The design of the bronchial tree has largely been proposed as a model of optimal design from a physical-functional perspective. However, the distributive function of the airway may be more related to a geometrical than a physical problem. The bronchial tree must distribute a three dimensional volume of inspired air on a two dimensional alveolar surface, included in a limited volume. It is thus valid to ask whether an optimal bronchial tree from a physical perspective is also optimum from a (...) geometrical point of view. In this paper we generate a simple geometric model for the branching pattern of the bronchial tree, deducing relationships that permit estimation of the departures from the geometrical optimum of each bifurcation. We also, for comparative purposes, estimate the departures from the physical optimum. From the geometrical assumptions: i) a symmetrical dichotomic fractal design, ii) with minimum volume and iii) maximum dispersion of the terminal points; and several simulations we suggest that the optimality is characterized by a bifurcation angle Θ ∼ 60° and a length reduction scale γ = (1/2)1/3 = 0.7937. We propose distances from the physical and geometrical optimality defined as Euclidean distances from the expected optima. We show how the advanced relationships and the distances can be used to estimate departures from the optimality in bronchographs of four species. We found lower physical and geometrical departures in the distal zone than those of the proximal zones, as well as lower physical than geometrical departures from optimality. (shrink)
In this work we study the suggestive position of some authors who constitute an exception in the history of the philosophy in respect to the interpretation of the agent intellect, the great Aristotle´s discovery: FranciscoCanals, Leonardo Polo and his disciples, because these authors put the agent intellect at the level of “ actus essendi hominis ”.
It is a truism that a market economy cannot function without trust. We must be able to rely on other people to respect our property rights, and on our trading partners to keep their promises. The theory of economics is incomplete unless it can explain why economic agents often trust one another, and why that trust is often repaid. There is a long history of work in economics and philosophy which tries to explain the kinds of reasoning that people use (...) when they engage in practices of trust: this work develops theoriesoftrust. A related tradition in economics, sociology and political science investigates the kinds of social institution that reproduce whatever habits, dispositions or modes of reasoning are involved in acts of trust: this work develops theoriesofsocialcapital. A recurring question in these literatures is whether a society which organizes its economic life through markets is capable of reproducing the trust on which those markets depend. In this paper, we look at these themes in relation to the writings of three eighteenth-century philosopher-economists: David Hume, Adam Smith, and Antonio Genovesi. (shrink)
How can science be brought to connect with experience? This book addresses two of the most challenging problems facing contemporary neurobiology and cognitive science. Firstly, understanding how we unconsciously execute habitual actions as a result of neurological and cognitive processes that are not formal actions of conscious judgment but part of a habitual nexus of systematic self-organization. Secondly, attempting to create an ethics adequate to our present awareness that there is no such thing as a transcendental self, a stable subject (...) or soul. The author combines researches in cognitive science and phenomenology with two representatives of what he calls the 'wisdom traditions': Confucianism and Buddhist epistemology. (shrink)
Interpreters disagree on the origin that Francisco Suárez assigns to political obligation and correlative political subjection. According to some, Suárez, as other social contract theorists, believes that it is the consent of the individuals that causes political obligation. Others, however, claim that for Suárez, political obligation is underived from the individuals' consent which creates the city. In support of this claim they invoke Suárez's view that political power emanates from the city by way of "natural resultancy". I argue that (...) analysis of Suárez's less studied De voto and De iuramento reveals that, for Suárez, consent causes both the city and the citizen's political obligation. Moreover, close inspection of the notion of causation by natural resultancy within Suárez's metaphysics shows that what emanates from the body politic in this fashion is not, as claimed, political subjection and political obligation, but rather the city's right to self-mastership. Because for him political obligation does originate in consent it is not incorrect to regard Suárez as a social contract theorist. (shrink)
The moral enhancement of human beings is a constant theme in the history of humanity. Today, faced with the threats of a new, globalised world, concern over this matter is more pressing. For this reason, the use of biotechnology to make human beings more moral has been considered. However, this approach is dangerous and very controversial. The purpose of this article is to argue that the use of another new technology, AI, would be preferable to achieve this goal. Whilst several (...) proposals have been made on how to use AI for moral enhancement, we present an alternative that we argue to be superior to other proposals that have been developed. (shrink)
We explore the distinctive characteristics of Mexico's society, politics and history that impacted the establishment of genetics in Mexico, as a new disciplinary field that began in the early 20th century and was consolidated and institutionalized in the second half. We identify about three stages in the institutionalization of genetics in Mexico. The first stage can be characterized by Edmundo Taboada, who was the leader of a research program initiated during the Cárdenas government (1934-1940), which was primarily directed towards improving (...) the condition of small Mexican farmers. Taboada is the first Mexican post-graduate investigator in phytotechnology and phytopathology, trained at Cornell University and the University of Minnesota, in 1932 and 1933, respectively. He was the first investigator to teach plant genetics at the National School of Agriculture and wrote the first textbook of general genetics, Genetics Notes, in 1938. Taboada's most important single genetics contribution was the production of "stabilized" corn varieties. The extensive exile of Spanish intellectuals to Mexico, after the end of Spain's Civil War (1936-1939), had a major influence in Mexican science and characterizes the second stage. The three main personalities contributing to Mexican genetics are Federico Bonet de Marco and Bibiano Fernández Osorio Tafall, at the National School of Biological Sciences, and José Luis de la Loma y Oteyza, at the Chapingo Agriculture School. The main contribution of the Spanish exiles to the introduction of genetics in Mexico concerned teaching. They introduced in several universities genetics as a distinctive discipline within the biology curriculum and wrote genetics text books and manuals. The third stage is identified with Alfonso León de Garay, who founded the Genetics and Radiobiology Program in 1960 within the National Commission of Nuclear Energy, which had been founded in 1956. The Genetics and Radiobiology Program rapidly became a disciplinary program, for it embraced research, teaching, and training of academics and technicians. The Mexican Genetics Society, created by de Garay in 1966, and the development of strains and cultures for genetics research were important activities. One of de Garay's key requirements was the compulsory training of the Program's scientists for at least one or two years in the best universities of the United States and Europe. De Garay's role in the development of Mexican genetics was fundamental. His broad vision encompassed the practice of genetics in all its manifestations. (shrink)
Many studies have attempted to assess the relative effects of different vectors of a disease on animal populations. To this end, three measures have been proposed: Vectorial efficiency, Vectorial capacity and recently Vectorial effectiveness (or Vectorial impact). In this study we relate these measures to derive some of their properties emphasising in the vectorial impact for its importance in both, population performance of parasites and the proportion of the prevalence of one parasite due to a given vector. We applied the (...) quantitative expressions advanced in this study to a simple Chilean example with one parasite (Trypanosoma cruzi), two vectors (Triatoma infestans and Mepraia spinolai) and one animal population (humans: Chagas's disease). (shrink)
The extreme sexual size dimorphism in spiders has motivated studies for many years. In many species the male can be very small relative to the female. There are several hypotheses trying to explain this fact, most of them emphasizing the role of energy in determining spider size. The aim of this paper is to review the role of energy in sexual size dimorphism of spiders, even for those spiders that do not necessarily live in high foliage, using physical and allometric (...) principles. Here we propose that the cost of transport or equivalently energy expenditure and the speed are traits under selection pressure in male spiders, favoring those of smaller size to reduce travel costs. The morphology of the spiders responds to these selective forces depending upon the lifestyle of the spiders. Climbing and bridging spiders must overcome the force of gravity. If bridging allows faster dispersal, small males would have a selective advantage by enjoying more mating opportunities. In wandering spiders with low population density and as a consequence few male–male interactions, high speed and low energy expenditure or cost of transport should be favored by natural selection. Pendulum mechanics show the advantages of long legs in spiders and their relationship with high speed, even in climbing and bridging spiders. Thus small size, compensated by long legs should be the expected morphology for a fast and mobile male spider. (shrink)
My purpose in this article is to propose an explicitly naturalized account of the experience of present nowness on the basis of two complementary sources: phenomenological analysis and cognitive neuroscience. What I mean by naturalization, and the role cognitive neuroscience plays will become clear as the paper unfolds, but the main intention is to use the consciousness of present time as a study case for the phenomenological framework presented by Depraz in this Special Issue.
It is necessarily true that water is H2O, but it is a contingent fact that there is any water at all. Water therefore seems ill suited to ground the necessary truth that water is H2O. One view traditionally attributed to Scotus and Henry of Ghent was that while water is contingent, the essence of water is necessary; hence, the essence of water can ground the so-called eternal truth that water is H2O. Francisco Suárez rejects this view on the grounds (...) that it contradicts the Christian doctrine of creation, according to which everything other than God was contingently created in time. Suárez’s own view of the eternal truths has proven elusive to commentators, but I argue that Suárez ultimately endorses a version of the view he rejects: essences ground the eternal truths. But this raises several puzzles: how is Suárez’s view distinct from the views traditionally ascribed to Scotus and Henry? How does Suárez’s view escape the argument from creation, which Suárez raises against his opponents? I argue that Suárez distinguishes between his view and his opponents’ view by saying that essences have “extrinsic being,” whereas his opponents claim that essences have “intrinsic being.” The distinction between intrinsic and extrinsic being has not received much attention, but I argue that it marks an important fault line in scholastic thinking about the ontological status of non-existents. I argue that the notion of extrinsic being can be explicated in terms of ontological pluralism and grounding. The notion of extrinsic being helps differentiate Suárez’s view from his Scotistic and Henrician opponents, and it allows Suárez to respond to the creation argument he raises against his opponents. On my reading, Suárez’s solution to the problem of eternal truths turns out to be both highly original and philosophically satisfying. (shrink)
This paper responds to the issues raised by D. Chalmers by offering a research direction which is quite radical because of the way in which methodological principles are linked to scientific studies of consciousness. Neuro-phenomenology is the name I use here to designate a quest to marry modern cognitive science and a disciplined approach to human experience, thereby placing myself in the lineage of the continental tradition of Phenomenology. My claim is that the so-called hard problem that animates these Special (...) Issues can only be addressed productively by gathering a research community armed with new pragmatic tools for the development of a science of consciousness. I will claim that no piecemeal empirical correlates, nor purely theoretical principles, will really help us at this stage. We need to turn to a systematic exploration of the only link between mind and consciousness that seems both obvious and natural: the structure of human experience itself. In what follows I motivate my choice by briefly examining the current debate about consciousness at the light of Chalmer’s hard problem. Next, I outline the phenomenological strategy. Finally I conclude by discussing some of the main difficulties and consequences of this strategy. (shrink)
This paper represents a step in the analysis of the key, but much-neglected role of affect and emotions as the originary source of the living present, as a foundational dimension of the moment-to-moment emergence of consciousness. In a more general sense, we may express the question in the following terms: there seems to be a growing consensus from various sources -- philosophical, empirical and clinical -- that emotions cannot be seen as a mere 'coloration' of the cognitive agent, understood as (...) a formal or un-affected self, but are immanent and inextricable from every mental act. How can this be borne out, beyond just announcing it? Specifically, what is the role of affect-emotion in the self-movement of the flow, of the. (shrink)
The ultimate source of explanation in biology is the principle of natural selection. Natural selection means differential reproduction of genes and gene combinations. It is a mechanistic process which accounts for the existence in living organisms of end-directed structures and processes. It is argued that teleological explanations in biology are not only acceptable but indeed indispensable. There are at least three categories of biological phenomena where teleological explanations are appropriate.
Presenting an ardent defence of Charles Darwin's theory of evolution, this book offers a clear and comprehensive exposition of Darwin's thinking. Michael Ruse brings the story up to date, examining the origins of life, the fossil record, and the mechanism of natural selection. Rival theories are explored, from punctuated equilibrium to human evolution . The philosophical and religious implications of Darwinism are discussed, including a discussion of Creationism and its modern day offshoot, Intelligent Design Theory. Ruse draws upon the most (...) recent discoveries, writing with a minimum of jargon in order to appeal to all readers, from professional biologists to those concerned that Darwinism is a naturalistic religion that is forced on school children despite their own Christian convictions. Openly revealing his own beliefs, Ruse presents readers with all the information and critical tools they need to make an informed decision on evolutionary theory. (shrink)
In discussing the works of 16th-century theorists Francisco de Vitoria and Alberico Gentili, this article examines how two different conceptions of a global legal community affect the legal character of the international order and the obligatory force of international law. For Vitoria the legal bindingness of ius gentium necessarily presupposes an integrated character of the global commonwealth that leads him to as it were ascribe legal personality to the global community as a whole. But then its legal status and (...) its consequences have to be clarified. For Gentili on the other hand, sovereign states in their plurality are the pinnacle of the legal order(s). His model of a globally valid ius gentium then oscillates between being analogous to private law, depending on individual acceptance by states and being natural law, appearing in a certain sense as a form rather of morality than of law. (shrink)
A common objection to the use of balancing tests in human rights adjudication is that it is not possible to perform a quantitative comparison between gains and losses for rights or the public good by means only of rational criteria. Here I provide a general account of the incommensurability objection, with the aim of making explicit its scope, and of dispelling some common misconceptions surrounding it. Relying on this account, I engage with recent defences of balancing against the incommensurability objection.