cells, and the cell physiological responses to Xwnt signals. (shrink)