A Q -Heyting algebra is an algebra of type such that is a Heyting algebra and the unary operation ∇ satisfies the conditions ∇0=0, a ∧∇ a = a , ∇=∇ a ∧∇ b and ∇=∇ a ∨∇ b , for any a , b ∈ H . This paper is devoted to the study of the subvariety QH L of linear Q -Heyting algebras. Using Priestley duality we investigate the subdirectly irreducible linear Q -Heyting algebras and, as consequences, we (...) derive some properties of the lattice of subvarieties of QH L and find equational bases for some of these subvarieties. (shrink)
En este trabajo se presenta una comparación de los tiempos de respuesta, optimización de la ruta y complejidad del grafo en métodos de planificación de trayectoria para robots móviles autónomos. Se contrastan los desarrollos de Voronoi, Campos potenciales, Roadmap probabilístico y Descomposición en celdas para la navegación en un mismo entorno y validándolos para un número variable de obstáculos. Las evaluaciones demuestran que el método de generación de trayectoria por Campos Potenciales, mejora la navegación respecto de la menor ruta obtenida, (...) el método Rapidly Random Tree genera los grafos de menor complejidad y el método Descomposición en celdas, se desempeña con menor tiempo de respuesta y menor coste computacional. Palabras Clave: optimización, trayectoria, métodos de planificación, robots móviles. Referencias H. Ajeil, K. Ibraheem, A. Sahib y J. Humaidi, “Multi-objective path planning of an autonomous mobile robot using hybrid PSO-MFB optimization algorithm, ” Applied Soft Computing, vol. 89, April 2020. K.Patle, G. Babu, A. Pandey, D.R.K. Parhi y A. Jagadeesh, “A review: On path planning strategies for navigation of mobile robot,” Defence Technology, vol. 15, pp. 582-606, August 2019. T. Mack, C. Copot, D. Trung y R. De Keyser, “Heuristic approaches in robot path planning: A survey,” Robotics and Autonomous Systems, vol. 86, pp. 13-28, December 2016. L. Zhang, Z. Lin, J. Wang y B. He, “Rapidly-exploring Random Trees multi-robot map exploration under optimization framework,” Robotics and Autonomous Systems, vol. 131, 2020. S. Khan y M. K. Ahmmed, "Where am I? Autonomous navigation system of a mobile robot in an unknown environment," 2016 5th International Conference on Informatics, Electronics and Vision, pp. 56-61, December 2016. V. Castro, J. P. Neira, C. L. Rueda, J. C. Villamizar y L. Angel, "Autonomous Navigation Strategies for Mobile Robots using a Probabilistic Neural Network," IECON 2007 - 33rd Annual Conference of the IEEE Industrial Electronics Society, pp. 2795-2800, Taipei, 2007. Y. Li, W. Wei, Y. Gao, D. Wang y C. Fan, “PQ-RRT*: An improved path planning algorithm for mobile robots,” Expert Systems with Applications, vol. 152, August 2020. A. Muñoz, “Generación global de trayectorias para robots móviles, basada en curvas betaspline,” Dep. Ingeniería de Sistemas y Automática Escuela Técnica Superior de Ingeniería Universidad de Sevilla, 2014. H. Montiel, E. Jacinto y H. Martínez, “Generación de Ruta Óptima para Robots Móviles a Partir de Segmentación de Imágenes,” Información Tecnológica, vol. 26, 2015.  C. Expósito, “Los diagramas de Vornooi, la forma matemática de dividir el mundo,” Dialnet, Diciembre 2016. (shrink)
H. B. D. Kettlewell's field experiments on industrial melanism in the peppered moth, Biston betularia, have become the best known demonstration of natural selection in action. I argue that textbook accounts routinely portray this research as an example of controlled experimentation, even though this is historically misleading. I examine how idealized accounts of Kettlewell's research have been used by professional biologists and biology teachers. I also respond to some criticisms of David Rudge to my earlier discussions of this case study, (...) and I question Rudge's claims about the importance of purely observational studies for the eventual acceptance and popularization of Kettlewell's explanation for the evolution of industrial melanism. (shrink)
Scientific misconduct obstructs the advance of knowledge in science. Its impact in some disciplines is still poorly known, as is the frequency in which it is detected. Here, I examine how frequently editors of ecology and evolution journals detect scientist misconduct. On average, editors managed 0.114 allegations of misconduct per year. Editors considered 6 of 14 allegations (42.9%) to be true, but only in 2 cases were the authors declared guilty, the remaining being dropped for lack of proof. The annual (...) rate of allegations that were probably warranted was 0.053, although the rate of demonstrated misconduct was 0.018, while the rate of false or erroneous allegations was 0.024. Considering that several cases of misconduct are probably not reported, these findings suggest that editors detect less than one-third of all fraudulent papers. (shrink)
This paper seeks to reinterpret the life and work of J. B. S. Haldane by focusing on an illuminating but largely ignored essay he published in 1927, "The Last Judgment" -- the sequel to his better known work, "Daedalus" (1924). This astonishing essay expresses a vision of the human future over the next 40,000,000 years, one that revises and updates Wellsian futurism with the long range implications of the "new biology" for human destiny. That vision served as a kind of (...) lifelong credo, one that infused and informed his diverse scientific work, political activities, and popular writing, and that gave unity and coherence to his remarkable career. (shrink)
The historical background of the 19th century electromagnetic theory is revisited from the standpoint of the opposition between alternative approaches in respect to the problem of interactions. The 19th century electrodynamics became the battle-field of a paramount importance to test existing conceptions of interactions. Hertz’s experiments were designed to bring a solid experimental evidence in favor of one of them. The modern scientific method applied to analyze Hertz’s experimental approach as well as the analysis of his laboratory notes, dairy and (...) private letters show that Hertz’s ‘‘crucial’’ experiments cannot be considered as conclusive at many points as it is generally implied. We found that alternative Helmholtz’s electrodynamics did not contradict any of Hertz’s experimental observations of transverse components as Maxwell’s theory predicted. Moreover, as we now know from recently published Hertz’s dairy and private notes, his first experimental results indicated clearly on infinite rate of propagation. Nevertheless, Hertz’s experiments provided no further explicit information on non-local longitudinal components which were such an essential feature of Helmholtz’s theory. Necessary and sufficient conditions for a decisive choice on the adequate account of electromagnetic interactions are discussed from the position of modern scientific method. (shrink)
Among moral attributes true virtue alone is sublime. … [I]t is only by means of this idea [of virtue] that any judgment as to moral worth or its opposite is possible. … Everything good that is not based on a morally good disposition … is nothing but pretence and glittering misery. 1.
Close insight into mathematical and conceptual structure of classical field theories shows serious inconsistencies in their common basis. In other words, we claim in this work to have come across two severe mathematical blunders in the very foundations of theoretical hydrodynamics. One of the defects concerns the traditional treatment of time derivatives in Eulerian hydrodynamic description. The other one resides in the conventional demonstration of the so-called Convection Theorem. Both approaches are thought to be necessary for cross-verification of the standard (...) differential form of continuity equation. Any revision of these fundamental results might have important implications for all classical field theories. Rigorous reconsideration of time derivatives in Eulerian description shows that it evokes Minkowski metric for any flow field domain without any previous postulation. Mathematical approach is developed within the framework of congruences for general four-dimensional differentiable manifold and the final result is formulated in form of a theorem. A modified version of the Convection Theorem provides a necessary cross-verification for a reconsidered differential form of continuity equation. Although the approach is developed for one-component (scalar) flow field, it can be easily generalized to any tensor field. Some possible implications for classical electrodynamics are also explored. (shrink)
Transhumanism is a challenging movement that invites us to rethink what defines humanity, including what we value and regret the most about our existence. Vulnerability is a key concept that require thorough philosophical scrutiny concerning transhumanist proposals. Vulnerability can refer to a universal condition of human life or, rather, to the specific exposure to certain harms due to particular situations. Even if we are all vulnerable in the first sense, there are also different sources and levels of vulnerability depending on (...) concrete social circumstances. Recently, Michael Hauskeller argued about a fundamental incompatibility between transhumanism and vulnerability. He understands vulnerability as an existential category, linked to woundability and mortality. This idea is akin to ontological vulnerability, but it does not notice some important features of social vulnerability. On the other side, transhumanism is a complex and non-homogeneous movement. Here we distinguish between a strong and a weak version of transhumanism. We will propose that the salience of vulnerability is only diminished in the radical one, while a moderate version can reconcile vulnerability with human enhancement. Thus, vulnerability, a concept that has recently gained much importance as an anthropological category in contemporary ethics, is not necessarily at odds with any transhumanist project. (shrink)
The Alligator's Child was full of 'satiable curtiosity. One day while rummaging in a trunk in the lumber room he came across a photograph of his father wearing an aardvark uniform and standing by a large ant hill. All excitement, he rushed to his father and breathlessly said, ‘Father, I didn't know that you had been an aardvark! What is it like to be an aardvark?’.
We present an approach to understanding the origin of inertia involving the electromagnetic component of the quantum vacuum and propose this as a step toward an alternative to Mach's principle. Preliminary analysis of the momentum flux of the classical electromagnetic zero-point radiation impinging on accelerated objects as viewed by an inertial observer suggests that the resistance to acceleration attributed to inertia may be at least in part a force of opposition originating in the vacuum. This analysis avoids the ad hoc (...) modeling of particle-field interaction dynamics used previously by Haisch, Rueda, and Puthoff (Phys. Rev. A 49, 678, (1994)) to derive a similar result. This present approach is not dependent upon what happens at the particle point, but on how an external observer assesses the kinematical characteristics of the zero-point radiation impinging on the accelerated object. A relativistic form of the equation of motion results from the present analysis. Its manifestly covariant form yields a simple result that may be interpreted as a contribution to inertial mass. We note that our approach is related by the principle of equivalence to Sakharov's conjecture (Sov. Phys. Dokl. 12, 1040, (1968)) of a connection between Einstein action and the vacuum. The argument presented may thus be construed as a descendant of Sakharov's conjecture by which we attempt to attribute a mass-giving property to the electromagnetic component—and possibly other components—of the vacuum. In this view the physical momentum of an object is related to the radiative momentum flux of the vacuum instantaneously contained in the characteristic proper volume of the object. The interaction process between the accelerated object and the vacuum (akin to absorption or scattering of electromagnetic radiation) appears to generate a physical resistance (reaction force) to acceleration suggestive of what has been historically known as inertia. (shrink)
Jean-Paul Sartre, in describing the realization of his freedom, was often inclined to say mysterious things like ‘I am what I am not’, ‘I am not what I am’ He was therefore plainly contradicting himself, but was this merely a playful literary figure , or was he really being incoherent? By the latter judgment I do not mean to reject his statements entirely ; for I believe there is an intimate link between contradiction and freedom, as I shall explain in (...) this paper. But a minor thing we must first have out of the way is the suggestion that Sartre's language was just a rhetorical trope, designed merely to express some banal platitude in a bemusing way: ‘I am not yet what I will be’, ‘I am no longer what I was’ are sane and sensible, for instance, but cannot be the meant content of Sartre's sayings, since, while they would indeed describe the reform of some character, they would be appropriate only before or after some metamorphosis, not, as Sartre clearly intended, in the midst of some process of riddance and conversion, whether radical or otherwise. Yet, in the turmoil of such a change, ‘I am not what I am’ still, surely, cannot be true, and if that is the case, Sartre must be being inocherent, and therefore, obfuscating and deliberately obscure, and hence, it seems, must properly be rejected by all right and clear thinking men. (shrink)
If “perfectionism” in ethics refers to those normative theories that treat the fulfillment or realization of human nature as central to an account of both goodness and moral obligation, in what sense is “human flourishing” a perfectionist notion? How much of what we take “human flourishing” to signify is the result of our understanding of human nature? Is the content of this concept simply read off an examination of our nature? Is there no place for diversity and individuality? Is the (...) belief that the content of such a normative concept can be determined by an appeal to human nature merely the result of epistemological naiveté? What is the exact character of the connection between human flourishing and human nature? These questions are the ultimate concern of this essay, but to appreciate the answers that will be offered it is necessary to understand what is meant by “human flourishing.” “Human flourishing” is a relatively recent term in ethics. It seems to have developed in the last two decades because the traditional translation of the Greek term eudaimonia as “happiness” failed to communicate clearly that eudaimonia was an objective good, not merely a subjective good. (shrink)
This introduction to mathematical logic starts with propositional calculus and first-order logic. Topics covered include syntax, semantics, soundness, completeness, independence, normal forms, vertical paths through negation normal formulas, compactness, Smullyan's Unifying Principle, natural deduction, cut-elimination, semantic tableaux, Skolemization, Herbrand's Theorem, unification, duality, interpolation, and definability. The last three chapters of the book provide an introduction to type theory (higher-order logic). It is shown how various mathematical concepts can be formalized in this very expressive formal language. This expressive notation facilitates proofs (...) of the classical incompleteness and undecidability theorems which are very elegant and easy to understand. The discussion of semantics makes clear the important distinction between standard and nonstandard models which is so important in understanding puzzling phenomena such as the incompleteness theorems and Skolem's Paradox about countable models of set theory. Some of the numerous exercises require giving formal proofs. A computer program called ETPS which is available from the web facilitates doing and checking such exercises. Audience: This volume will be of interest to mathematicians, computer scientists, and philosophers in universities, as well as to computer scientists in industry who wish to use higher-order logic for hardware and software specification and verification. (shrink)
The paper illustrates how organic chemists dramatically altered their practices in the middle part of the twentieth century through the adoption of analytical instrumentation — such as ultraviolet and infrared absorption spectroscopy and nuclear magnetic resonance spectroscopy — through which the difficult process of structure determination for small molecules became routine. Changes in practice were manifested in two ways: in the use of these instruments in the development of ‘rule-based’ theories; and in an increased focus on synthesis, at the expense (...) of chemical analysis. These rule-based theories took the form of generalizations relating structure to chemical and physical properties, as measured by instrumentation. This ‘Instrumental Revolution’ in organic chemistry was two-fold: encompassing an embrace of new tools that provided unprecedented access to structures, and a new way of thinking about molecules and their reactivity in terms of shape and structure. These practices suggest the possibility of a change in the ontological status of chemical structures, brought about by the regular use of instruments. The career of Robert Burns Woodward provides the central historical examples for the paper. Woodward was an organic chemist at Harvard from 1937 until the time of his death. In 1965, he won the Nobel Prize in Chemistry. (shrink)
The aim of this paper is to set out some of the ontologies amongst which some forms of anti-realism must select. This provides the appropriate setting for presenting an alternative realist ontology. The argument is that the choice between the varieties of anti-realism and realism is inevitably a choice between ontologies.
This volume is a collection of original essays by eminent philosophers written for R. B. Braithwaite's eightieth birthday to celebrate his work and teaching. In one way or another, all the essays reflect his central concern with the impact of science on our beliefs about the world and the responses appropriate to that. Together they testify to the signal importance of his contributions in areas of philosophy bearing on this concern: the philosophy of science, especially of the statistical sciences, theories (...) of belief and of probability, decision theory and games theory. This book, which includes a full bibliography of Professor Braithwaite's work, will interest advanced students and professionals in the fields of philosophy and psychology. (shrink)
In the paper I offer a brief sketch of one of the sources of utilitarianism. Our biological ancestry is a matter of fact that is not altered by the way we describe ourselves. With philosophical theories it is otherwise. Utilitarianism can be described in ways that make it look as if it is as old as moral philosophy – as J. S. Mill thought it was. For my historical purposes, it is more useful to have an account that brings out (...) what is specific about Benthamism and its descendants. Let us try to make do with the following. First, utilitarianism asserts that the fundamental requirement of morality is that we are to maximize good, for everyone and not just for the agent. This basic principle presupposes that it makes sense to think of aggregating goods to make a total, and of comparing amounts of good thus aggregated. Second, the good to be brought about is located in feelings of pleasure, and the evil to be avoided in feelings of pain. These feelings have inherent value or disvalue regardless of how they are caused to exist and regardless of their own consequences. Third, all moral principles can be derived from the requirement that good be maximized. The principles involved in evaluating agents as well as in giving moral direction to action are nothing but applications of the basic principle. (shrink)
O objetivo do estudo foi verificar evidência de validade simultânea para o Desenho da Figura Humana-Escala Sisto. Mais especificamente se o DFH-Escala Sisto diferencia as categorias de interpretação fornecidas pelo manual das Matrizes Progressivas Coloridas de Raven. Participaram 279 crianças do Ens..
Studies in Empirical Philosophy was published in 1962 shortly after Anderson's death and had been prepared by him to include most of his published articles from the Australasian Journal of Philosophy and Psychology. It also includes a couple of articles written especially for the book. It remains the main published source of material on Anderson's systematic philosophy. John Passmore has kindly granted permission for his introduction to be included in this new release. John Anderson (1893-1962) was Challis Professor of Philosophy (...) at the University of Sydney from 1927 until 1958. He is generally regarded as the most important philosopher to have worked in Australia. His students included not only academic philosophers but also important figures in politics, law and journalism. His impact upon Sydney's social and cultural life was enormous. (shrink)
This essay explains the inescapability of moral demands. I deny that the individual has genuine reason to comply with these demands only if she has desires that would be served by doing so. Rather, the learning of moral reasons helps to shape and channel self- and other-interested motivations so as to facilitate and promote social cooperation. This shaping happens through the “embedding” of reasons in the intentional objects of motivational propensities. The dominance of the instrumental conception of reason, according to (...) which reasons must be based in desires of the individual, has made it harder to recognize that reasons shape desires. I attempt to undermine this dominance by arguing that the concept of a self that extends over time is constructed to meet the demands of social cooperation. Prudential reasons to act on behalf of the persisting self's desires are often taken to constitute the paradigm of reasons based on desires of the individual. But such reasons, along with the very concept of the persisting self, are constructed to promote human cooperation and to shape the individual's desires. (shrink)
This skit of Bertrand Russell’s philosophy was originally published in 1918 by Russell’s correspondent friend Jourdain. The introduction explains that the contents purport to be lost papers written by Mr. B*rtr*nd R*ss*ll, a contemporary of Bertrand Russell. This politically humorous volume from the early 20 th Century parodies the writing style of Russell as well as his theories.
According to both deontologists and consequentialists, if there is a reason to promote the general happiness – or to promote any other state of affairs unrelated to one's own projects or self-interest – then the reason must apply to everyone. This view seems almost self-evident; to challenge it is to challenge the way we think of moral reasons. I contend, however, that the view depends on the unwarranted assumption that the only way to restrict the application scope of a reason (...) for action is by restricting it to those agents whose interests or projects are involved in the reason. In fact normative theories may coherently restrict application scopes in other ways. Thus we must take seriously the possibility that the reason to promote the general happiness, although genuine, does not apply to everyone. (shrink)
In a recent examination of the origins of ordinal utility theory in neoclassical economics, Robert D. Cooter and Peter Rappoport argue that the ordinalist revolution of the 1930s, after which most economists abandoned interpersonal utility comparisons as normative and unscientific, constituted neither unambiguous progress in economic science nor the abandonment of normative theorizing, as many economists and historians of economic thought have generally believed. Rather, the widespread acceptance of ordinalism, with its focus on Pareto optimality, simply represented the emergence of (...) a new neoclassical research agenda that, on the one hand, defined economics differently than had the material welfare theorists of the cardinal utility school and, on the other, adopted a positivist methodology in contrast to the less restrictive empiricism of the cardinalists. (shrink)
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