[Sensation, Causality, and Attention: Roger Bacon and Peter Olivi] This paper investigates what conditions are to be met for sensory perception to occur. It introduces two diff erent theories of perception that were held by two medieval Franciscan thinkers — namely, Roger Bacon (1214/1220–1292) and Peter Olivi (ca. 1248–1298). Bacon analyses especially the causal relation between the object and the sensory organ in his doctrine of the multiplication of species. In his view, a necessary condition of perception is (...) the reception of the species in a fully disposed sensory organ. On the contrary, Olivi stresses the active role of the sensory power. A necessary condition of sensation is the aspectus — i.e. the focus of our power’s attention on the object. Furthermore, the paper investigates whether and how each of the two thinkers can deal with the arguments proposed by his opponent — namely whether Bacon’s theory is able to explain attention and what the causal role of the object in Olivi’s theory is. (shrink)
Whereas there are many aspects of Roger Simon’s thought that can be privileged, one of the most compelling points of entry for beginning to consider his legacy in the field of education, and beyond, lies with his concern for the difficult work of receiving and transmitting, of giving countenance to, the traces of those now absent. Indeed, in the last 20 years of his scholarly work, Simon pressed us to consider the pedagogical stakes in forging an ethical living relation (...) with the remnants of past and presently unsettled—ongoing—historical wrongs. Keenly aware of how memorial practices risk falling into facile assurances and deferrals, Simon emphasized the important work of “remembrance-learning,” in which the task is to learn how to ethically receive and translate the remnants of a difficult past in our present, so that we might be able to more thoroughly think our time. In this paper I provide an overview of a certain tendency in Simon’s later thinking, pointing to how his work on pedagogy, aesthetics, curation and collective study was motivated by a not so ordinary way of thinking that takes seriously the fact that the dead cannot bury the dead; that they need those in the present, those whose turn it is to do the work, to offer human significance and a human completion to what remains a remnant. (shrink)
ROGER SCRUTON’s An Intelligent Person’s Guide to Philosophy takes a personal and provocative look at the subject—those abstract, but nevertheless practical, problems that concern anyone who has reflected on his or her life. Of special delight is his discussion of sex and music. I make some brief critical comments on this based on new economic approaches.
Medical futility, one of the most debated end-of-life issues in medical ethics, has been discussed among physicians and scholars for years but remained an unresolved question. Roger C. Bone (1941–1997), an outstanding pulmonologist and critical care specialist, devoted his last years to ethical issues of terminal care, while facing himself metastatic renal cancer. Criticising the abuse of technology in terminal care and the administrative and financial interference on medical decisions, he bequeathed important points on futility, bringing also patients’ views (...) into attention. He stressed the importance of physician-patient relationship and prompted physicians to remain honest with their patients and stand with them till their very last moments. Roger Bone’s insight of futility, terminal care and physician-patient relationship remains an important legacy for health care professionals and for families and patients facing end-of-life issues. (shrink)
In his latest book,Roger Penrose deals with three foundational problems of current physics fromhis particularly fresh perspective.He criticizes mainstream string the- ories, standard interpretations of quantum mechanics, and pre-Big Bang cosmolo- gies inasmuch as they aim to solve profound questions while glossing over equally deep issues in our understanding of nature. In this review, I analyze Penrose’s main arguments, emphasizing his presentation of the Second Law conundrum as “the most profound mystery of cosmology”, and discuss his own proposals to (...) overcome the impasse. I especially focus on the capabilities of conformal cyclic cosmology to illuminate the enigma of the extraordinarily low entropy at the Big Bang and review its capacity of success in stipulating a reset for the entropy of the universe. Even though one need not follow Penrose’s tentative answers, which are not immune to serious critiques, much of his view can be shared as a sound starting point in search of “the new physics of the universe.”. (shrink)
Roger Bastide a été un des rares sociologues français de sa génération à ne pas se reconnaître d’emblée héritier de Durkheim, auquel il reprochait son « sociologisme ». Toute l’œuvre de Bastide peut être caractérisée comme une tentative d’articulation du « fait individuel », du fait social et du fait culturel. L’attention qu’il portait à la subjectivité des individus explique l’intérêt qu’il a très tôt éprouvé pour les travaux des chercheurs de l’École de Chicago, qu’il a découverts en grande (...) partie pendant son long séjour au Brésil et qu’il a été un des premiers à faire connaître en France par ses enseignements et ses publications.Roger Bastide was one of the few French sociologists of his generation who did not declare himself to be heir to Durkheim. On the contrary, he criticized the latter for his « sociologism ». All Bastide’s work can be described as an attempt to connect the « individual fact » with social and cultural facts. The attention he paid to the subjectivity of individuals accounts for his interest, early on, in the work of the Chicago School, which he discovered during a long stay in Brazil. Bastide was one of the first to try, through his teaching and writings, to call the attention of French academics to the work of the Chicago School. (shrink)
The fundamental premise of Trigg's book is that philosophy is an irreplaceable discipline, and Trigg seeks to defend it from the Scylla of scientism and the Charibdis of relativism. His bold tone will engage many readers in the challenges he discusses.
In this paper I challenge the claim that Bacon considered the operation of species as limited to the physical and sensory levels and demonstrate that in his view, the very same species issued by physical objects operate within the intellect as well. I argue that in Bacon the concept of illumination plays a secondary role in the acquisition of knowledge, and that he regarded innate knowledge as dispositional and confused. What was left as the main channel through which knowledge is (...) gained were species received through the senses. I argue that according to Bacon these species, representing their agents in essence, definition and operation, arrive in the intellect without undergoing a complete abstraction from matter and while still retaining the character of agents acting naturally. In this way Bacon sets the intellect as separate from the natural world not in any essential way, but rather as it were in degree, thus supplying a theoretical justification for the ability to access and know nature. (shrink)
The aim of the presented article is to provide an in-depth analysis of the adequacy of designating Penrose as a complex Pythagorean in view of his much more common designation as a Platonist. Firstly, the original doctrine of the Pythagoreans will be briefly surveyed with the special emphasis on the relation between the doctrine of this school and the teachings of the late Platonic School as well as its further modifications. These modifications serve as the prototype of the contemporary claims (...) of the mathematicity of the Universe. Secondly, two lines of Penrose’s arguments in support of his unique position on the ontology of the mathematical structures will be presented: their existence independent of the physical world in the atemporal Platonic realm of pure mathematics and the mathematical structures as the patterns governing the workings of the physical Universe. In the third step, a separate line of arguments will be surveyed that Penrose advances in support of the thesis that the complex numbers seem to suit these patterns with exceptional adequacy. Finally, the appropriateness of designation Penrose as a complex Pythagorean will be assessed with the special emphasis on the suddle threshold between his unique position and that of the adherents of the mathematicity of the Universe. (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)
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)
In his stimulating book SHADOWS OF THE MIND, Roger Penrose presents arguments, based on Gödel's theorem, for the conclusion that human thought is uncomputable. There are actually two separate arguments in Penrose's book. The second has been widely ignored, but seems to me to be much more interesting and novel than the first. I will address both forms of the argument in some detail. Toward the end, I will also comment on Penrose's proposals for a "new science of consciousness".
According to the Imprecise Credence Framework (ICF), a rational believer's doxastic state should be modelled by a set of probability functions rather than a single probability function, namely, the set of probability functions allowed by the evidence ( Joyce  ). Roger White (  ) has recently given an arresting argument against the ICF, which has garnered a number of responses. In this article, I attempt to cast doubt on his argument. First, I point out that it's not (...) an argument against the ICF per se , but an argument for the Principle of Indifference. Second, I present an argument that's analogous to White's. I argue that if White's premises are true, the premises of this argument are too. But the premises of my argument entail something obviously false. Therefore, White's premises must not all be true. (shrink)
In his book Shadows of the Mind: A search for the missing science of con- sciousness [SM below], Roger Penrose has turned in another bravura perfor- mance, the kind we have come to expect ever since The Emperor’s New Mind [ENM ] appeared. In the service of advancing his deep convictions and daring conjectures about the nature of human thought and consciousness, Penrose has once more drawn a wide swath through such topics as logic, computa- tion, artiﬁcial intelligence, quantum (...) physics and the neuro-physiology of the brain, and has produced along the way many gems of exposition of diﬃcult mathematical and scientiﬁc ideas, without condescension, yet which should be broadly appealing.1 While the aims and a number of the topics in SM are the same as in ENM , the focus now is much more on the two axes that Pen- rose grinds in earnest. Namely, in the ﬁrst part of SM he argues anew and at great length against computational models of the mind and more speciﬁ- cally against any account of mathematical thought in computational terms. Then in the second part, he argues that there must be a scientiﬁc account of consciousness but that will require a (still to be found) non-computational extension or modiﬁcation of present-day quantum physics. (shrink)
Al final de su libro “La conciencia inexplicada”, Juan Arana señala que la nomología, explicación según las leyes de la naturaleza, requiere de una nomogonía, una consideración del origen de las leyes. Es decir, que el orden que observamos en el mundo natural requiere una instancia previa que ponga ese orden específico. Sabemos que desde la revolución científica la mejor manera de explicar dicha nomología ha sido mediante las matemáticas. Sin embargo, en las últimas décadas se han presentado algunas propuestas (...) basadas en modelos matemáticos que fundamentarían muchos aspectos de la realidad. Dos claros ejemplos provienen de Roger Penrose y Max Tegmark. Esto lleva a pensar en una posición no solo nomológica sino además nomogónica de la matemática. ¿Puede la Naturaleza estar fundada por las matemáticas como señalan algunos físico-matemáticos? Y en ese caso, ¿sería pertinente buscar una nomo-génesis de esta índole en la constitución de la conciencia? -/- At the end of his book “La conciencia inexplicada”, Juan Arana points out that nomology, explanation according to the laws of nature requires a nomogony, an account of the origin of the laws. This means that the order that we can observe in the natural World demands something prior to posit that specific order. Since the scientific revolution we know that the best way to explain that nomology has been through mathematics. Anyway, in recent decades a number of proposals based on mathematical models that found many aspects of reality has been offered. Two clear examples come from Roger Penrose and Max Tegmark. This drives us to think of a position of mathematics as not only nomological but also nomogonical. Can Nature be founded by mathematics as some physicists and mathematicians point out? And, in this case, would be relevant this kind of approach to search a nomo-genesis in the constitution of consciousness? (shrink)
In the 1330s Roger Swyneshed formulated a solution to semantic paradoxes based on the distinction between correspondence with reality and self-falsification as truth-making factors. Since Swyneshed states that some valid inferences are not truth-preserving, his view implies the question of the general definition of validity which he does not address explicitly. Logical works attributed to Paul of Venice contain developments of Swyneshed's contextualist semantics substantially modified by the assumption that sentential meanings are objective propositional entities. The main goals of (...) this paper are to show the correlations between the ontological and logical developments of Swyneshed's semantics in the works of Paul of Venice and to outline a context-sensitive formal semantics that could serve as a model of this family of semantic theories. (shrink)
Luc Brisson’s translation and challenging interpretation of the Parmenides stands out as one of the most influential contributions to contemporary exegesis of Plato’s arguably most controversial dialogue. While acknowledging its many virtues, the essay rejects Brisson’s understanding of the text’s focus and purpose. Brisson’s methodological assumptions are especially discussed and proven to be highly questionable on account of a rather straightforward transfer of the doxographical concerns which Plato is supposed to share with contemporary historians of Parmenides’ philosophy.
This case study focuses on Roger Boisjoly's attempt to prevent the launch of the Challenger and subsequent quest to set the record straight despite negative consequences. Boisjoly's experiences before and after the Challenger disaster raise numerous ethical issues that are integral to any explanation of the disaster and applicable to other management situations. Underlying all these issues, however, is the problematic relationship between individual and organizational responsibility. In analyzing this fundamental issue, this paper has two objectives: first, to demonstrate (...) the extent to which the ethical ambiguity that permeates the relationship between individual and organizational responsibility contributed to the Challenger disaster; second, to reclaim the meaning and importance of individual responsibility within the diluting context of large organizations. (shrink)
Roger Crisp distinguishes a positive and a negative aspect of the buck-passing account of goodness (BPA), and argues that the positive account should be dropped in order to avoid certain problems, in particular, that it implies eliminativism about value. This eliminativism involves what I call an ontological claim, the claim that there is no real property of goodness, and an error theory, the claim that all value talk is false. I argue first that the positive aspect of the BPA (...) is necessary to explain the negative aspect. I accept the ontological claim but argue that this does not imply any sort of error theory about value. (shrink)
This issue of Contemporary Chinese Thought presents selected addresses and papers from the first symposium hosted by the newly established Discussion Forum of Confucianism at the Sage's Birthplace, at Nishan, in Sishui county of Shandong province, which took place June 22-26, 2009. The "Symposium Celebrating Roger T. Ames's Scholarship on Confucianism" honored the University of Hawai'i professor of Chinese philosophy as a distinguished scholar and an extraordinary teacher and mentor.
In this article, I examine the meaning of the concept of ?civility? for Roger Williams and the role it played in his arguments for religious toleration. I place his concern with civility in the broader context of his life and works and show how it differed from the missionary and civilizing efforts of his fellow New English among the American Indians. For Williams, civility represented a standard of inclusion in the civil community that was ?essentially distinct? from Christianity, which (...) properly governed membership in the spiritual community of the church. In contrast to recent scholarship that finds in Williams a robust vision of mutual respect and recognition between co-citizens, I argue that civility constituted rather a very low bar of respectful behavior towards others entirely compatible with a lack of respect, disapproval, and even disgust for them and their beliefs. I show further that civility for Williams was consistent with?and partially secured by?a continued commitment on the part of godly citizens to the potential conversion of their neighbors. Williams endorsed this ?mere? civility as a necessary and sufficient condition for toleration while also delineating a potentially expansive role for the magistrate in regulating incivility. Contemporary readers of William who conflate civility with other good things, such as mutual respect, recognition, and civic friendship, slide into a position much like that he was trying to refute. (shrink)
This is a critical review of Roger Crisp's The Cosmos of Duty. The review praises the book but, among other things, takes issue with some of Crisp's criticisms of Sidgwick's view that resolution of the free will problem is of limited significance to ethics and with Crisp's claim that in Methods III.xiii Sidgwick defends an axiom of prudence that undergirds rational egoism.
Comments on Roger Ariew’s “Descartes and Leibniz as Readers of Suarez," presented at Franscico Suarez, S.J.: Last Medieval or First Early Modern?, London, Ontario, University of Western Ontario, September 2008.
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)
"The Emperor's New Mind" by Roger Penrose has received a great deal of both praise and criticism. This review discusses philosophical aspects of the book that form an attack on the "strong" AI thesis. Eight different versions of this thesis are distinguished, and sources of ambiguity diagnosed, including different requirements for relationships between program and behaviour. Excessively strong versions attacked by Penrose (and Searle) are not worth defending or attacking, whereas weaker versions remain problematic. Penrose (like Searle) regards the (...) notion of an algorithm as central to AI, whereas it is argued here that for the purpose of explaining mental capabilities the architecture of an intelligent system is more important than the concept of an algorithm, using the premise that what makes something intelligent is not what it does but how it does it. What needs to be explained is also unclear: Penrose thinks we all know what consciousness is and claims that the ability to judge Go "del's formula to be true depends on it. He also suggests that quantum phenomena underly consciousness. This is rebutted by arguing that our existing concept of "consciousness" is too vague and muddled to be of use in science. This and related concepts will gradually be replaced by a more powerful theory-based taxonomy of types of mental states and processes. The central argument offered by Penrose against the strong AI thesis depends on a tempting but unjustified interpretation of Goedel's incompleteness theorem. Some critics are shown to have missed the point of his argument. A stronger criticism is mounted, and the relevance of mathematical Platonism analysed. Architectural requirements for intelligence are discussed and differences between serial and parallel implementations analysed. (shrink)
Apart from being a prolific philosopher, Roger Scruton is also an accomplished writer of novels, poems, short stories, libretti and literary memoirs. In this article I will explore how Scruton's literary writings relate to his philosophy. I shall argue that one concept, pivotal to Scruton's philosophy, is also a main Leitmotiv of his literary work: home. The longing to be at home in the world is integral to our human nature. Several phenomena, as Scruton shows in his philosophy and (...) literary works, are indispensable in order for us to be able to fulfil the desire to belong: beauty, oikophilia, and the ability to engage with each other as persons. (shrink)
A response to a critique by Roger W. Hunt of my views on the eventual likely need to use age as a standard for the allocation of expensive, high-technology, life-extending medical care for the elderly. The response encompasses three elements: 1. that while the elderly have a substantial claim to publicly-provided health care, it cannot be an unlimited claim; 2. that a health care system which provided a decent, coherent set of medical and social services for the elderly would (...) be sufficient, even if some limits had to be set; and 3. allocation and rationing decisions should not be made by individual doctors at the bedside but by regional or national policy. (shrink)
In [Dutilh Novaes, Medieval-obligations as logical Games of Consistency maintenance, synthese, (2004)], I proposed a reconstruction of Walter Burley’s theory of obligationes, based on the idea that Burley’s theory of obligationes could be seen as a logical game of consistency maintenance. In the present paper, I intend to test the game hypothesis on another important theory of obligationes, namely Roger Swyneshed’s theory. In his treatise on obligationes [edited by P.V. Spade, cf. Spade History and philosophy of Logic 3(1982) 1-32], (...) Swyneshed introduced significant modifications to the general framework of obligationes. To compare the two theories, I apply the same formal apparatus used in the previous paper. It will become patent that Swyneshed’s theory is considerably different from Burley’s, among other reasons because the dynamic aspects that play a major role in the latter are simply not present in the former. My conclusion is that Swyneshed’s version of obligationes is not directed towards consistency maintenance, but rather towards inference recognition, and that it is, from a game-theoretical perspective, less interesting a theory than Burley’s. (shrink)
Roger Gottlieb's Morality and the Environmental Crisis is a philosophical overview of the choices that will shape our grandchildren's lives, as dramatized in his speculative sketch of two very different futures at the end of this book. Gottlieb more than once notes that he is in his seventh decade of life, appropriately designating this work as that of an elder passing on the knowledge derived from his long career as a scholar, teacher, activist linking environmentalist with spiritual communities, and (...) the father of a daughter with special needs. First on his list of potential actions for addressing the environmental crisis is writing a book such as this to encourage readers to share his conviction of the need for... (shrink)
A critical edition and facing-page translation, accompanied by substantial analytical introduction and notes, of Perspectiva by Roger Bacon, a foundational text of modern optics written in about 1260, which defined the subject for the next 350 years.
did roger bacon and peter john olivi ever meet? We suggest a positive answer to this question. After he became a Franciscan in 1257, Roger Bacon spent ten years at the Franciscan Paris convent. In those years he wrote the De multiplicatione specierum —his most thought-out piece—the Opus majus, Opus minus, and Opus tertium, which he completed by early 1268. It is not clear whether Bacon returned to England after 1268, or remained in Paris until 1280.1 Peter John (...) Olivi wrote the Summa questions in several phases.2 According to Sylvain Piron's chronology, Olivi's questions on Physics should be dated before 1270, and his theory of... (shrink)