Henrique Leitão | University of Lisbon (original) (raw)
Highlights by Henrique Leitão
Edgar Zilsel: Philosopher, Historian, Sociologist, 2022
Despite its heuristic potential, Zilsel’s thesis has been charged with a significant explanatory ... more Despite its heuristic potential, Zilsel’s thesis has been charged with a significant explanatory weakness. The fault lies not in the claim that social barriers separating artisans from scholars in Europe were broken around 1600, but in the explanation of how this came about. Zilsel’s original proposal appears to lack an historically grounded explanation of the modes of interaction between these two diverse social groups. This chapter aims at overcoming this perceived deficiency. We argue not only that such an interaction actually existed, but also that it took place in a socially transformative context in early modern Europe, namely, its maritime expansion. As is well known, the creation of great global empires such as the Portuguese, Spanish, English or Dutch generated a complex and wide-ranging series of events that affected many areas, including science and technology. One of the characteristics of the new modes of scientific production was the collaboration between socially and culturally
separated epistemic communities such as, for example, cosmographers and sea pilots. As we will show, in its first phase, this collaboration was far from fortuitous, but rather forced, structured and promoted by the Crown. The interaction was regulated by a normative apparatus in the form of legislation, rules, and regiments. In addition, this interaction took place in institutions specially created for this purpose. In short, the aim of this chapter is not only to emphasize the relevance of Zilsel’s proposal, but also to illustrate it in detail by bringing to the fore the social mechanisms behind his thesis.
Papers by Henrique Leitão
Confraternitas, Feb 6, 2018
Zenodo (CERN European Organization for Nuclear Research), Jul 7, 2021
Largo Campo Di Filosofare 2001 Isbn 84 607 3613 X Pags 903 914, 2001
Bulletin of Portuguese Japanese Studies, 2000
Journal for The History of Astronomy, 2009
History of Mathematical Sciences, 2008
Manuel Dias’ (1574–1659) Tianwenlüe 天問略 (Epitome of Questions on the Heavens, 1615) is a summary ... more Manuel Dias’ (1574–1659) Tianwenlüe 天問略 (Epitome of Questions on the Heavens, 1615) is a summary of European cosmographical and astronomical knowledge. It is a text in the tradition of commentaries on Sacrobosco’s Sphere but with several important novelties. It is structured as a series of questions and answers, the questions being formulated by a Chinese and the answers given by an European. Also worth noting is the fact that it presents examples and data specifically adapted or calculated for China. But, above all, it is remarkable because it presents for the first time in Chinese a description of Galileo’s telescopic observations. Despite being frequently mentioned by historians of science, this text was never studied in detail and nearly every question related to it — composition, contents, diffusion, reception, etc. — remains to be clarified. In this paper I investigate the background of the composition of this text describing the scientific tradition where it stems from, namely, De sphaera literature in Portugal and in Jesuit schools in the sixteenth and early seven-teenth century and, more specifically, Jesuit’s presentation of Western science in China. The questions that will be treated here are mostly related to the author of the Tianwenlüe, his biography, his scientific competence and the sources he used to prepare the text. One question of direct relevance to the composition of the Tianwenlüe will be inspected in more detail: the spreading of news related to Galileo’s discoveries among Jesuits in the Portuguese Assistancy. Finally, some words will be said on the impact of the book
Physica A: Statistical Mechanics and its Applications, 1992
Quaderns d'història de l'enginyeria, 2010
The Journal of Chemical Physics, 1996
Recent experiments revealed a striking scaling behavior of the low and ultralow interfacial tensi... more Recent experiments revealed a striking scaling behavior of the low and ultralow interfacial tension of microemulsions. A description of this behavior based on the Helfrich elastic free energy, which is symmetric in the principal curvatures c1 and c2, appears to be inconsistent. We show that, within the phenomenological theory of membrane bending elasticity, symmetry breaking between the two principal curvatures seems to be required in order to explain the low, but nonzero, values of the interfacial tension and its temperature dependence. We propose two simple generalizations of the Helfrich free energy which describe the experimental results. The first considers a quadratic elastic free energy and anisotropy in the membrane which breaks the symmetry between the two principal curvatures. In the second, which is applicable to systems with positive saddle-splay rigidities, the symmetry between the two principal curvatures is spontaneously broken by inclusion of higher-order terms in th...
The Journal of Chemical Physics, 1998
We have calculated the structure and the interfacial tension of microemulsions on the phase inver... more We have calculated the structure and the interfacial tension of microemulsions on the phase inversion path, using a single-order parameter Landau theory. We show that the observed scaling behavior of the interfacial tensions [T. Sottmann and R. Strey, J. Chem. Phys. 106, 8606 (1997)] is described by a simple theoretical model based on the assumption that the ratio of the length scales characterizing microemulsions is a universal function of the reduced temperature, on the phase inversion path. This assumption is based on the results of small angle neutron scattering experiments on this series of systems, at the optimal microemulsion temperature [T. Sottman, R. Strey, and S.-H. Chen, J. Chem. Phys. 106, 6483 (1997)] and on the scaling properties of the Landau free energy on the phase inversion path.
Geological Society of America Bulletin, 2011
... Page 9. Comissário Científico HENRIQUE DE SOUSA LEITÃO Coordenação Técnica LÍGIA DE AZEVEDO M... more ... Page 9. Comissário Científico HENRIQUE DE SOUSA LEITÃO Coordenação Técnica LÍGIA DE AZEVEDO MARTINS Estudos HENRIQUE DE SOUSA LEITÃO RAUL ESMERIZ DELERUE ANA CRISTINA SANTANA SILVA LÍGIA DE AZEVEDO MARTINS TERESA AS DUARTE ...
e-Letras com Vida: Revista de Estudos Globais — Humanidades, Ciências e Artes
Edgar Zilsel: Philosopher, Historian, Sociologist, 2022
Despite its heuristic potential, Zilsel’s thesis has been charged with a significant explanatory ... more Despite its heuristic potential, Zilsel’s thesis has been charged with a significant explanatory weakness. The fault lies not in the claim that social barriers separating artisans from scholars in Europe were broken around 1600, but in the explanation of how this came about. Zilsel’s original proposal appears to lack an historically grounded explanation of the modes of interaction between these two diverse social groups. This chapter aims at overcoming this perceived deficiency. We argue not only that such an interaction actually existed, but also that it took place in a socially transformative context in early modern Europe, namely, its maritime expansion. As is well known, the creation of great global empires such as the Portuguese, Spanish, English or Dutch generated a complex and wide-ranging series of events that affected many areas, including science and technology. One of the characteristics of the new modes of scientific production was the collaboration between socially and culturally
separated epistemic communities such as, for example, cosmographers and sea pilots. As we will show, in its first phase, this collaboration was far from fortuitous, but rather forced, structured and promoted by the Crown. The interaction was regulated by a normative apparatus in the form of legislation, rules, and regiments. In addition, this interaction took place in institutions specially created for this purpose. In short, the aim of this chapter is not only to emphasize the relevance of Zilsel’s proposal, but also to illustrate it in detail by bringing to the fore the social mechanisms behind his thesis.
Confraternitas, Feb 6, 2018
Zenodo (CERN European Organization for Nuclear Research), Jul 7, 2021
Largo Campo Di Filosofare 2001 Isbn 84 607 3613 X Pags 903 914, 2001
Bulletin of Portuguese Japanese Studies, 2000
Journal for The History of Astronomy, 2009
History of Mathematical Sciences, 2008
Manuel Dias’ (1574–1659) Tianwenlüe 天問略 (Epitome of Questions on the Heavens, 1615) is a summary ... more Manuel Dias’ (1574–1659) Tianwenlüe 天問略 (Epitome of Questions on the Heavens, 1615) is a summary of European cosmographical and astronomical knowledge. It is a text in the tradition of commentaries on Sacrobosco’s Sphere but with several important novelties. It is structured as a series of questions and answers, the questions being formulated by a Chinese and the answers given by an European. Also worth noting is the fact that it presents examples and data specifically adapted or calculated for China. But, above all, it is remarkable because it presents for the first time in Chinese a description of Galileo’s telescopic observations. Despite being frequently mentioned by historians of science, this text was never studied in detail and nearly every question related to it — composition, contents, diffusion, reception, etc. — remains to be clarified. In this paper I investigate the background of the composition of this text describing the scientific tradition where it stems from, namely, De sphaera literature in Portugal and in Jesuit schools in the sixteenth and early seven-teenth century and, more specifically, Jesuit’s presentation of Western science in China. The questions that will be treated here are mostly related to the author of the Tianwenlüe, his biography, his scientific competence and the sources he used to prepare the text. One question of direct relevance to the composition of the Tianwenlüe will be inspected in more detail: the spreading of news related to Galileo’s discoveries among Jesuits in the Portuguese Assistancy. Finally, some words will be said on the impact of the book
Physica A: Statistical Mechanics and its Applications, 1992
Quaderns d'història de l'enginyeria, 2010
The Journal of Chemical Physics, 1996
Recent experiments revealed a striking scaling behavior of the low and ultralow interfacial tensi... more Recent experiments revealed a striking scaling behavior of the low and ultralow interfacial tension of microemulsions. A description of this behavior based on the Helfrich elastic free energy, which is symmetric in the principal curvatures c1 and c2, appears to be inconsistent. We show that, within the phenomenological theory of membrane bending elasticity, symmetry breaking between the two principal curvatures seems to be required in order to explain the low, but nonzero, values of the interfacial tension and its temperature dependence. We propose two simple generalizations of the Helfrich free energy which describe the experimental results. The first considers a quadratic elastic free energy and anisotropy in the membrane which breaks the symmetry between the two principal curvatures. In the second, which is applicable to systems with positive saddle-splay rigidities, the symmetry between the two principal curvatures is spontaneously broken by inclusion of higher-order terms in th...
The Journal of Chemical Physics, 1998
We have calculated the structure and the interfacial tension of microemulsions on the phase inver... more We have calculated the structure and the interfacial tension of microemulsions on the phase inversion path, using a single-order parameter Landau theory. We show that the observed scaling behavior of the interfacial tensions [T. Sottmann and R. Strey, J. Chem. Phys. 106, 8606 (1997)] is described by a simple theoretical model based on the assumption that the ratio of the length scales characterizing microemulsions is a universal function of the reduced temperature, on the phase inversion path. This assumption is based on the results of small angle neutron scattering experiments on this series of systems, at the optimal microemulsion temperature [T. Sottman, R. Strey, and S.-H. Chen, J. Chem. Phys. 106, 6483 (1997)] and on the scaling properties of the Landau free energy on the phase inversion path.
Geological Society of America Bulletin, 2011
... Page 9. Comissário Científico HENRIQUE DE SOUSA LEITÃO Coordenação Técnica LÍGIA DE AZEVEDO M... more ... Page 9. Comissário Científico HENRIQUE DE SOUSA LEITÃO Coordenação Técnica LÍGIA DE AZEVEDO MARTINS Estudos HENRIQUE DE SOUSA LEITÃO RAUL ESMERIZ DELERUE ANA CRISTINA SANTANA SILVA LÍGIA DE AZEVEDO MARTINS TERESA AS DUARTE ...
e-Letras com Vida: Revista de Estudos Globais — Humanidades, Ciências e Artes
Annals of Science, 2020
The set of essays in this issue of Annals of Science provides a convenient occasion for some brie... more The set of essays in this issue of Annals of Science provides a convenient occasion for some brief reflections on the present state of studies about Inquisition and Science. Although this collectio...
Annemarie JORDAN-GSCHWEND (Centro de História d’Aquém e d’Além-Mar, Lisboa and Switzerland) Shopp... more Annemarie JORDAN-GSCHWEND (Centro de História d’Aquém e d’Além-Mar, Lisboa and Switzerland) Shopping in the Renaissance – Merchants as Cultural Mediators in Spain, Portugal and their Overseas Empires
CIÊNCIA, TECNOLOGIA E MEDICINA NA CONSTRUÇÃO DE PORTUGAL 1 NOVOS HORIZONTES (SÉCS. XV A XVII), 2021
Esta colecção apresenta, em quatro volumes, uma visão original e actual da relevância da ciência,... more Esta colecção apresenta, em quatro volumes, uma visão original e actual da relevância da ciência, da tecnologia e da medicina na construção de Portugal, desde o período medieval até aos nossos dias. Pretende‑se dar a conhecer a um público diversificado a melhor investigação histórica nestas áreas, suprindo o alheamento tradicional da historiografia portuguesa relativamente aos contextos científicos nacionais.
O primeiro volume, Novos Horizontes (Sécs. XV a XVII), revisita temas clássicos e temas menos abordados pelos historiadores, com especial ênfase no desenvolvimento das práticas científicas, tecnológicas e médicas durante a construção do império colonial português.
Biblioteca Nacional de Portugal, 2008
http://clavisbibliothecarum.bn.pt/
Este site constitui um complemento do livro Clavis Bibliothecarum, trabalho de investigação desen... more Este site constitui um complemento do livro Clavis Bibliothecarum, trabalho de investigação desenvolvido por Luana Giurgevich e Henrique Leitão, que constitui o mais completo levantamento até agora efetuado de catálogos e inventários de bibliotecas de instituições religiosas portuguesas.
O objetivo central do site é facilitar o acesso à cópia digital integral dos documentos constantes da obra. Para o efeito, foram já digitalizados os catálogos, inventários e outros documentos afins existentes nas coleções da Biblioteca Nacional de Portugal e da Biblioteca Pública de Évora, os quais serão gradualmente disponibilizados na Biblioteca Nacional Digital ficando simultaneamente disponíveis neste site temático.
Today people everywhere consult maps on phones and mobile devices to find their way around. Centu... more Today people everywhere consult maps on phones and mobile devices to find their way around. Centuries ago navigators began to use nautical charts for similar purposes. How did navigators find their position in the middle of the ocean with no land in sight? How did they use nautical charts? What is, exactly, a nautical chart?
Maps have existed from ancient times in many different cultures. For Europeans, the making of maps, especially nautical charts, underwent a critical transformation in the sixteenth century with the onset of long-distance oceanic navigation. The need to adapt to new situations led to a profound re-shaping of how we viewed the globe. Cartographers developed new types of maps, including some of the map projections still seen today in digital maps and mobile phones.
In this presentation, the audience will join in a sea voyage using techniques of sixteenth-century sailors and understand the remarkable solutions they devised. This will culminate in the explanation of the method used by Gerard Mercator to make his famous cartographic projection which opened the door to modern cartography.
Annemarie JORDAN-GSCHWEND (Centro de História d’Aquém e d’Além-Mar, Lisboa and Switzerland) S... more Annemarie JORDAN-GSCHWEND
(Centro de História d’Aquém e d’Além-Mar, Lisboa and
Switzerland)
Shopping in the Renaissance – Merchants as Cultural Mediators in Spain, Portugal and their Overseas Empires