Most commonly, the scientific realism debate is seen as dividing those who do and do not think that the striking empirical and practical successes of at least our best scientific theories indicate with high probability that those theories are ‘approximately true’. But I want to suggest that this characterization of the debate has far outlived its usefulness. Not only does it obscure the central differences between two profoundly different types of contemporary scientific realist, but even more importantly it serves to (...) disguise the most substantial points of actual disagreement between these two kinds of realists and those who instead think the historical record of scientific inquiry itself reveals that such realism is untenable in either form. (shrink)

We analyse the extent of possible computations following Hogarth ([2004]) conducted in Malament–Hogarth (MH) spacetimes, and Etesi and Németi ([2002]) in the special subclass containing rotating Kerr black holes. Hogarth ([1994]) had shown that any arithmetic statement could be resolved in a suitable MH spacetime. Etesi and Németi ([2002]) had shown that some relations on natural numbers that are neither universal nor co-universal, can be decided in Kerr spacetimes, and had asked specifically as to the extent of computational limits there. (...) The purpose of this note is to address this question, and further show that MH spacetimes can compute far beyond the arithmetic: effectively Borel statements (so hyperarithmetic in second-order number theory, or the structure of analysis) can likewise be resolved: Theorem A. If H is any hyperarithmetic predicate on integers, then there is an MH spacetime in which any query ? n H ? can be computed. In one sense this is best possible, as there is an upper bound to computational ability in any spacetime, which is thus a universal constant of that spacetime. Theorem C. Assuming the (modest and standard) requirement that spacetime manifolds be paracompact and Hausdorff, for any spacetime there will be a countable ordinal upper bound, , on the complexity of questions in the Borel hierarchy computable in it. Introduction 1.1 History and preliminaries Hyperarithmetic Computations in MH Spacetimes 2.1 Generalising SADn regions 2.2 The complexity of questions decidable in Kerr spacetimes An Upper Bound on Computational Complexity for Each Spacetime CiteULike Connotea Del.icio.us What's this? (shrink)

We show how in the hierarchies${F_\alpha }$of Fieldian truth sets, and Herzberger’s${H_\alpha }$revision sequence starting from any hypothesis for${F_0}$ that essentially each${H_\alpha }$ carries within it a history of the whole prior revision process.As applications we provide a precise representation for, and a calculation of the length of, possiblepath independent determinateness hierarchiesof Field’s construction with a binary conditional operator. We demonstrate the existence of generalized liar sentences, that can be considered as diagonalizing past the determinateness hierarchies definable in Field’s recent (...) models. The ‘defectiveness’ of such diagonal sentences necessarily cannot be classified by any of the determinateness predicates of the model. They are ‘ineffable liars’. We may consider them a response to the claim of Field that ‘the conditional can be used to show that the theory is not subject to “revenge problems”.’. (shrink)

We consider various concepts associated with the revision theory of truth of Gupta and Belnap. We categorize the notions definable using their theory of circular definitions as those notions universally definable over the next stable set. We give a simplified account of varied revision sequences-as a generalised algorithmic theory of truth. This enables something of a unification with the Kripkean theory of truth using supervaluation schemes.

Aron Gurwitsch claims that the field of consciousness is invariantly organized in a theme, thematic field, margin pattern. However, at least two perceptual presentations, chaos and boundlessness, are not ordered in accordance with this pattern. The question this study poses then is the following: given Gurwitsch's field-theory of experiential organization, what is the structure, status, and function of chaos and boundlessness in the field of consciousness? ;Using Gurwitsch's field-theory organization as a base, the structure of thematic chaos and then of (...) thematic boundlessness is articulated: the first by contrasting the field-theories of Gurwitsch and James, the second by contrasting Gurwitsch and Kant. It is concluded that in both cases no thematic Gestalt-coherence and no thematic field as relevant context is presented. ;In terms of status and function, chaos and boundlessness are interpreted as necessary limits. These "limit cases" are not "ideal limits" since they are possible perceptual presentations. Also, limit is taken to mean a two-edged presentation, one that is both an ending and a beginning. Interpreting Gurwitsch, we conclude that both cases are epistemological endings, since they represent a necessary end to the ordinary perception of things. Interpreting James, we conclude that it is possible that thematic chaos is also a metaphysical beginning in experience, since it is that experience in which reality is presented as underived and original. Interpreting Kant, we conclude that it is possible that boundlessness is also an ethical beginning in experience, since it is that experience in which the most original feeling of our sense of humanity is presented. ;We show that chaos and boundlessness each have their own unique field-organization, that they function as two-edged limits involving epistemological concerns on the one hand and metaphysical and ethical concerns respectively on the other, and that their structure and status as limits in the field of consciousness are not contingent but necessary. (shrink)

This paper examines Hume’s ‘Title Principle’ and its role in a response to one of the ‘manifest contradictions’ he identifies in the conclusion to Book I of A Treatise on Human Nature. This ‘contradiction’ is a tension between two ‘equally natural and necessary’ principles of the imagination, our causal inferences and our propensity to believe in the continued and distinct existence of objects. The problem is that the consistent application of causal reason undercuts any grounds with have for the belief (...) in continued and distinct existence, and yet that belief is as ‘natural and necessary’ as our propensity to infer effects from causes. The TP appears to offer a way to resolve this ‘contradiction’. It statesWhere reason is lively, and mixes itself with some propensity, it ought to be assented to. Where it does not, it never can have any title to operate upon us.’ In brief, if it can be shown that the causal inferences that undermine the belief in external world are not ‘lively’ nor mixed with some propensity’ then we have grounds for think that they have no normative authority. This is in part a response to another ‘manifest contradiction’, namely the apparently self-undermining nature of reason. In this paper I examine the nature and grounds of the TP and its relation to these ‘manifest contradictions’. (shrink)

We look at various notions of a class of definability operations that generalise inductive operations, and are characterised as “revision operations”. More particularly we: (i) characterise the revision theoretically definable subsets of a countable acceptable structure; (ii) show that the categorical truth set of Belnap and Gupta’s theory of truth over arithmetic using \emph{fully varied revision} sequences yields a complete \Pi13 set of integers; (iii) the set of \emph{stably categorical} sentences using their revision operator ψ is similarly \Pi13 and which (...) is complete in Gödel’s universe of constructible sets L; (iv) give an alternative account of a theory of truth—realistic variance that simplifies full variance, whilst at the same time arriving at Kripkean fixed points. (shrink)

The figure of Peter the Tomb, various aspects of his life and activity, as well as the era called by his name, have long been the subject of study by numerous scholars, comprehensive and meticulous research. It is enough to mention the works of M.Grushevsky, A.Zhukovsky, V.Klimov, A.Kolodny, V.Nichik, O.Sarapin, L.Filipovich and V.Shevchenko, in which the phenomenon of the metropolitan, his spiritual and religious dominant, is thoroughly and thoroughly explained, the influence of P. Mogila's heritage on the past and present. (...) And yet it is impossible to talk about the exhaustiveness of this topic, because such inexhaustibility is dictated by the very universe of its multidimensional activity. This is what determines the relevance of the proposed article. And this, in turn, gives rise to reflections on the need for scientific innovative understanding of religious philosophy as a constant basis of thinking of Petro Mohyla, which, in particular, was reflected in his "Notebook", which is still a little-studied phenomenon of Ukrainian spiritual culture, for the first time it saw the world only in 1995, more than 60 years after its invention by M. Grushevsky. This work, like all narratives on the spiritual and religious themes that make up it, is an integral part of the metropolitan's religious and philosophical heritage. (shrink)

Evolutionary fitness threats and rewards are associated with subjectively unpleasant and pleasant sensations, respectively. Initially, these correlations appear explainable via adaptation by natural selection. But here I analyse the major metaphysical perspectives on consciousness – physicalism, dualism, and panpsychism – and conclude that none help to understand the adaptive-seeming correlations via adaptation. I also argue that a recently proposed explanation, the phenomenal powers view, has major problems that mean it cannot explain the adaptive-seeming correlations via adaptation either. So the mystery (...) – call it the evolutionary paradox of consciousness – remains. Some have used this mystery to argue for non-naturalistic (e.g. theistic) explanations. But I propose a naturalistic, non-adaptive explanation of the adaptive-seeming correlations: namely, ‘sensational associative learning’ during development. In this perspective, pairing of particular sensations with unconditioned stimuli – fitness rewards or threats – cause the sensations themselves to come to be interpreted as good or bad, respectively. Sensations, like colours, that are not reliably paired with either fitness rewards or threats remain largely unvalenced. Sensational associative learning also provides explanations for adaptive-seeming structural aspects of sensations, such as the observation that sounds of different pitch are experienced as ordinal in correspondence to their wavelengths while the same is not true of colours of different hue. The sensational associative learning perspective appears compatible with physicalism, panpsychism, and dualism (though not epiphenomenalism). (shrink)

In lieu of an abstract, here is a brief excerpt of the content:Hume Studies Volume 29, Number 1, April 2003, pp. 125-141 Dr. George Cheyne, Chevalier Ramsay, and Hume's Letter to a Physician JOHN P. WRIGHT The publication of a new intellectual biography of George Cheyne1 provides a "propitious" occasion for "a thoroughly skeptical review"2 of the question which has long exercised Hume scholars, whether Cheyne was the intended recipient of David Hume's fascinating pie-Treatise Letter to a Physician,3 the letter (...) which describes his own hypochondriacal physical and mental symptoms and gives an account of his early philosophical development.4 Hume's nineteenth-century biographer, John Hill Burton, argued that Hume was probably writing to Cheyne,5 while Ernest Mossner claimed to definitively refute that hypothesis in an article entitled "Hume's Epistle to Dr. Arbuthnot," published in 1944.6 Anita Guerrini's intellectual biography does not discuss Cheyne as a possible recipient of Hume's letter, but she does present a well-rounded picture of this interesting eighteenth-century physician from which we can judge his appropriateness as its addressee. In the following discussion I will make use of the biographical material found in this new biography of Cheyne, as well as other sources, to show that Mossner's arguments are less than definitive, and that it would be wrong to dismiss the possibility that the letter was sent to George Cheyne.7 This is a possibility that, for reasons that I will make clear, makes good biographical and philosophical sense. At the same time, it is important to keep a proper suspense of judgment as Burton did, for the evidence that the letter was either intended for or actually sent to Cheyne is not definitive. John P. Wright is Professor of Philosophy, Central Michigan University, Mt. Pleasant, MI 48859, USA. e-mail: [email protected] 126 John P. Wright Burton, who first published the autobiographical letter of the 22-yearold Hume in 1846, narrowed down the possible addressees of Hume's letter to either Cheyne or John Arbuthnot. He also pointed out that it is possible that the letter was never sent, and that the ten and a half page manuscript is only a neatly written draft, rather than a fair copy of an actual letter. Nevertheless, Burton thought he could identify the unnamed addressee on the basis of the internal evidence of the manuscript and the records of Scottish physicians practicing in England at the time. In the letter, Hume refers to the intended recipient as his "Countryman, a Scotchman [,]... a skilful Physician, a man of Letters, of Wit, of Good Sense, & of great Humanity."8 Further he writes that he is consulting him because he is a person "of great Learning beyond [his]... own Profession" who is acquainted with the "Motions of the Mind" he has described in his letter, and that "Fame pointed [him]... out as the properest person to resolve my Doubts..." about the cure of his disorder.9 Burton tells us that "the first name that suggested itself... was Arbuthnot, whose fine genius was just then flickering in the socket."10 (John Arbuthnot had been ill for some time, and died a year later.) But he then added that "a more full consideration showed to my satisfaction that it must have been destined for Dr. George Cheyne." His main reason for settling on Cheyne was that Cheyne's immensely popular The English Malady (1733) had recently been published, and that "there is a certain unison of tone between Hume's letter and this book." Burton quotes a portion of Cheyne's own long autobiographical account of his own disease in The English Malady. Cheyne's autobiography begins with the claim that "I passed my Youth in close study, and almost constant Application to the abstracted Sciences, (wherein my chief pleasure consisted) and consequently in great Temperance and a Sedentary Life"; it is followed by the reflection that any overindulgence in food or drink led to physical and psychological problems.11 He goes on to describe these in great detail for 39 pages, along with a history of his life. Burton also quotes a section of the book in which Cheyne describes how a studious and sedentary life causes the symptoms... (shrink)

The central limit theorem has been found to apply to random vectors in complex Hilbert space. This amounts to sufficient reason to study the complex–valued Gaussian, looking for relevance to quantum mechanics. Here we show that the Gaussian, with all terms fully complex, acting as a propagator, leads to Schrödinger’s non-relativistic equation including scalar and vector potentials, assuming only that the norm is conserved. No physical laws need to be postulated a priori. It thereby presents as a process of irregular (...) motion analogous to the real random walk but executed under the rules of the complex number system. There is a standard view that Schrödinger’s equation is deterministic, whereas wavefunction “collapse” is probabilistic —we have now a demonstrated linkage to the central limit theorem, indicating a stochastic picture at the foundation of Schrödinger’s equation itself. It may be an example of Wheeler’s “It from bit” with “No underlying law”. Reasons for the primary role of \ are open to discussion. The present derivation is compared with recent reconstructions of the quantum formalism, which have the aim of rationalizing its obscurities. (shrink)

Some of human evil is a function of the historical stage of society. The evils and wickednesses of bureaucracy are as old as well‐developed bureaucratic hierarchies. Evil‐doers have character traits that may form recognizable patterns with explanatory weight. Evil‐doers produce reasons for their evil‐doing and offer justifications for their evil deeds. Psychological experiments may indeed establish important correlations and statistical probabilities that may be crucial for the formation of intelligent social policy. The greatest students of the place of evil in (...) human life and of the subjective psychology of evil in a complex social setting are great novelists, dramatists, and poets. From the late eighteenth century onwards ideological beliefs played a major role in stimulating evil, not for the greater glory of God but for the future glory of man. The first major social movement that bent an ideology to wholly evil policies were the Jacobins during the French Revolution. (shrink)

What one has when one imagines something or when one sees something is not something which others, by contrast with oneself cannot see. For one does not see one's mental images or visual impressions. It makes sense to talk of oneself as having a visual impression or mental image only if it also makes sense to talk of someone else having the same impression or image. To talk of things being blurred at the edge of one's visual field (unlike talk (...) of images on a photograph being blurred), of conjuring up an image of something revolving, is to introduce a new way of speaking. Idealists and solipsists attack the normal form of expression as if the mere form stated how things are; whereas the only cogent case that can be made out in their favour is a recommendation to adopt a different form in which the very same facts are represented in different guise. (shrink)

This paper considers a possible national cultural and scientific synthesis which failed to take place: namely the integration of the Central European theoretical physicist Erwin Schrödinger into the primarily experimental orientations of the Oxford physics of the 1930s. We also consider the effect of the Oxford social and intellectual atmosphere generally, incluing the persistence of previous traditions which undervalued Science relative to the Arts, and University research relative to tutorial provision in the Colleges. The Oxford situation is then briefly contrasted (...) to that which Schrödinger later found in Dublin between 1939 and 1956, and which was to have a significantly more productive outcome. (shrink)