En 1956, se introdujo el término de inteligencia artificial (IA) para referirse a una tecnología que es capaz de emular las operaciones cognoscitivas del ser humano mediante el uso de sistemas computacionales y programas informáticos, con el fin de ayudar a la toma de decisiones en distintas áreas de conocimiento.Sin embargo, se ha llegado a cuestionar si debe emplearse el calificativo de inteligencia a esos usos de la tecnología digital. También, se ha generado preocupación sobre sus implicaciones éticas, debido a (...) que la inteligencia artificial consiste en sistemas no autónomos que no son capaces de actos libres y responsables, lo cual exige que sean guiados por personas. Por tanto, el presente trabajo tiene como objeto presentar algunos fundamentos de la filosofía realista de santo Tomás de Aquino que nos permitan hacer una valoración de la inteligencia artificial. (shrink)

Si observamos con detenimiento la realidad, veremos que no hay efecto sin fin, de modo que la subordinación de todos los agentes se lleva a cabo en función de los fines para los que están dispuestos, pues todo lo que se realiza, se realiza en vista de un fin. Sin embargo, el materialismo racionalista, empirista e idealista, sólo acepta que hay un bien útil o deleitable y rechaza el bien honesto y al negar la finalidad en la que lo imperfecto (...) se subordina a lo perfecto, no sólo se excluye a Dios, sino que, una vez que una persona muere, no hay más que la descomposición del cuerpo quedando descartada la trascendencia. Por otra parte, la negación del principio de finalidad también afecta el primer principio práctico que es la sindéresis con lo que se compromete el orden moral. Esa es la razón por la que vemos importante recuperar el pensamiento de santo Tomás de Aquino y algunas de sus implicaciones en torno al principio de finalidad, ya que, al presentar la universalidad, evidencia e importancia del principio de finalidad, santo Tomás demuestra la apertura del hombre a la trascendencia y el orden moral que se requiere para alcanzarla. (shrink)

Este ensayo revisa, desde la perspectiva de Berger y Luckmann, un encuentro con la otredad que se vuelve factor determinante en la socialización secundaria de Germán, personaje principal de la novela Fruta verde, donde él es rara avis que no aceptó como naturales ni perpetuas las condiciones imperantes del medio que lo veía adentrarse en la adolescencia rumbo a la madurez.

El presente artículo analiza el desarrollo de las Elecciones Municipales Complementarias 2019 en doce distritos en los que se declaró la nulidad del proceso luego de las Elecciones Regionales y Municipales 2018 en el Perú. De acuerdo a la legislación electoral de este país, la declaración de nulidad de un proceso es competencia del Jurado Nacional de Elecciones y se produce debido a dos causales. En el primer caso, once distritos tuvieron que repetir su proceso electoral debido a que el (...) conteo de votos nulos y en blanco, sumado o separado, superaron los 2/3 del número de votos emitidos. Mientras que, en un solo distrito se declaró la nulidad del proceso debido a la inasistencia de más del 50% de votantes producto de la no instalación de las mesas de sufragio. Más allá del argumento jurídico sobre la nulidad de los procesos, es necesario considerar un factor como la violencia electoral que estuvo presente en todos estos distritos. El proceso electoral en estas circunscripciones fue interrumpido debido al descontento de los ciudadanos con el desarrollo del proceso y las amenazas de violencia electoral. Es así como, es posible incluir a esta variable como un factor explicativo para la interrupción de los procesos electorales. Así, la presente investigación desarrolla un análisis cualitativo, en base a la información recopilada por la Oficina Nacional de Procesos Electorales. Este estudio hace especial énfasis en las dinámicas propias de la gestión electoral en distritos con alta probabilidad de sufrir conflictos electorales y describe la forma en que se interrumpieron las elecciones subnacionales en estas circunscripciones. (shrink)

En este ensayo se revisará el legado de Francisco de Quevedo y Villegas en algunos autores hispanoamericanos cuya característica común es un dominio superlativo del español: Jorge Luis Borges, Octavio Paz, Juan José Arreola y, por último, en un gran escritor de literatura y crítica que abre una veta para valorar la obra de Quevedo, la cual no fue explorada por los anteriores: José Pascual Buxó.

Art and science is an area of research that has strengthened recently, mainly due to the impact of interdisciplinary work. At the same time, approaches between the humanities and the sciences have succeeded in re-signifying traditional views towards critical positions such as postcolonialism, especially in the colonially so-called “Global South”. In this paper, we want to review the case of the work of the Mexican artist Octavio Ocampo through works that present the case of biological and cultural evolution. From (...) this, we want to reflect on the public perception of science in Mexico, the tensions between social and natural sciences, and the urgent need to strengthen the postcolonial discourse in scientific practice. (shrink)

Conceptual engineering is the method for assessing and improving our representational devices. On its ‘broad-spectrum’ version, it is expected to be appropriately applicable to any of our representation-involving cognitive activities, with major consequences for our whole cognitive life. This paper is about the theoretical foundations of conceptual engineering thus characterised. With a view to ensuring the actionability of conceptual engineering as a broad-spectrum method, it addresses the issue of how best to construe the subject matter of conceptual engineering and successively (...) defends the theses that conceptual engineering should be: (i) About concepts, (ii) psychologically theorised, (iii) as multiply realised functional kinds. Thereby, I claim to theoretically secure and justify the maximum scope, flexibility, and impact for the method of conceptual engineering on our representational devices in our whole cognitive life—in other words, a broad-spectrum version of conceptual engineering. (shrink)

The artificial intelligence models with machine learning that exhibit the best predictive accuracy, and therefore, the most powerful ones, are, paradoxically, those with the most opaque black-box architectures. At the same time, the unstoppable computerization of advanced industrial societies demands the use of these machines in a growing number of domains. The conjunction of both phenomena gives rise to a control problem on AI that in this paper we analyze by dividing the issue into two. First, we carry out an (...) epistemological examination of the AI’s opacity in light of the latest techniques to remedy it. And second, we evaluate the rationality of delegating tasks in opaque agents. (shrink)

In this article, we put forward a new strategy for teaching the concept of energy. In the first section, we discuss how the concept is currently treated in educational programmes at primary and secondary level (taking the case of France), the learning difficulties that arise as well as the main teaching strategies presented in science education literature. In the second section, we argue that due to the complexity of the concept of energy, rethinking how it is taught should involve teacher (...) training specifically developed for the concept. In our view, Epistemology and the History of Science and Technology (EHST) is the best method for a full understanding of the concept of energy and should thus be included in the teacher training programme. In the third section, we provide a general framework for a teacher training programme on energy, based on the history and epistemology of the concept and structured on the following three questions: ‘What is the origin of the concept of energy?’, ‘What is energy?’ and ‘What purpose does the concept of energy serve?’. (shrink)

La pena natural es una situación paradójica que se puede presentar cuando el autor de un delito, al cometerlo o a causa de éste, ha sufrido un daño igual o mayor al que padecería si el juez de la causa le aplicara la pena estatal prevista para tal conducta. Se da con frecuencia al juzgar ciertos accidentes viales, cuando el acusado ya carga el peso de ser quien, por imprudencia, mató a su pareja o familiar cercano, por ejemplo. Pero ¿en (...) qué situaciones y cómo cabe recurrir a la pena natural? En esta investigación, Manuel Serrano explora las diversas aristas y posturas en pugna que atraviesan este tema, donde se cruzan cuestiones como la idea de la “culpa compensada”, la prohibición de aplicar castigo doble por un mismo hecho (non bis in idem) y la clemencia judicial. El autor desmonta la estructura conceptual de la pena natural, estudia jurisprudencia argentina y recorre producciones teóricas de juristas que se han preocupado por este asunto complejo, profundo y poco abordado del derecho penal. (shrink)

The aim of this paper is to give a systematic account of the so-called “measurement problem” in the frame of the standard interpretation of quantum mechanics. It is argued that there is not one but five distinct formulations of this problem. Each of them depends on what is assumed to be a “satisfactory” description of the measurement process in the frame of the standard interpretation. Moreover, the paper points out that each of these formulations refers not to a unique problem, (...) but to a set of sub-problems. (shrink)

The problem of divine attributes was one of the most intensely debated topics in the 17-18th century Irish philosophy. Simply put, the problem revolves around the ontological question (i) whether human and divine attributes differ in degree or in kind, and the semantical (ii) how we ought to describe these divine attributes by means of our human language. While there was a consensus that analogies play a key role in solving the semantical problem there was a controversy about the kind (...) of speech they allow for. Especially, it was contested if using analogies for divine predication allows for a separate kind of speech, i.e. allows us to speak neither literally nor metaphorically but analogically. The aim of my paper is to contextualize George Berkeley's position on the problem of divine attributes as developed in § 21 of the IV. Dialogue in Alciphron.More specifically and contrary to what most scholars hold, I argue Berkeley fails to follow Cardinal Cajetan with remarkable closeness. Despite paraphrasing parts of Cajetan's De Nominum Analogia in § 21, the solution Berkeley advances is closer to the position of John Duns Scotus – and hence, ironically, with the position Cajetan aimed to reject. (shrink)

The aim of this paper is to show that quantum mechanics can be interpreted according to a pragmatist approach. The latter consists, first, in giving a pragmatic definition to each term used in microphysics, second, in making explicit the functions any theory must fulfil so as to ensure the success of the research activity in microphysics, and third, in showing that quantum mechanics is the only theory which fulfils exactly these functions.

According to a common belief concerning the Mach-Boltzmann debate on atoms, the new experiments performed in microphysics at the turn of the 19th and 20th centuries confirmed Boltzmann's atomic hypothesis and disproved Mach's anti-atomic view. This paper intends to show that this belief is partially unjustified. Mach's view on atoms consists in fact of different kinds of arguments. While the new experiments in microphysics refute indeed his scientific arguments against the atomic hypothesis, his epistemological arguments are unaffected. In this regard, (...) Mach's epistemological approach remains relevant for today's discussion on the status of the notion of atom. (shrink)

Necessitism about individuals claims that necessarily every individual necessarily exists. An analogous necessitist thesis attributes necessary existence to properties and relations. Both theses have been defended by Williamson. Furthermore, Williamson specifically argues against the hybrid conjunction of first-order contingentism and higher-order necessitism; a combination that would bring about additional drawbacks. I work out a defence of the hybrid combination, including some replies to Williamson’s additional objections. Considerations of ontological parsimony and pre-theoretical intuitions favour the hybrid view over necessitism at all (...) orders. (shrink)

The way digital information technologies work and, more specifically, the possibilities for action that technological devices offer to us affect our processes of political belief formation. In particular, there seems to be a close connection between our digital affordances and the increase of the sort of polarization that threatens the proper functioning of democracy. In this paper, we analyze whether the type of polarization linked to the use of digital technologies, and which endangers the health of public deliberation, has to (...) do with the adoption of beliefs whose contents are increasingly extreme—extremism—or, on the contrary, has more to do with increasing our credence in the core beliefs of our political identity—radicalism. (shrink)

Jean Buridan developed his theory of consequence within a semantical framework compatible with what we now call token-based semantics. In his Treatise on Consequences and Sophismata, Buridan showed...

One of the great dangers of our time is that the cumulative long-term action of smart socio-technical environments engineered to control thought and behavior results in an excessive loss of freedom. In response to this challenge, that we shall call humanity’s socio-technical dilemma, we outline here some fundamental ideas of a political program to control these environments, which is similar to the one proposed by Brett Frischmann and Evan Selinger. It is similar insofar as we share their paternalistic and humanistic (...) approach. But it is different insofar as we claim, first, the duty to admit that it is a version of Sloterdijk’s controversial human zoo; second, the theoretical and practical convenience of identifying the human capabilities to be promoted by these environments with the capabilities necessary for the democratic electorate to comply with the competence principle; and third, the awareness of the probable long-term unsustainability of the program in a context of competition between countries and companies, in spite of which it must be implemented because of its moral superiority. (shrink)

According to the partisan cheerleading view, numerous political disagreements that appear to be genuine are not authentic disputes, because partisans _deliberately_ misreport their beliefs to show support for their parties. Recently, three arguments have been put forth to support this view. First, contemporary democracies are characterized by affective rather than ideological polarization. Second, financial incentives indicate that partisans often deliberately misreport their beliefs to express their attitudes. Third, partisans have inconsistent and unstable political beliefs, so we should not take these (...) attitudes seriously. In this paper, I examine these arguments and present an alternative view, which I call the partisan conviction view. According to it, partisans are not necessarily insincere in their political judgments, and they are in genuine disagreement. (shrink)

Although commitment is one of the attributes of family firms of continuing interest to researchers, they almost always study it from the perspective of the owning family. In the current work, we analyze the commitment of the non-family employees. We propose a model of commitment, with the aim of studying the implications that this variable may have for family businesses. We study both the aspects on the basis of the approaches of Meyer and Allen's three-component model of organizational commitment and (...) stewardship theory. Results show that the identification level of non-family employees positively and significantly influences the profitability and the survival or continuity of familyowned businesses. At the same time that their involvement level positively and significantly influences the survival or continuity of family-owned businesses. (shrink)

Recent years have seen recurring episodes of tension between proponents of freedom of speech and advocates of the disenfranchised. Recent survey research attests to the ideological division in attitudes toward free speech, whereby conservatives report greater support for free speech than progressives do. Intrigued by the question of whether “canceling” is indeed a uniquely progressive tendency, we conducted a vignette-based experiment examining judgments of offensiveness among progressives and conservatives. Contrary to the dominant portrayal of progressives and conservatives, our study documented (...) ideological symmetry in their evaluations of offensive speech. When faced with utterances whose content matters to them, both conservatives and progressives viewed outgroup speakers as more offensive than ingroup speakers. A second contribution of this chapter is to provide a deeper understanding of the cognitive mechanism implicated in evaluating outgroup speech as more offensive than ingroup speech. Our results suggest that perception of offensiveness is mediated by ascriptions of intent: we tend to attribute negative intent to the speaker whenever we deem their utterances to be offensive, even against the explicitly stated speaker’s background attitudes. (shrink)

Economics students and economists have—grosso modo—a bad societal reputation. This is, roughly speaking, the provocative result of the majority of empirical studies on economic education. On average, economists and economics students behave in a more self-interested way than others; they are more prone to deviate from the moral good; they tend to free-ride more often and invest less in public goods games; they are more corrupt and less honest in lost letterexperiments, less cooperative in solidarity games, and accept less and (...) keep more in ultimatum bargaining games. In short: they seem to behave more in accordance with the predictions of the rational or self-interest model of standard economics, the Homo oeconomicus model. What might be the reasons that the degree of anti-social and uncooperative behavior is on average significantly more pronounced among economics students compared to other student groups? Can these empirical findings be explained by the self-selection effect and/or the indoctrination effect? What are the implications of these empirical results for economic ethics and economic education? Which roles do the economics curriculum and economic textbooks play? Do they have any effect on everyday behavior? Is the way economics is taught at (business) schools, colleges and universities co-responsible for the considerable behavioral differences? And what can be done in order to reverse these trends and to foster other-regarding preferences and pro-social behavior? The paper analyzes these and other questions with the help of experimental economics, behavioral economics and neuroeconomics. It also draws on recent findings of brain physiology research in general and neuroplasticity in particular. (shrink)

We describe the Catholic natural law tradition by examining its origins in the medieval penitentials, the papal decretals, the writings of Thomas Aquinas, and seventeenth century casuistry. Catholic natural law emerges as a flexible ethic that conceives of human nature as rational and as oriented to certain basic goods that ought to be pursued and whose pursuit is made possible by the virtues. We then identify four approaches to natural law that have evolved within the United States during the twentieth (...) century, including the traditionalist, proportionalist, right reason, and historicist approaches. The normative implications of these approaches are discussed in relation to ethical issues in the tobacco industry, ITT under Geneen, the marketing of pharmaceuticals, affirmative action, and bribery. It is argued that Alasdair MacIntyre is correct in claiming that the natural law tradition is superior to the liberal ethics of modern deontology and utilitarianism. (shrink)

Las herramientas teóricas destinadas a señalar las injusticias que sufren ciertos grupos socialmente oprimidos pueden acabar siendo utilizadas con propósitos completamente opuestos a los iniciales. Modificar el alcance de una herramienta teórica no es necesariamente problemático: la popularización de un concepto abre las puertas a que se utilice estratégicamente para diferentes fines. La tesis que defendemos en este artículo es que algunos personajes públicos cultivan una imagen particular de sí mismos que parece satisfacer los requisitos de la noción de injusticia (...) testimonial y utilizan esta situación como medio para obtener beneficio político de ella. Más concretamente, estos personajes públicos se benefician de esta condición para generar situaciones de desacuerdos cruzados, que están estrechamente relacionados con el aumento de la polarización. (shrink)

According to a common belief concerning the Mach-Boltzmann debate on atoms, the new experiments performed in microphysics at the turn of the 19th and 20th centuries confirmed Boltzmann’s atomic hypothesis and disproved Mach’s anti-atomic view. This paper intends to show that this belief is partially unjustified. Mach’s view on atoms consists in fact of different kinds of arguments. While the new experiments in microphysics refute indeed his scientific arguments against the atomic hypothesis, his epistemological arguments are unaffected. In this regard, (...) Mach’s epistemological approach remains relevant for today’s discussion on the status of the notion of atom. (shrink)

Various international authorities have insisted on the importance of ethical learning in higher education for would-be professionals, including students of Business Administration. As the process of creating the European Higher Education Area gathers pace, first steps have been taken to explicitly incorporate ethics in the common European Qualifications Framework. However, the authors of this study show how in the course of the EQF development process, the consideration given to ethical qualifications has been curtailed and subjected to serious limitations. In this (...) article, the authors review the historical development and the main elements of the EQF. Then, they analyze the gradual elimination of ethics within the EQF. Finally, they highlight the implications of this gradual elimination and propose avenues for further research. (shrink)

Examino Acerca del cielo (De caelo) I 2 con el fin de mostrar allí la presencia de la demostración científica. Este desarrollo pretende aportar nueva evidencia en favor de la no discrepancia entre teoría y praxis científica en Aristóteles (Barnes, 1969) y de relativizar la interpretación de que el método real y únicamente usado es la dialéctica (cuyo antecedente se remonta a Owen, 1980). Además, siguiendo la propuesta hermenéutica de Gotthelf (1987) y Detel (1993 y 1997), mostraré de qué modo (...) se utiliza la demostración científica en la prueba de la existencia del cuerpo simple o éter. Ofreceré también una reconstrucción de las pruebas mediante la elaboración de un esquema que abarque el conjunto de las deducciones. Estos últimos desarrollos constituyen el aporte más novedoso del presente artículo. I examine On the Heavens (DC) 12 in order to show there the presence of scientific demonstration. This development tries to contribute new evidence in favor of the not discrepancy between theory and scientific practice in Aristotle (Barnes, 1969) and to make the interpretation that method real and solely used is dialectic relative (whose precedent goes back to Owen, 1980). In addition, following the hermeneutic proposal of Gotthelf (1987) and Detel (1993 and 1997), I will show how scientific demonstration is used in the proof of simple body (ether) existence. I will offer also a reconstruction of the proof by means of the elaboration of a scheme that includes the set of deductions. The latter developments constitute the most new contribution of the present paper. (shrink)

Mereological universalists and nihilists disagree on the conditions for composition. In this paper, we show how this debate is a function of one’s chosen semantics for plural quantifiers. Debating mereologists have failed to appreciate this point because of the complexity of the debate and extraneous theoretical commitments. We eliminate this by framing the debate between universalists and nihilists in a formal model where these two theses about composition are contradictory. The examination of the two theories in the model brings clarity (...) to a debate in which opponents frequently talk past one another. With the two views stated precisely, our investigation reveals the dependence of the mereologists’ ontological commitments on the semantics of plural quantifiers. Though we discuss the debate with respect to a simplified and idealized model, the insights provided will make more complex debates on composition more productive and deflationist criticisms of the debate less substantial. (shrink)

En Acerca del cielo I se encuentran cuatro pruebas fundamentales de la cosmología aristotélica, a saber: la prueba de la existencia del éter, la prueba de la finitud del universo, la prueba de su unicidad y la prueba de su ingenerabilidad e incorruptibilidad. Ofrecemos una reconstrucción parcial del conjunto de estas cuatro pruebas para poner en evidencia que ellas utilizan un grupo semejante de premisas y definiciones. En efecto, nuestro propósito es mostrar que dicho conjunto de pruebas utiliza los mismos (...) principios y, de este modo, que en una reconstrucción axiomática del total de pruebas podemos hallar un número semejante, o incluso mayor, de premisas que de conclusiones. Así, encontramos una forma alternativa para una axiomatización posible en Acerca del cielo de Aristóteles. In On The Heavens there are four crucial proofs of Aristotelian cosmology, namely: proof of the aether existence, proof of the finitude of the universe, proof of its unicity and proof of its ungenerability and its indestructibility. We do a partial reconstruction of the hole of these four proofs to show that they use a similar set of premises and definitions. In fact, our goal is to show that such set of proofs uses the same principles and, in this way, that in a axiomatic reconstruction of the hole of proofs we can find a similar number, even higher, of premises than conclusions. Thus, we find an alternative way for a possible axiomatization on Aristotle's On The Heavens. (shrink)

The emphasis of systems and synthetic biology on quantitative understanding of biological objects and their eventual re-design has raised the question of whether description and construction standards that are commonplace in electric and mechanical engineering are applicable to live systems. The tuning of genetic devices to deliver a given activity is generally context-dependent, thereby undermining the re-usability of parts, and predictability of function, necessary for manufacturing new biological objects. Tolerance and allowance are key aspects of standardization that need to be (...) brought to biological design. These should endow functional building blocks with a pre-specified level of confidence for bespoke biosystems engineering. However, in the absence of more fundamental knowledge, fine-tuning necessarily relies on evolutionary/combinatorial gravitation toward a fixed objective. (shrink)

This article argues that Nietzsche’s transvaluation project refers not to a mere inversion or negation of a set of nihilism-prone, Judeo-Christian values but, instead, to a different conception of what a value is and how it functions. Traditional values function within a standard logical framework and claim legitimacy and “bindingness” based on exogenous authority with absolute extension. Nietzsche regards this framework as unnecessarily reductive in its attempted exclusion of contradiction and real opposition among competing values. I propose a nonstandard, dialetheic (...) model of valuation that requires a value to be both true and false as well as neither true nor false.In our Europe, life is no longer quite so uncertain, contingent, nonsensical. [...] The power man has achieved now allows a reduction of those means of discipline of which the moral interpretation was the strongest.— KSA 12:5[71]The logic of our conscious thinking is only a crude and facilitated form of the thinking needed by our organism [...] A simultaneity-thinking [ein Zugleichdenken], for example, is needed of which we have hardly an inkling. [...] We are still growing continually, our sense of time and place, etc., is still developing.— KSA 11:34[124]. (shrink)

Uno de los acontecimientos teóricos más importantes, ocurridos en la filosofía política de las últimas décadas, es la reformulación del paradigma republicano. Este neorrepublicanismo pretende hacer frente a la profunda crisis de la democracia liberal (corrupción, insolidaridad, apatía ciudadana, etc.), en nuestra época de predominio neoliberal. En el presente artículo desarrollo principalmente su visión de la ética ciudadana; es decir, la importante idea de que la república necesita formular un cierto bien común y promover la virtud cívica de sus ciudadanos, (...) si aspiramos a una sociedad libre de dominación, más justa y solidaria. (shrink)

RÉSUMÉ : Les attitudes de se sont généralement considérées comme constituant une classe particulière d’attitudes de re. Cet article propose une analyse différente, qui s’appuie sur la notion d’attitude de objecto et qui évite un engagement ontologique envers le sujet. La proposition élabore l’idée de Hintikka d’une logique épistémique dite de seconde génération, qui introduit un marqueur syntaxique permettant d’exprimer des relations d’indépendance entre certaines constantes logiques. De cette sémantique résulte une conception du Moi, dénotation de «je», comme un objet (...) simplement intentionnel. ABSTRACT: De se attitudes are generally regarded as being a proper part of de re attitudes. In this paper an alternative analysis that avoids ontological commitment to the self is proposed, based on the notion of de objecto attitudes. This proposal develops an idea from Hintikka’s second generation epistemic logic, which introduces a syntactic marker expressing independence relations between certain logical constants. According to this semantic account, the Self, as the denotation of ‘I’, is conceived of as a mere intentional object. (shrink)

La noción estándar de axiomática que se atribuye a Aristóteles supone un conjunto de proposiciones básicas a partir del cual se infiere un conjunto numéricamente mayor de proposiciones derivadas. Esto se conoce como parsimonia de los principios. Además, el conocimiento de los principios se reduce a una captación intelectual directa. Se pretende mostrar que tales atribuciones no son correctas para el caso de _Acerca del cielo _I. Se brindan elementos para una alternativa de lo que puede entenderse por axiomatización en (...) Aristóteles. Para ello se trabajara en la reconstrucción de los argumentos de algunos pasajes de _Acerca del cielo _I. (shrink)