Centaurus

Human beings can neither see nor feel magnetism, although its effects can be made manifest to sense experience through experiments. Since antiquity, philosophers have therefore often viewed magnetism as an “occult” force, for whose manifest effects a hidden cause had to be sought. Around 1300, scholars began to address the seemingly occult nature of magnetism not only through experimental investigation but also visually, attempting to represent experimental results in diagrams. Historical research on diagrams has been fairly negligent about the relation between diagrams and scientific practices, including experiments. This paper will try to redress the balance, by focusing on diagrams in manuscripts and printed texts between 1300 and 1700 that were produced in response to magnetic experiments. It will be argued that naturalistic and geometrizing forms of representation were combined in order to render experiments with magnetism understandable, replicable, and meaningful. This resulted in a visual style of diagram that oscillated between the abstract representation of invisible entities or powers and the concrete and performative depiction of actual objects or operations.

Johannes Müller von Königsberg (1436-1476), better known as Regiomontanus, is widely considered as the most influential astronomer and mathematician of 15th-century Europe. He was active as an astrologer and deemed astrology to be the queen of mathematical sciences. Despite this, Regiomontanus's astrological activity has yet to be fully explored. A brief examination of Regiomontanus's manuscripts shows that his astrological interests were accompanied by interests in the arts and in methods of prognostication. This article studies an unconventional astrological-chiromantical text, whose relevance is threefold: a) it sheds new light on Regiomontanus's astrological interests; b) it enriches our knowledge of Regiomontanus's efforts to learn and understand Greek-Regiomontanus transcribed it into his own manuscript during his sojourn in Italy from 1460-1467; and c) it is the sole extant text in the Greek tradition that provides a system for prognostication from the study of a person's hand, the parts of which are considered as being under the domain of planets. The article provides an English translation of Regiomontanus's transcription, alongside a brief commentary, and studies the intellectual and historical context of that production through manuscript analysis.

This article draws attention to several different practices of observation, manipulation, and experimentation with the surface of natural things. Beginning from the observation that the surfaces of natural things invited observation, manipulation, measurement, and re-configuration, with the promise to unveil the knowledge of depths, this article explores how practical knowledge about the surface of things and bodies led to new conceptions of nature and matter as composed of layers, corpuscles, and artificially reproducible solid parts in early modern Europe. This article explores issues of knowledge production, and studies the ways in which material knowledge-making practices contributed to the habits of observing and experimenting with the surface of nature. By discussing three groups of cases in which nature was known by its surface and practice was mixed with theoretical appraisals of matter—surgeons, butchers, and food-cutters; gardeners and agronomists; and physicians—this article argues that “cognitive models” focusing on the description as well as the manipulation of natural surfaces informed both artisanal practices and natural philosophy, bridging the “high” and the “low” in the age of the “scientific revolution.”

Tycho's star catalog enjoyed enormous prestige for centuries due to its accuracy. The entire catalog depends on the coordinates of one single star, Hamal (α Arietis), which explains why Tycho was so scrupulous in determining its coordinates using two different methods applied to more than 50 observations, as he described in his Progymnasmata. One of them proposed an ingenious way of dealing with refraction and parallax, two factors that he knew he could not control. Selecting particular observations, he was able to cancel out the effects of both refraction and parallax. Still, the entire calculation starts from the coordinates of the Sun calculated from his solar model. But Tycho's solar model assumes too large of an eccentricity, producing errors in the predictions of the solar longitude that can reach up to 8'. In this paper, I analyze Tycho's method for calculating the coordinates of α Arietis and explain how the method he proposed unintentionally avoided transferring the error of his solar model to his catalog.

Complexity sciences are one of the most mediatized scientific fields of the last 40 years. While this domain has attracted the attention of many philosophers of science, its normative views have not yet been the object of any systematic study. This article is a contribution to the thin social science literature about complexity sciences and proposes a contribution focused on an analysis of the origins, models, and organization of the Santa Fe Institute (SFI), cradle of the field. The paper defends the thesis that the notion of “complex adaptive systems” bears a project of naturalization of society through numerical and evolutionary lenses by promoting a Darwinian and capitalist view of the economy. At the same time, such a view has been embodied in the very way of functioning of the institute, which was conceived as an agile organization in a competitive environment and which relies on a fundraising philosophy that tends to commodify science. From a theoretical viewpoint, this text is anchored in the field of Science and Technology Studies and particularly in the coproductionist paradigm, which theorizes the dynamic entanglement of science and society. In terms of empirical sources, the article is based on interviews conducted by the author, and on the SFI's scientific publications as well as institutional archives.

This article analyses the relationship between the Belgian government and the national Nuclear Research Centre (SCK CEN) in the renegotiation of the mission and organization of Big Science in Belgium. While the founding decades of nuclear laboratories are often characterized by ever-increasing budgets and the establishment of large infrastructure, I show that downsizing or transforming Big Science demanded a new form of politics on the organization of science. Drawing on archival material, this article will demonstrate how the mission and management of SCK CEN were critically followed by a variety of stakeholders. Furthermore, the Belgian government explicitly aimed to allow corporate principles to guide the reorganization of the research centre by hiring consultants from Arthur Andersen. This episode in the history of nuclear research invites historians of science to reflect upon both the politics of Big Science in an era in which its original principles were fundamentally questioned and the historical development of new norms and expectations attached to this phenomenon.

Green chemistry is a successful new paradigm reshaping the way we think about sustainable chemical synthesis. And yet, its official story, placing the birth of green chemistry in the 1990s within the walls of the Environmental Protection Agency (EPA), is riddled with contradictions and simplifications. Beneath the mainstream narrative, there is another, somewhat forgotten history of numerous attempts to respond to environmental challenges in chemistry with different frameworks and conceptualisations. The frontiers of the concept were far from clear and multiple green chemistries struggled for recognition, both within and beyond the US, with a tremendous amount of theoretical reflection on how to combine sustainability with chemistry conducted in Europe. In Italy, France, and Germany, many scholars anticipated what would become green chemistry in parallel to their American colleagues. And yet, even though the American success story dominated the imaginary of chemists all over the world, these forgotten green-chemistry frameworks developed in the 1990s, be they American or European, present a number of distinct, original features that set them apart. They were not merely imperfect forerunners to a more mature EPA-based concept, but in fact constituted full-fledged alternatives, many of which have a lot to offer to modern practitioners of green chemistry who are unsatisfied with the way the field has evolved. This article tries to recover this forgotten past and to highlight those features that can contribute to contemporary debates on the place of sustainability in chemistry.