ABSTRACTDiffraction gratings are famously associated with Henry Rowland of Johns Hopkins University but there were precursors. Although gratings were first made and used in Europe, reliable machines for ruling gratings were developed in the USA, and two men, Lewis Rutherfurd and William Rogers, tackled the problem before Rowland. Rutherfurd, a wealthy independent astronomer, designed and built the first screw-operated engine for ruling diffraction gratings, the fore-runner of almost all subsequent ruling engines. With it he and his assistant D. C. (...) class='Hi'>Chapman ruled many gratings which he generously distributed to practising scientists, thereby materially advancing the science of spectroscopy. Rogers was a Harvard astronomer who developed an interest in the ruling of fine lines on glass that led him to construct a ruling engine with which he investigated the causes of the errors in the rulings he had examined. He continued to seek improvements with a second engine designed for ruling diffraction gratings. He ceased developing this engine when Rowland’s excellent gratings began to be available, concentrating instead on related problems to which he could apply the knowledge and skills he had gained, but his investigations assisted Rowland and other later ruling engine builders. This paper brings together what is known about the ruling engines of Rutherfurd and Rogers, their development, the gratings they produced, their quality and the work that was done with them, and assesses and compares their achievements and the impacts of the work of these two men. (shrink)
The poetry and journalistic essays of Katherine Tillman often appeared in publications sponsored by the American Methodist church. Collected together for the first time, her works speak to the struggles and triumphs of African-American women.
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. The first volume covers the beginnings of a career that is ground-breaking from the outset. Inspired by courses given by Dirac and Bondi, much of the early (...) published work involves linking general relativity with tensor systems. Among his early works is the seminal 1955 paper, 'A Generalized Inverse for Matrices', his previously unpublished PhD and St John's College Fellowship theses, and from 1967, his Adam's Prize-winning essay on the structure of space-time. Add to this his 1965 paper, 'Gravitational collapse and space-time singularities', and the 1967 paper that introduced a remarkable new theory, 'Twistor algebra', and this becomes a truly stellar procession of works on mathematics and cosmology. (shrink)
Professor Sir Roger Penrose is one of the truly original thinkers of our time. He has made several remarkable contributions to science, from quantum physics and theories of human consciousness to relativity theory and observations on the structure of the universe. Unusually for a scientist, some of his ideas have crossed over into the public arena. Now his work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for (...) the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Many important realizations concerning twistor theory occurred during the short period of this third volume, providing a new perspective on the way that mathematical features of the (...) complex geometry of twistor theory relate to actual physical fields. Following on from the nonlinear graviton construction, a twistor construction was found for (anti-)self-dual electromagnetism allowing the general (anti-)self-dual Yang-Mills field to be obtained. It became clear that some features of twistor contour integrals could be understood in terms of holomorphic sheaf cohomology. During this period, the Oxford research group founded the informal publication, Twistor Newsletter. This volume also contains the influential Weyl curvature hypothesis and new forms of Penrose tiles. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Among the new developments that occurred during this period was the introduction of a particular notion of 'quasi-local mass-momentum and angular momentum', the topic of Penrose's Royal (...) Society paper. Many encouraging results were initially obtained but, later, difficulties began to emerge and remain today. Also, an extensive paper (with Eastwood and Wells) gives a thorough account of the relation between twistor cohomology and massless fields. This volume witnesses Penrose's increasing conviction that the puzzling issue of quantum measurement could only be resolved by the appropriate unification of quantum mechanics with general relativity, where that union must involve an actual change in the rules of quantum mechanics as well as in space-time structure. Penrose's first incursions into a possible relation between consciousness and quantum state reduction are also covered here. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Publication of The Emperor's New Mind (OUP 1989) had caused considerable debate and Penrose's responses are included in this volume. Arising from this came the idea that (...) large-scale quantum coherence might exist within the conscious brain, and actual conscious experience would be associated with a reduction of the quantum state. Within this collection, Penrose also proposes that a twistor might usefully be regarded as a source (or 'charge') for a massless field of spin 3/2, suggesting that the twistor space for a Ricci-flat space-time might actually be the space of such possible sources. Towards the end of the volume, Penrose begins to develop a quite different approach to incorporating full general relativity into twistor theory. This period also sees the origin of the Diósi-Penrose proposal. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. This sixth volume describes an actual experiment to measure the length of time that a quantum superposition might last (developing the Diósi-Penrose proposal). It also discusses the (...) significant progress made in relation to incorporating the 'googly' information for a gravitational field into the structure of a curved twistor space. Penrose also covers such things as the geometry of light rays in relation to twistor-space structures, the utility of complex numbers in drawing three-dimensional shapes, and the geometrical representation of different types of musical scales. The turn of the millennium was also an opportunity to reflect on progress in many areas up until that point. (shrink)
Professor Sir Roger Penrose's work, spanning fifty years of science, with over five thousand pages and more than three hundred papers, has been collected together for the first time and arranged chronologically over six volumes, each with an introduction from the author. Where relevant, individual papers also come with specific introductions or notes. Developing ideas sketched in the first volume, twistor theory is now applied to genuine issues of physics, and there are the beginnings of twistor diagram theory (an (...) analogue of Feynman Diagrams). This collection includes joint papers with Stephen Hawking, and uncovers certain properties of black holes. The idea of cosmic censorship is also first proposed. Along completely different lines, the first methods of aperiodic tiling for the Euclidean plane that come to be known as Penrose tiles are described. This volume also contains Penrose's three prize-winning essays for the Gravity Foundation (two second places with both Ezra Newman and Steven Hawking, and a solo first place for 'The Non-linear graviton'). (shrink)
Roger North's The Musicall Grammarian 1728 is a treatise on musical eloquence in all its branches. Of its five parts, I and II, on the orthoepy, orthography and syntax of music, constitute a grammar; III and IV, on the arts of invention and communication, form a rhetoric; and V, on etymology, consists of a history. Two substantial chapters of commentary introduce the text, which is edited here for the first time in its entirety: Jamie Kassler places his treatise within (...) the broader context not only of North's musical and non-musical writings but also their relation to the intellectual ferment of the seventeenth and eighteenth centuries and Mary Chan describes physical and textual aspects of the treatise as evidence for North's processes of thinking about musical thinking. (shrink)
The Inexact and Separate Science of Economics represents the most ambitious attempt to provide a systematic account of economic methodology since the first edition of Blaug's The Methodology of Economics. As such, it has been the subject of extensive critical commentary. For all the attention it has received, however, some important aspects of the book's thesis have not been developed properly. Two important ones are what might be called, following the terminology used in the experimental economics literature, the ‘framing effect’ (...) of Hausman's definition of economics, and the significance of Hausman's claim that economists are committed to developing economics as a ‘separate’ science. To understand these points it is important to make explicit the position from which Hausman approaches the philosophy of science. (shrink)
In his bestselling work of popular science, Sir Roger Penrose takes us on a fascinating roller-coaster ride through the basic principles of physics, cosmology, mathematics, and philosophy to show that human thinking can never be emulated by a machine.
In Reasons and the Good Roger Crisp answers some of the oldest questions in moral philosophy. Fundamental to ethics, he claims, is the idea of ultimate reasons for action; and he argues controversially that these reasons do not depend on moral concepts. He investigates the nature of reasons themselves, and how we come to know them. He defends a hedonistic theory of well-being and an account of practical reason according to which we can give some, though not overriding, priority (...) to our own good over that of others. (shrink)
This paper argues for two theses: that degrees of belief are context sensitive; that outright belief is belief to degree 1. The latter thesis is rejected quickly in most discussions of the relationship between credence and belief, but the former thesis undermines the usual reasons for doing so. Furthermore, identifying belief with credence 1 allows nice solutions to a number of problems for the most widely-held view of the relationship between credence and belief, the threshold view. I provide a sketch (...) of a formal framework on which both theses are true. This is a modified Bayesian framework; I argue that despite making credences context-sensitive, the framework lets Bayesians hold on to their signature explanatory successes. The sort of context-sensitivity claimed for credences here mirrors the sort of context-sensitivity I have elsewhere claimed for outright belief: one's credences depend, in part, on the space of alternative possibilities one takes seriously in a context. (shrink)
Speaking is so closely associated with making noises that such descriptions as ‘silent soliloquy’ and ‘soundless monologue’ have an air of paradox. Yet people frequently say things to themselves in such a way that not even a close observer has any reason to think they have done so. It is therefore tempting to suppose that on such occasions a sequence of surrogate speech sounds is produced in the person's head which he alone hears or introaudits, as if what distinguishes silent (...) inner speech from normal speech is that the word substitutes are conveniently hidden from all save their producer. (shrink)
In 1981 Eleonore Stump and Norman Kretzmann published a landmark article aimed at exploring the classical concept of divine eternity. 1 Taking Boethius as the primary spokesman for the traditional view, they analyse God's eternity as timeless yet as possessing duration. More recently Brian Leftow has seconded Stump and Kretzmann's interpretation of the medieval position and attempted to defend the notion of a durational eternity as a useful way of expressing the sort of life God leads. 2 However, there are (...) good reasons to reject the idea that divine timelessness should be thought of as having duration. The medievals probably did not accept it, as it contradicts a principle of classical metaphysics even more fundamental than the atemporality of the divine. In any case, it is not possible to express the notion of durational eternity in even a minimally coherent way, and the attempt to salvage the concept by appealing to the Thomistic doctrine of analogy is unsuccessful. The best analogy for God's eternity is still the one proposed by Augustine at the end of the fourth century. God lives in a timeless ‘present’, unextended like our temporal present, but immutable and encompassing all time. (shrink)
The categories of reason and faith are often contrasted. When reason gives out, we are told that we have to rely on faith. Such exhortations are made particularly in the context of religion. When for instance, we face some personal tragedy which may well seem inexplicable, we are told that faith can help us through it. Very often faith is referred to in a vacuum. Presumably faith in God is usually meant, but all too often God drops out of the (...) picture, and it seems that all we need is faith, not faith in anything or anyone, but just faith. We are thus encouraged to add what seems to be a magic ingredient to our lives, which can transform everything. Perhaps at the back of such thinking lies some Calvinist notion of the corrupt character of human reason. As a result it may seem that we cannot rely on our judgment, which is the product of the fallen and sinful nature of humanity. Instead we must depend on ‘faith’ which may, or may not, be given us by the grace of God. (shrink)
He who has seen everything empty itself is close to knowing what everything is filled with. Emptiness is probably the most important philosophical and religious concept of Mahayana Buddhism. Its precise meaning has been explained differently by different schools and in different Buddhist cultures, but almost all Mahāyāna Buddhists would agree with the following characterization: Philosophically , emptiness is the term that describes the ultimate mode of existence of all phenomena, namely, as naturally ‘empty’ of enduring substance, or self-existence : (...) rather than being independently self-originated, phenomena are dependently originated from causes and conditions. Emptiness, thus, explains how it is that phenomena change and interact as they do, how it is that the world goes on as it does. Religiously , emptiness is the single principle whose direct comprehension is the basis of liberation from samsāra, and ignorance of which, embodied in self-gasping is the basis of continued rebirth – hence suffering – in samsāra. (shrink)
There is a certain attitude which makes freedom the main business of political thought and civil liberty the aim of government. I shall use the word ‘liberalism’ to refer to this attitude, in the hope that established usage will condone my description. And I shall explore and criticize two aspects of liberal thought: first, the concept of freedom in which it is based; secondly, the attack upon what Mill called the ‘despotism of custom’. My conclusions will be tentative; but I (...) should like to suggest that, properly understood, freedom and custom may require each other. Moreover to describe them as opposites is to make it impossible to see how either could be valued by a rational being, or why any politician should concern himself with their support or propagation. (shrink)
Human beings talk and co-operate, they build and produce, they work to accumulate and exchange, they form societies, laws and institutions, and, in all these things the phenomenon of reason—as a distinct principle of activity—seems dominant. There are indeed theories of the human which describe this or that activity as central—speech, say, productive labour, or political existence. But we feel that the persuasiveness of such theories depends upon whether the activity in question is an expression of the deeper essence, reason (...) itself, which all human behaviour displays. (shrink)
In a recent book devoted to giving an overview of cognitive science, Justin Lieber writes: …dazzingly complex computational processes achieve our visual and linguistic understanding, but apart from a few levels of representation these are as little open to our conscious view as the multitudinous rhythm of blood flow through the countless vessels of our brain. It is the aim of hundreds of workers in the allied fields of Cognitive Science and Artificial Intelligence to unmask these computation processes and install (...) them in digital computers. (shrink)
Roger Ariew presents a new account of Descartes as a philosopher who sought to engage his contemporaries and society. He argues that the Principles of Philosophy was written to rival Scholastic textbooks, and considers Descartes' enterprise in contrast to the tradition it was designed to replace and in relation to the works of the first Cartesians.
We claim that if a complete philosophy of evidence-based practice is intended, then attention to the nature of causation in health science is necessary. We identify how health science currently conceptualises causation by the way it prioritises some research methods over others. We then show how the current understanding of what causation is serves to constrain scientific progress. An alternative account of causation is offered. This is one of dispositionalism. We claim that by understanding causation from a dispositionalist stance, many (...) of the processes within an evidence-based practice framework are better accounted for. Further, some of the problems associated with the health research, e.g. external validity of causal findings, dissolve. (shrink)
This is the first comprehensive biography of John Locke to be published in nearly a half century. Setting Locke's life within exciting historical and intellectual contexts, which included the English Civil War, religious persecution, and the Glorious Revolution of 1688, Roger Woolhouse interweaves an account of Locke's life with a summary and development of his ideas in theory of knowledge, philosophy of science, medicine, economics, philosophy of religion, and political philosophy. Systematic and encyclopedic in its coverage, Woolhouse's biography offers (...) both an account and explanation of Locke's ideas, while treating seriously his emotional relationship with Elinor Parry. Based on broad research and many years of study of Locke's philosophy, this volume is an authoritative biography on one of the most significant early modern philosophers. (shrink)
Professor Roger T. Ames is Professor in the Department of Philosophy at the University of Hawai‘i, Manoa. The following is a short excerpt from an interview with Professor Ames that took place on the eve of 2009 PESA Conference, December 1, 2009. Heesoon Bai, Editor of Paideusis, accompanied by Avraham Cohen, interviewed Professor Ames in his office.
Composed more than 2,000 years ago during a turbulent period of Chinese history, the Dao de jing set forth an alternative vision of reality in a world torn apart by violence and betrayal. Daoism, as this subtle but enduring philosophy came to be known, offers a comprehensive view of experience grounded in a full understanding of the wonders hidden in the ordinary. Now in this luminous new translation, based on the recently discovered ancient bamboo scrolls, China scholars Roger T. (...) Ames and David L. Hall bring the timeless wisdom of the Dao de jing into our contemporary world. Though attributed to Laozi, “the Old Master,” the Dao de jing is, in fact, of unknown authorship and may well have originated in an oral tradition four hundred years before the time of Christ. Eschewing philosophical dogma, the Dao de jing set forth a series of maxims that outlined a new perspective on reality and invited readers to embark on a regimen of self-cultivation. In the Daoist world view, each particular element in our experience sends out an endless series of ripples throughout the cosmos. The unstated goal of the Dao de jing is self-transformation–the attainment of personal excellence that flows from the world and back into it. Responding to the teachings of Confucius, the Dao de jing revitalizes moral behavior by recommending a spontaneity made possible by the cultivated “habits” of the individual. In this elegant volume, Ames and Hall feature the original Chinese texts of the Dao de jing and translate them into crisp, chiseled English that reads like poetry. Each of the eighty-one brief chapters is followed by clear, thought-provoking commentary exploring the layers of meaning in the text. The book’s extensive introduction is a model of accessible scholarship in which Ames and Hall consider the origin of the text, place the emergence of Daoist philosophy in its historical and political context, and outline its central tenets. The Dao de jing is a work of timeless wisdom and beauty, as vital today as it was in ancient China. This new version will stand as both a compelling introduction to the complexities of Daoist thought and as the classic modern English translation. (shrink)
The preface paradox does not show that it can be rational to have inconsistent beliefs, because preface writers do not have inconsistent beliefs. I argue, first, that a fully satisfactory solution to the preface paradox would have it that the preface writer's beliefs are consistent. The case here is on basic intuitive grounds, not the consequence of a theory of rationality or of belief. Second, I point out that there is an independently motivated theory of belief – sensitivism – which (...) allows such a solution. I sketch a sensitivist account of the preface writer's doxastic state. (shrink)
This paper argues for a treatment of belief as essentially sensitive to certain features of context. The first part gives an argument that we must take belief to be context-sensitive in the same way that assertion is, if we are to preserve appealing principles tying belief to sincere assertion. In particular, whether an agent counts as believing that p in a context depends on the space of alternative possibilities the agent is considering in that context. One and the same doxastic (...) state may amount to belief that p in one context but not another. The second part of the paper gives a formal treatment of doxastic states, according to which belief is context-sensitive along just these lines. The model is applied to characterize (but not to refute) skeptical arguments. (shrink)
Preanalytically, we are all scientific realists. But both philosophers and scientists become uncomfortable when forced into analysis. In the case of scientists, this discomfort often arises from practical difficulties in setting out a carefully described set of objects which adequately account for the phenomena with which they are concerned. This paper offers a set of representative examples of these difficulties for contemporary physicists. These examples challenge the traditional realist vision of mature scientific activity as struggling toward an ontologically well-defined world (...) picture. They challenge antirealist alternatives as well. (shrink)