Reseña de la obra de Rodríguez González, Mariano: _Filosofía de la Mente_. Madrid: Ediciones Complutense, 2021, pp. 287.

En este trabajo se pretende revisar la controversia que Popper mantuvo con la teoríadarwiniana de la evolución. Se señala la presencia de nociones y ejemplos tomados deldarwinismo ya en los escritos de los años 30, el cuestionamento del evolucionismo al hiloda refutación del historicismo durante los cuarenta y los posteriores intentos por rehabilitarsu estatuto científico a partir de la década de los 60. Esta secuencia permite plantear que, sibien Popper trató de mostrar que su pensamiento social y político se funda (...) principalmenteen la epistemología, cabe considerar si son más bien sus valores sociales y políticos los queestablecen el carácter y los límites de su proyecto epistemológico, así como del resto de supensamiento. Se sugiere que el deseo de refutar el pretendido estatus científico de la teoríamarxista pudo ser la razón que lo determinaría a cuestionar el darwinismo que, por otraparte, siempre estuvo dispuesto a aceptar. (shrink)

Dentro de la sociología francesa actual, Gilles Lipovetsky se ha convertido de forma paulatina en uno de los sociólogos con mayor proyección internacional, con sus finos análisis sobre las sociedades postmodernas. En este artículo se plantea una revisión crítica de las principales líneas argumentativas que expone el autor francés. El objetivo es el de reflexionar sobre las limitaciones de su aproximación a los conceptos de postmodernidad, hipermodernidad, y consumo.

This paper examines undergraduate business students' perception of corporate social responsibility in cases in which they have not attended any specific course either dealing with CSR or providing training in ethics. A survey was conducted of 535 Spanish business students as future managers. The results show that the stakeholders' perspective deserves a huge attention for those students considering what the keys of business success are. Significant differences in perception were nevertheless identified when a multifactorial analysis was undertaken. Female students are (...) more concerned about CSR issues. The maximization of value for shareholders is less valued by second- and third-year students than by first-year ones. The findings point to a number of important orientations for the future development of university curriculum. (shrink)

Fundamento: El Plan D de la carrera de Estomatología concibe la existencia de una disciplina principal integradora denominada Estomatología Integral, sobre la base de la concepción de interdisciplinariedad y la mayor flexibilización curricular. Objetivo: Realizar una valoración de la asignatura Atención Integral a la Familia II del plan D de la carrera de Estomatología. Métodos: Se realizó un estudio descriptivo transversal en la Facultad de Estomatología de la Universidad de Ciencias Médicas de Camaguey en Mayo 2015, mediante el análisis documental (...) del plan de estudio D y programa de la disciplina integradora, se exploraron criterios de profesores sobre las potencialidades y limitaciones del diseño curricular. Fueron encuestados directivos del proceso docente y profesores de experiencia. Resultados: En los objetivos instructivos de la carrera no se incluye el referente a la Estomatología Legal, pero está recogido en los problemas de salud, en los modos de actuación del modelo del profesional y en los objetivos del 4to año donde se imparte la asignatura. La formulación del primer objetivo instructivo se considera muy general y amplia. Conclusiones: La ubicación de la asignatura es correcta en la malla curricular. Tiene suficientes horas de Educación en el trabajo y es adecuada la proporción de las actividades teóricas; como aspectos negativos contenido resalta la extensión y amplitud del tercer tema y la escasez y pobre actualización de la literatura docente. Introduction: The Curriculum D of Dentistry career conceives the existence of a main integrated discipline called Comprehensive Dentistry on the basis of the multi-disciplinary conception and the most curricular flexibility. Objective: To make an assessment of the subject Family Comprehensive Attention II Curriculum D of Dentistry career. Methods: A descriptive-transverse study was performed in the Dentistry Faculty of the University of Medical Sciences in May 2015 by means of the documentary analysis of the Curriculum D and the syllabus of the comprehensive discipline, different professors´criteria were explored about the potencialities and limitations of the curricular design. The board of directors of the teaching process as well as experienced professors were interviewed. Results: The instructive objectives of the career are not included in Legal Dentistry but they are taken into account when dealing with heath problems, the ways of behavior of the future professional and the objectives of the 4th-year subject. The formulation of the first instructive objective is considered very general and broad. Conclusions: Its location is correct bearing in mind the curricular design. It contains enough hours for the practice at dental clinics and a correct gradation of the theoretical activities, a very broad and lengthy content in topic III as well as scarce and not updated literature were the negative aspects. (shrink)

Dentro de la sociología francesa actual, Gilles Lipovetsky se ha convertido de forma paulatina en uno de los sociólogos con mayor proyección internacional, con sus finos análisis sobre las sociedades postmodernas. En este artículo se plantea una revisión crítica de las principales líneas argumentativas que expone el autor francés. El objetivo es el de reflexionar sobre las limitaciones de su aproximación a los conceptos de postmodernidad, hipermodernidad, y consumo.

In recent years, the term populism has become indeed popular. Among its variants, a very particular one stands out. It is the so-called managerial populism, in which prominent businessmen have entered the arena of politics with a program focused on the regeneration of economic and social life. Donald Trump, perhaps, has been the most outstanding example. In this article, our aim is to analyze this phenomenon of managerial populism, addressing a number of issues. Firstly, we will discuss the emergence of (...) a certain type of charismatic leadership in business or management ideologies as a development that largely precedes the consolidation of these figures in the political scene; the implications of these ideologies in the political and social sphere; and the importance of the forms of discursive use of the concept of people in these popular discourses. (shrink)

Este artículo describe la evolución de los recursos de acogimiento residencial en el contexto del Estado Español, comenzando por la época de la dictadura franquista hasta la actualidad. Explicamos cómo fueron financiados los recursos mediante los cuales se daba ayuda a las personas menores de edad en situación de vulnerabilidad. Asimismo, se analiza la evolución de dichos recursos hasta hoy en día. Estos recursos se han ido profesionalizando a lo largo del tiempo y, hoy en día, dan respuestas especificas a (...) diferentes necesidades de los niños, niñas, adolescentes y jóvenes del territorio histórico de Bizkaia.Recibido. (shrink)

Plantea la educación en línea nuevos problemas a la Ciencia de la Educación, que tiene un carácter dual: es Ciencia Social y Ciencia de lo Artificial. La mediación de la Tecnología refuerza la dimensión artificial de la Ciencia de la Educación, que se configura como una Ciencia de Diseño. Esto revierte en la vertiente interna y la dimensión externa de la actividad educativa. Este artículo ofrece un análisis filosófico-metodológico de la Educación mediada por la Tecnología. Lo hace desde el marco (...) teórico de las Ciencias de lo Artificial, lo que aporta novedad: por un lado, este enfoque es poco habitual; y, por otro, la Filosofía de la Ciencia apenas ha prestado atención a la Ciencia de la Educación. Dentro de este marco temático, para resolver problemas en los procesos de enseñanza mediados por la Tecnología, se contextualizan los diseños educativos como diseños científicos. Después se analizan sus límites para atender las distintas dimensiones de la Educación. (shrink)

This article tells the empirical story of women from seven villages of Kwale, the most southeastern county in the Coast Province of Kenya that borders with Tanzania—Lunga Lunga, Godo, Perani, Umoja, Maasailand, Mpakani and Jirani—as they searched for community health, equity, gender equality and peace on their own terms. This article shows that creative health initiatives can be successfully used as mechanisms for peace building. Since 2010, the Nikumbuke-Health by All Means projects from the University of Madison-Wisconsin in the United (...) States, have trained 57 health promoters and 32 female actors on disease prevention and health promotion that have outreached approximately 120,000 inhabitants around the county enhancing unity in diversity, and breaking down the walls of ethnic hostilities and prejudice. Because of its low cost and high effectivity, the United Nations awarded N-HbAM[1] the 2013 Public Service Award as a model of best practice in gender, community development and sustainable wellbeing. [1] In 2013, at the time of the UNPS Award the projects were still called Nikumbuke-Health by Motorbike. The name was changed in 2018 as the projects broadened in scope and geographical location. (shrink)

La mujer todavía tiene numerosas barreras para poder acceder al Deporte (Pérez-Ugena, 2020). Esto se debe, tal y como indica Monforte y Úbeda-Colomer (2019) a que los estereotipos de género siguen existiendo en nuestra sociedad. El objetivo de estudio fue analizar los estereotipos de género en la Actividad Física y el Deporte en 51 adolescentes, utilizando para ello variables sociodemográficas y el instrumento de CEGAFD (Granda et al., 2018). Los resultados muestran que, en la mayoría de los ejemplos, se toma (...) como referente el sexo masculino, destacando también, diferencias significativas en la variable de Estereotipos de Género en el Deporte. (shrink)

Background The COVID-19 pandemic has influenced the approach to the health-disease system, raising the question about the principles of bioethics present in physician–patient relations. The principles while widely accepted may not be sufficient for a comprehensive ethical analysis. Therefore, the aim of this study was to explore the perception of these principles and the physician–patient relationship during a hospital stay through a qualitative approach. Method Sixteen semi-structured interviews took place to know the patients’ perception during their 2020 hospitalization for COVID-19. (...) The data was analyzed through the constant comparison method, creating categories and comparing them. In the end, seven categories were established and were grouped in three: bioethical principles (dignity, charity, vulnerability, autonomy), doctor-patient relationship (participant commitment, informed consent, health staff-patient relationship) and the experience of the disease (illness, the role of the family). Results The research found that most patients described a positive experience, with the feeling of having been well cared for with no sense of discrimination or injustice done. The majority also reported that their autonomy was respected in the treatment decisions. The evaluation of these attitudes is an area of opportunity, especially when the patients' vulnerability is at risk. Conclusions The ethics of virtue offers a better reflection of how human beings manifest themselves by emphasizing the development of virtuous character and behaviors that allow them to realize their values in life. Authorized by the Research Ethics Committee with registration: DI/18/105-B/3/308. (shrink)

Assessing physical fitness has emerged as a proxy of the health status of children and adolescents and therefore as relevant from a public health point of view. DAFIS is a project included in Plan Galicia Saudable of the regional government of Galicia. DAFIS consists of an on-line software devoted to record the results of a standard physical fitness protocol carried out as a part of the physical education curriculum. The aims of this study were: to obtain normative values of physical (...) fitness of the Galician school population evaluated in the DAFIS project, and to identify a reduced number of components and tests able to capture a significant amount of the variability in the physical fitness of children and adolescents. From an initial sample of 27784 records, 15287 cases were considered after filtering. Generalized Additive Models for Location, Scale and Shape were used for obtaining percentile curves and tables for each sex. Furthermore, a principal components analysis was performed, selecting the number of components by applying the Kaiser’s rule and selecting a subset of variables considering the correlation between each variable and the components. Percentile curves and normative values are reported for each test and sex. Physical fitness was better in boys than in girls throughout age groups, except for flexibility that was consistently higher in girls. Two main components were detected throughout age groups: the first one representing body composition and partially cardiorespiratory fitness and the second one muscular fitness. For boys and girls, waist to height ratio had the highest correlations with the first component in four out of six age groups. The highest correlation with the second component, was most frequently observed for the handgrip test both in boys and girls. This study provides evidence about the utility of school community actions like DAFIS aimed to track the health-related fitness of children and adolescents. The results suggest that fat mass distribution and muscular performance concentrate a high proportion physical fitness variance. (shrink)

The assembly of products or components by operators in industries is a complex task with recurring problems. In these processes, operators often make errors that can lead to defective products. Therefore, they need to be inspected later to verify their correct assembly. The main problems are caused by several reasons including high employee turnover, lack of experience in manufacturing specific products or confusion in interpreting instructions to assemble similar components. In this paper, a novel structured language aimed to describe the (...) required actions to manufacture a product in industrial assembly environments is presented. The main contribution is to provide a formal language to feed automatic systems that can verify through visual control whether the actions performed by the operator are carried out following the standard described by this language. In general, the use of this formal language will allow to minimize the negative impact of errors during assembly and to reduce waste in many forms in the industry. (shrink)

Psychological flexibility is a key concept of acceptation and commitment therapy. This factor has been linked with psychological wellbeing and associated factors, such as quality of life, in cancer patients. These and other positive results of acceptation and commitment therapy in cancer patients found in previous research could be enhanced by using mhealth tools. A three-arm randomized superiority clinical trial, with a pre-post-follow-up repeated measures intergroup design with a 1:1:1 allocation ratio is proposed. A hundred and twenty cancer patients will (...) be randomly assigned to one of the following interventions: face-to-face ACT + mobile application, face-to-face ACT, and Waitlist control group. The primary expected outcome is to observe significant improvements in psychological flexibility acceptance and action questionnaire- II in the face-to-face ACT + app group, after comparing baseline and post-treatment scores, and the scores will remain stable in the two assessment points, 3 and 6 months after the intervention. Secondary expected outcomes are significant increasing scores in quality of life and post-traumatic-growth, and significant decreasing scores in anxiety and depression, insomnia and fatigue at the same assessment points. Also, it is expected that the scores of this group will be higher than the scores of the face-to-face ACT group and the waitlist control group. This study aims to assess the efficacy of a combined intervention for psychological flexibility and associated symptoms in cancer patients. The results of this protocol may help to consider the use of acceptation and commitment therapy and mhealth applications in cancer settings as a valid therapeutic choice.Clinical Trial Registration[www.ClinicalTrials.gov], identifier [NCT05126823]. (shrink)

The topos of jews’ blindness, recurrent in adversos iudaeos literature, embodies in the image of blindfold Synagoga in medieval visual arts. The first part of this paper focuses on its integration in different contexts of medieval Spanish art. Diferent, but not less interesting, is the way caecitatis iudeorum is illustrated in some illuminated manuscripts of Breviari d’Amor by Matfre Ermengaud and Fortalitium Fidei by Alonso de Espina, also subject of study throughout these pages.

Los caminos espinosos en la construcción del conocimiento son un cometido al que solo el animal humano se ha enfrentado. El uso de un lenguaje proposicional le ha permitido iniciar construcciones racionales, que dan origen a las teorías más complejas en pos de comprender los enigmas del universo, y con ello iniciar la separación tajante entre episteme y doxa. Los discursos más enmarañados, rígidos y rigurosos convocan a científicos y epistemólogos. Enunciados con términos que, en ocasiones, se tornan oscuros y (...) poco comprensibles a quienes inician sus procesos formativos en el campo de la ciencia y la filosofía. Tal vez por ello se presenta un contraste actual en la enseñanza de las ciencias: por una parte, quienes apuestan por enseñar la rigidez de los enunciados científicos, y la conciben bajo un lenguaje unívoco, neutral y de carácter lógico-deductivo; y por otro lado, quienes la humanizan desde dinámicas móviles y cimentaciones semánticas artificiosas, las cuales, se alejan —como lo expone Héctor Palma en el prólogo del libro Bestiario epistemológico. Metáforas zoomórficas y de otras entidades en la enseñanza de las ciencias y la epistemología– de los enunciados depurados y se valen de nuevos discursos desde el ámbito literario, en los que abundan las metáforas. (shrink)

The objective of this work is to establish a relationship between the cutting time in rocks, determining a speed and the point load strength index test, Is, to characterize the rock in terms of resistance and avoid sending samples to laboratories. As a first stage, on andesite samples, 5 x 5 x 10 cm test tubes were made. After the elaboration they were subjected to cutting, using an electric floor cutter and the time was evaluated. This cut was made in (...) a transversal way and two parts were obtained, one of them with dimensions 5 x 5 x 5 cm, approximately. In a third stage, the point load strength test was carried out in a press built for this purpose. Finally, the cutting speeds were correlated with the point load test values and only when rock samples do not pigeonhole on the proposed relationship, send them to the laboratory. Keywords: Mining fortification, uniaxial compressive strength, rock cutting, point load strength test index. References [1]P. Feijoo, R. Aucay, D. Ordoñez, "Aplicación del esclerómetro para la determinación de resistencia a compresión de rocas", presentado en el IV Congreso Internacional de Minería y Metalúrgia, Varadero, Cuba, 2018. [2]P. Feijoo y M. Román, «Correlación entre la Deformación y la Resistencia a la Compresión de rocas», uct, vol. 23, n.º 91, p. 6, may. 2019. [3]P. Feijoo, A. Bravo, N. Escandón, "Aplicación “UDAFORMIN” para la determinación del tipo de fortificación minera", presentado en el XII Congreso Iberoamericano de Computación para el Desarrollo, San Salvador, El Salvador, 2019. [4]P. Feijoo y C. Iñiguez, «Corte en las Rocas y su Relación con la Resistencia a Comprensión Simple», RISTI, n.º E 30, p. 59-67, jun. 2020. [5]P. Feijoo y J. Padrón, «La Resistividad de Rocas y su Relación con la Resistencia a Comprensión Simple en Mina», UCT, vol. 24, n.º 99, pp. 61-67, abr. 2020. [6]M. González. El terreno. Ediciones UPC. Barcelona. España, 2001. [7]E. Besoain. Mineralogía de Suelos. Turrialba: Instituto Interamericano de Ciencias Agrícolas de la OEA, 1970. [8]P. Feijoo, A. Flores, B. Feijoo, "The Concept of the Granulometric Area and Its Relation with the Resistance to the Simple Compression of Rocks", presentado en la 7th International Engineering, Sciences and Technology Conference, Panamá, Panamá, 2019, pp. 52-56, doi: 10.1109/IESTEC46403.2019.00018. [9]F. Blyth. Geología para Ingenieros. Cecsa. México D. F. México, 2003. [10] E. Tarbuck & F. Lutgens. Ciencias de la Tierra: Una introducción a la Geología Física. Pearson. Madrid. España, 2005. [11]L. Suarez del Rio, A. Rodríguez, L. Calleja, V. Ruiz de Argandoña, «El corte de rocas ornamentales con discos diamantados: influencia de los factores propios del sistema de corte», CSIC, vol. 48, n.º 250, pp. 53-59, abr-mayjun 1998. [12]Universidad Politécnica de Madrid. Explotaciones de Roca Ornamental. Diseño de explotaciones y selección de maquinaria y equipos. UPM. Madrid. España, 2007. [13]Catalog, Covington,. LAPIDARY & GLASS MACHINERY, USA. Retrieved from https://covington-engineering.com/content/pdf/Covington-Catalog.pdf. [14]D. Burbano, T. García, «Estimación empírica de la resistencia a compresión simple a partir del ensayo de carga puntual en rocas anisótropas », FIGEMPA, vol.1, n.º 2, pp. 13-16, dic. 2016. [15]P. Ramírez, L. de la Cuadra, R. Lain, E. Grigalbo. Mecánica de rocas aplicada a la minería metálica subterránea. Instituto Geológico Minero. Madrid. España, 1984. [16]P. Cordero, "Manual de prácticas de laboratorio de Mecánica de Rocas " tesis, Universidad Nacional Autónoma de México, México D.F., México, 2019. [17]L. González de Vallejo, M. Ferrer. Manual de campo para la descripción y caracterización de macizos rocosos en afloramientos. Instituto Geológico y Minero de España. Madrid. España, 2007. [18]P. Pohjanpera, T. Wanne, E., Johansson. Point Load Test Results From Olkiluoto Area Borehole Cores. Posiva. Finlandia, 2005. [19]P. Ramírez, L. Alejano. Mecánica de rocas: fundamentos e ingeniería de taludes. Universidad Politécnica de Madrid. Madrid. España, 2004. [20]M. Navarrete, W. Martínez, E. Alonso, C. Lara, A. Bedolla, H. Chávez, D. Delgado, J. Arteaga. «Caracterización de propiedades físico-mecánicas de rocas ígneas utilizadas en obras de infraestructura», ALCONPANT, vol. 3, n.º 2, pp. 133-143, ago. 2013. [21]P. Feijoo, "Manual de mecánica de rocas y estabilidad de túneles y taludes" tesis, Universidad del Azuay, Cuenca, Ecuador, 1997. (shrink)

El objetivo de este artículo es mostrar la estructura del procedimiento que conducía a los textos romanceados y las características que debían tener los originales. Nos acercamos a este tipo de texto, documentos de importancia excepcional tanto para historiadores como para arabistas, hispanistas o traductores, como ejemplo altamente formalizado de traducción cotidiana en el medio escrito, llevada a cabo por traductores especializados o romanceadores. Tanto el proceso en sí mismo como los romanceamientos siguen unas fases perfectamente delimitadas que vamos a (...) señalar. Para la realización de este trabajo hemos utilizado un pleito de límites del siglo XVI, inédito, donde se incluyen dos romanceamientos de los célebres granadinos Juan Rodríguez y Alonso del Castillo. (shrink)

Gonzalo Rodriguez-Pereyra presents an original study of the place and role of the Identity of Indiscernibles in Leibniz's philosophy. The Principle of the Identity of Indiscernibles rules out numerically distinct but perfectly similar things; Leibniz derived it from more basic principles and used it to establish important philosophical theses. Rodriguez-Pereyra aims to establish what Leibniz meant by the Principle of Identity of Indiscernibles, what his arguments for and from it were, and to assess those arguments and Leibniz's claims about the (...) Principle of Identity of Indiscernibles. He argues that Leibniz had a very strong version of the principle, according to which no possibilia are intrinsically perfectly similar, where this excludes things that differ in magnitude alone. The book discusses Leibniz's arguments for the Identity of Indiscernibles in the Meditation on the Principle of the Individual, the Discourse on Metaphysics, Notationes Generales, Primary Truths, the letter to Casati of 1689, the correspondence with Clarke, as well as the use of the Identity of Indiscernibles in Leibniz's arguments against the Cartesian conception of the material world, atoms, absolute space and time, the Lockean conception of the mind as a tabula rasa, and freedom of indifference. Rodriguez-Pereyra argues that the Identity of Indiscernibles was a central but inessential principle of Leibniz's philosophy. (shrink)

Shared intention normally leads to joint action. It does this, it is commonly said, only because it is a characteristically stable phenomenon, a phenomenon that tends to persist from the time it is formed until the time it is fulfilled. However, the issue of what the stability of shared intention comes down to remains largely undertheorized. My aim in this paper is to remedy this shortcoming. I argue that shared intention is a source of moral and epistemic reasons, that responsiveness (...) to such reasons on the part of each individual reinforces her own relevant attitudes, and that this enhances the stability of the shared intention as a whole. We thus discover an important self-reinforcing and stability-enhancing mechanism at the heart of shared intention and action. It follows from this proposal that the psychological commitment that an individual exhibits in joint action is normally a function not only of her own participatory intention, as often maintained, but also of her endorsement of the reasons created by her group’s shared intention to so act. (shrink)

El científico cree en el mesianismo de la razón. Sus esquemas de experiencia establecen una relación de dominio sobre la realidad, y suponen que no existe más paradigma de experiencia que el de las ciencias positivas. Gabriel Marcel elabora un concepto más amplio de experiencia. Existe una experiencia de sentido, que se sirve de un lenguaje no objetivista, unívoco, sino abierto al contacto personal y a realidades más profundas y significativas. Frente al pathos de la demostrabilidad -dogma de la razón (...) práctica científica- Marcel descubre los diferentes niveles de experiencia en el hombre, ninguno de los cuales ha de convertirse en dictatorial. Hay la experiencia de lo irreductible. En definitiva, la verdad no posee primariamente un estatuto abstracto ni teórico, sino que es un acontecimiento. (shrink)

Este trabajo de reflexión e investigación va a la fuente misma del pensamiento político kantiano, para mostrar cómo su concepción republicana se funda en lo que él llama el uso reflexionante de la razón. Para ello, se ha dividido en tres partes: en la primera se señala cómo el pensamiento político kantiano no se funda en el uso teórico ni práctico de la razón, sino en su uso reflexionante, al mismo tiempo que se señalan sus características. En la segunda se (...) desarrolla el pensamiento filosófico político kantiano, teniendo como eje articulador su idea de republicanismo de un pueblo de demonios. Y, finalmente, en la tercera, se muestra cómo, a partir de su concepción reflexionante, puede ser pensada una acción política en el mundo contemporáneo, insinuando su oposición a todo pensamiento revolucionario, dogmático tradicionalista o moralista, que no considere los límites “estructurales” propios de la capacidad moral particular de los seres humanos. (shrink)

In addition to opening a fertile field for inquiry in analytical social epistemology, Miranda Fricker’s work has provided powerful conceptual tools that merge descriptive capacity and political potency. For this reason, over the last fifteen years, the conceptual repertoire introduced by the author has been well received in both academic and political arenas. At times, the concepts of both testimonial and hermeneutical injustice acquire excessive dimensions in the literature, and this undermines, on the one hand, their analytical precision and, on (...) the other, their usefulness. In this paper I argue against Fricker’s structural parallelism thesis and defend an independent treatment of each of these concepts. On this basis, to counteract the hyperinflation of the concept of hermeneutic injustice, I proceed with an exercise of conceptual precision. To this end, I identify the conditions that make hermeneutic injustice both unjust and hermeneutic. Finally, I present theoretical and practical reasons to encourage the rigorous use of these concepts. (shrink)