Modal epistemology made concrete

Many philosophers since Hume have accepted that imagining/conceiving a scenario is our prime guide to knowing its possibility. Stephen Yablo provided a more systematic criterion: one is justified in judging that p is possible if one can imagine a world which one takes to verify p. I defend a version of Yablo\u2019s criterion against van Inwagen\u2019s moderate modal scepticism. Van Inwagen\u2019s key argument is that we cannot satisfy Yablo\u2019s criterion because we are not in a position to spell out far-fetched possible scenarios in relevant detail. Van Inwagen\u2019s argument can be applied to the use of conceivability for everyday possibility claims, leaving us with the spectre of pervasive modal scepticism. In order to answer the sceptical threat, I combine van Inwagen\u2019s main example with general considerations about the nature of metaphysical modality to motivate a version of Yablo\u2019s criterion and show that it does not lead to scepticism. One structural condition of p being metaphysically possible is that it coheres with a complete reality. This condition gives rise to Yablo\u2019s criterion. However, for the criterion to be of any avail, we have to disregard details we are not in a position to specify. To account for our practice of doing so, I use Yablo\u2019s distinction between imagining a world as determinate and imagining it determinately. I present a condition when we may simply disregard details as determinate. The condition results from integrating analogical reasoning into the conceivability test

Counterfactual Conditionals : Orthodoxy and its Challenges

There is an intense debate in the philosophy of language and linguistics on so-called counterfactual conditionals. I shall introduce what I take to be the standard view: First, counterfactuals have truth–conditions. Second, these truth–conditions can be spelled out in terms of possible worlds. Third, the possible worlds deciding on the truth or falsity of a counterfactual are those that minimally differ from the actual world. Then I shall point out selected challenges to the standard view

Ab Esse ad Posse Non Valet Consequentia

While knowledge of mere possibilities is difficult to understand, knowledge of possibilities that are actual seems unproblematic (as far as we know the actual world). The principle that what is actual is possible has been near-universally accepted. After summarizing some sporadic dissent, I present a proposal for how the validity of the principle might be restricted. While the principle certainly holds for sufficiently inclusive objective and epistemic possibilities, it may not hold when the accessibility of possibilities is contextually restricted

Quantum-classical transition in Scale Relativity

The theory of scale relativity provides a new insight into the origin of fundamental laws in physics. Its application to microphysics allows us to recover quantum mechanics as mechanics on a non-differentiable (fractal) spacetime. The Schrodinger and Klein-Gordon equations are demonstrated as geodesic equations in this framework. A development of the intrinsic properties of this theory, using the mathematical tool of Hamilton's bi-quaternions, leads us to a derivation of the Dirac equation within the scale-relativity paradigm. The complex form of the wavefunction in the Schrodinger and Klein-Gordon equations follows from the non-differentiability of the geometry, since it involves a breaking of the invariance under the reflection symmetry on the (proper) time differential element (ds - ds). This mechanism is generalized for obtaining the bi-quaternionic nature of the Dirac spinor by adding a further symmetry breaking due to non-differentiability, namely the differential coordinate reflection symmetry (dx^mu - dx^mu) and by requiring invariance under parity and time inversion. The Pauli equation is recovered as a non-relativistic-motion approximation of the Dirac equation.Comment: 28 pages, no figur

Key informant perspectives on policy- and service-level challenges and opportunities for delivering integrated sexual and reproductive health and HIV care in South Africa

BACKGROUND: Integration of sexual and reproductive health (SRH) and HIV services is a policy priority, both globally and in South Africa. Recent studies examining SRH/HIV integration in South Africa have focused primarily on the SRH needs of HIV patients, and less on the policy and service-delivery environment in which these programs operate. To fill this gap we undertook a qualitative study to elicit the views of key informants on policy-and service-level challenges and opportunities for improving integrated SRH and HIV care in South Africa. This study comprised formative research for the development of an integrated service delivery model in KwaZulu-Natal (KZN) Province. METHODS: Semi-structured in-depth interviews were conducted with 21 expert key informants from the South African Department of Health, and local and international NGOs and universities. Thematic codes were generated from a subset of the transcripts, and these were modified, refined and organized during coding and analysis. RESULTS: While there was consensus among key informants on the need for more integrated systems of SRH and HIV care in South Africa, a range of inter-related systems factors at policy and service-delivery levels were identified as challenges to delivering integrated care. At the policy level these included vertical programming, lack of policy guidance on integrated care, under-funding of SRH, program territorialism, and weak referral systems; at the service level, factors included high client load, staff shortages and insufficient training and skills in SRH, resistance to change, and inadequate monitoring systems related to integration. Informants had varying views on the best way to achieve integration: while some favored a one-stop shop approach, others preferred retaining sub-specialisms while strengthening referral systems. The introduction of task-shifting policies and decentralization of HIV treatment to primary care provide opportunities for integrating services. CONCLUSION: Now that HIV treatment programs have been scaled up, actions are needed at both policy and service-delivery levels to develop an integrated approach to the provision of SRH and HIV services in South Africa. Concurrent national policies to deliver HIV treatment within a primary care context can be used to promote more integrated approaches

James Ellroy's Critical Criminology:Crimes of the Powerful in the Underworld USA Trilogy

This article argues for the criminological value of James Ellroy’s fiction, using hisUnderworld USA Trilogy (the “Trilogy”) as a case study. I present the Trilogy as a critical criminological enterprise, understood in the sense of providing a convincing explanation of the cause(s) of social harm—specifically, those committed by various agencies of the American government from the late-1950s to the early-1970s. Ellroy’s Trilogy provides this explanation in two distinct ways, using literary devices first to establish a counterfactual vision of America during the 1960s and then to represent the lived experience of perpetrators of state-sponsored social harm. In conveying such criminological knowledge, the Trilogy constitutes an instance of critical criminology and demonstrates the exercise of the criminological imagination

In Deadly Time: The Lasting On of Waste in Mayhew’s London

This paper examines the temporal dimension of waste in Henry Mayhew’s London Labour and the London Poor as an instance of how modernity has produced a largely hidden domain of the non-identical and indeterminate. Through a consideration of the phenomena of uselessness, decay and poverty I argue that the temporal dimension of waste is constituted as a corrosive or malign ‘Deadly Time.’ In placing such emphasis on time directed towards death, I aim to show that Mayhew’s undisciplined researches can be seen as a valuable source for understanding why modern thinking struggles to come to terms with waste

Nitrogen scavenging : using cover crops to reduce nitrate leaching in western Oregon

Willamette Valley field trials have shown that properly managed cover crops can reduce the amount of nitrate (NO3-)Declared out of print April 2010. Facts and recommendations in this publication may no longer be valid. Please look for up-to-date information in the OSU Extension Catalog: http://extension.oregonstate.edu/catalo

On the Matter of Time

Drawing on several disciplinary areas, this article considers diverse cultural concepts of time, space, and materiality. It explores historical shifts in ideas about time, observing that these have gone full circle, from visions in which time and space were conflated, through increasingly divergent linear understandings of the relationship between them, to their reunion in contemporary notions of space-time. Making use of long-term ethnographic research and explorations of the topic of Time at Durham University’s Institute of Advanced Study (2012–13), the article considers Aboriginal Australian ideas about relationality and the movement of matter through space and time. It asks why these earliest explanations of the cosmos, though couched in a wholly different idiom, seem to have more in common with the theories proposed by contemporary physicists than with the ideas that dominated the period between the Holocene and the Anthropocene. The analysis suggests that such unexpected resonance between these oldest and newest ideas about time and space may spring from the fact that they share an intense observational focus on material events. Comparing these vastly different but intriguingly compatible worldviews meets interdisciplinary aims in providing a fresh perspective on both of them

Development and Evolution of the Muscles of the Pelvic Fin

Locomotor strategies in terrestrial tetrapods have evolved from the utilisation of sinusoidal contractions of axial musculature, evident in ancestral fish species, to the reliance on powerful and complex limb muscles to provide propulsive force. Within tetrapods, a hindlimb-dominant locomotor strategy predominates, and its evolution is considered critical for the evident success of the tetrapod transition onto land. Here, we determine the developmental mechanisms of pelvic fin muscle formation in living fish species at critical points within the vertebrate phylogeny and reveal a stepwise modification from a primitive to a more derived mode of pelvic fin muscle formation. A distinct process generates pelvic fin muscle in bony fishes that incorporates both primitive and derived characteristics of vertebrate appendicular muscle formation. We propose that the adoption of the fully derived mode of hindlimb muscle formation from this bimodal character state is an evolutionary innovation that was critical to the success of the tetrapod transition