This paper studies European chemists’ shifting ontologies of materials by comparing the ways in which they classified materials. The focus is on plant materials, their different identities, and the changing ways chemists sorted out and ordered plant materials in the eighteenth and early nineteenth centuries. The main goals of the paper are to follow the development of plant materials from ordinary, everyday materials and commodities in the early eighteenth century to purified carbon compounds and organic substances familiar only to experts (...) in the 1830s, and to reconstruct chemists’ ways of classifying these objects in different practical and intellectual contexts.The study of changes in European chemists’ ways of classifying plant materials over more than a century brings to the foreground a trajectory of ontological shifts that is ‘punctuated’ in the 1750s, the 1790s, and the 1830s. Early eighteenth-century plant materials, which were commodities of the apothecary trade and other arts and crafts, were elevated epistemically as compound components or ‘proximate principles’ of plants in the 1750s, reduced to organic compounds in the 1790s, and replaced by carbon compounds in the 1830s. The last, third transformation of the epistemic constitution of materials and the mode of their classification was accompanied by a deep transformation of the material culture of plant chemistry. After the late 1830s, many of the eighteenth-century vegetable commodities disappeared from chemists’ agenda or were split into different substances individuated and identified in new ways. Coal tar products, and new organic artefacts containing chlorine or bromine, entered the chemical laboratory in the 1820s and became fused with the purified rest of the previous plant and animal substances. The material objects of the new culture of organic chemistry became detached from the materials applied in the extant arts and crafts. It was only in the late 1850s, with the rise of the synthetic dye industry, that a great number of these laboratory substances became involved in industrial production.Keywords: Commodities and scientific objects; Historical ontology; Classification; Plant chemistry; Organic chemistry. (shrink)

Why do some epistemic objects persist despite undergoing serious changes, while others go extinct in similar situations? Scientists have often been careless in deciding which epistemic objects to retain and which ones to eliminate; historians and philosophers of science have been on the whole much too unreflective in accepting the scientists’ decisions in this regard. Through a re-examination of the history of oxygen and phlogiston, I will illustrate the benefits to be gained from challenging and disturbing the commonly accepted continuities (...) and discontinuities in the lives of epistemic objects. I will also outline two key consequences of such re-thinking. First, a fresh view on the (dis)continuities in key epistemic objects is apt to lead to informative revisions in recognized periods and trends in the history of science. Second, recognizing sources of continuity leads to a sympathetic view on extinct objects, which in turn problematizes the common monistic tendency in science and philosophy; this epistemological reorientation allows room for more pluralism in scientific practice itself. (shrink)

Scientific progress remains one of the most significant issues in the philosophy of science today. This is not only because of the intrinsic importance of the topic, but also because of its immense difficulty. In what sense exactly does science makes progress, and how is it that scientists are apparently able to achieve it better than people in other realms of human intellectual endeavour? Neither philosophers nor scientists themselves have been able to answer these questions to general satisfaction.

Ursula Klein has argued that Geoffroy’s table of chemical affinities, published in 1718, marked the emergence of the concepts of chemical compound and chemical combination central to chemistry. In this paper her position is summarised and then modified to render it immune to criticism that has been levelled against it. The essentials of Geoffroy’s chemistry are clarified and adapted to Klein’s picture by way of a detailed comparison of it with Boyle’s corpuscular chemistry that proceeded Geoffroy’s by over half a (...) century. The idea that Geoffroy’s notion of chemical combination marked a significant turning point in the emergence of modern chemistry is defended against the charge that it is Whiggish. (shrink)

Le 31 mai 1703, Étienne-François Geoffroy, qui était alors chimiste à l’Académie royale des sciences, soutint une thèse de médecine présidée par Guy-Crescent Fagon à la Faculté de médecine de Paris sous le titre An medicus, Philosophus Mechanico-Chymicus? S’appuyant notamment sur les travaux de Varignon pour la mécanique et de Homberg pour la chimie, Geoffroy montre que le corps humain n’est pas seulement une merveilleuse machine hydrostatique, mais aussi une machine d’un ordre supérieur, dont seule la chimie peut rendre compte (...) de certaines opérations. Comme Hippocrate lui-même l’aurait suggéré, selon une lecture quelque peu anachronique, le bon médecin, loin de devoir choisir entre mécanique et chimie, doit au contraire user de leur nécessaire complémentarité pour comprendre le fonctionnement du corps humain. (shrink)

The ArgumentJohann von Justi, the foremost literary cameralist of his generation, served as chief police commissioner in Göttingen between 1755 and 1757. While in Göttingen, Justi offered lectures at the university on the “œconomic, police and cameral sciences.” He also arrested vagrants, wrote on chemistry, disciplined unruly students, conducted chemical experiments, supervised the pricing of Göttingen's staple goods, engaged in a public controversy with a prominent Berlin chemist, edited and published a bi-weekly periodical (Göttingische Policey-Amts Nachrichien), and worked with the (...) university's curator to refashion the academic structure of the sciences. Taken together, these various activities reflected his broad vision for social and academic change, a vision with important implications for the form and content of the sciences. Drawing on archival material in Göttingen, on articles from thePolicey-Amts Nachrichten, and on Justi's other cameralist and chemical writings, I use his everyday experiences as a local police official to explore the meaning of his chemical work. I argue that Justi's chemistry was suffused with the cameralist dreams and ambitions of a small-town police commissioner. It is what I call police chemistry. (shrink)

Starting with some illustrative examples, I develop a systematic account of a specific type of experimentation--an experimentation which is not, as in the "standard view", driven by specific theories. It is typically practiced in periods in which no theory or--even more fundamentally--no conceptual framework is readily available. I call it exploratory experimentation and I explicate its systematic guidelines. From the historical examples I argue furthermore that exploratory experimentation may have an immense, but hitherto widely neglected, epistemic significance.

: The increasing attention on experiment in the last two decades has led to important insights into its material, cultural and social dimensions. However, the role of experiment as a tool for generating knowledge has been comparatively poorly studied. What questions are asked in experimental research? How are they treated and eventually resolved? And how do questions, epistemic situations, and experimental activity cohere and shape each other? In my paper, I treat these problems on the basis of detailed studies of (...) research practice. After presenting several cases from the history of electricity—Dufay, Ampère, and Faraday—I discuss a specific type of experiment—the "exploratory experiment"—and analyze how it works in concept formation. I argue that a fuller understanding of experiment can only be achieved by intertwining historical and philosophical perspectives in such a way that the very separation of the two become questioable. (shrink)

In a recent essay review of William R. Newman, Atoms and Alchemy (2006), Ursula Klein defends her position that philosophically informed corpuscularian theories of matter contributed little to the growing knowledge of "reversible reactions" and robust chemical species in the early modern period. Newman responds here by providing further evidence that an experimental, scholastic tradition of alchemy extending well into the Middle Ages had already argued extensively for the persistence of ingredients during processes of "mixture" (e.g. chemical reactions), and that (...) this corpuscular alchemical tradition bore important fruit in the work of early modern chymists such as Daniel Sennert and Robert Boyle. (shrink)

I argue and demonstrate in this essay that interconnected systems of science and technology, or technoscience, existed long before the late nineteenth century, and that eighteenth-century chemistry was such an early form of technoscience. Based on recent historical research on the early development of carbon chemistry from the late 1820s until the 1840s—which revealed that early carbon chemistry was an experimental expert culture that was largely detached from the mundane industrial world—I further examine the question of the internal preconditions within (...) the expert culture of carbon chemistry that contributed to its convergence with the synthetic-dye industry in the late 1850s. I argue that the introduction of new types and techniques of organic-chemical reactions and organic substances in this experimental expert culture, along with the application of chemical formulae as paper tools for modeling reactions as well as the chemical constitution and structure of substances, enabled academic chemists to make specific, novel contributions to chemical technology and industry in the second half of the nineteenth century. (shrink)

The paper examines differences of styles of experimentation in the history of science. It presents arguments for a historization of our historial and philosophical notion of "experimentation," which question the common view that "experimental philosophy" was the only style of experimentation in the eighteenth and early nineteenth centuries. It argues, in particular, that "experimental history" and technological inquiry were accepted styles of academic experimentation at the time. These arguments are corroborated by a careful analysis of a case study, which is (...) embedded in a comparative historical overview. (shrink)

This paper studies the semiotic,epistemological and historical aspects of Berzelianformulas in early nineteenth-century organicchemistry. I argue that Berzelian formulas wereenormously productive `paper tools' for representingchemical reactions of organic substances, and forcreating different pathways of reactions. Moreover, myanalysis of Jean Dumas's application of Berzelianformulas to model the creation of chloral from alcoholand chlorine exemplifies the role played by chemicalformulas in conceptual development (the concept ofsubstitution). Studying the dialectic of chemists'collectively shared goals and tools, I argue thatpaper tools, like laboratory instruments, areresources (...) whose possibilities are not exhausted byscientists' attempts to achieve existing goals, butrather whose applications generate new goals. The term`paper tools' is introduced to emphasize that thepragmatic and syntactic aspects of symbol systems arefully comparable to physical laboratory tools. (shrink)

The main goal of this article is to use the epistemological framework of a specific version of Cognitive Constructivism to address Piaget’s central problem of knowledge construction, namely, the re-equilibration of cognitive structures. The distinctive objective character of this constructivist framework is supported by formal inference methods of Bayesian statistics, and is based on Heinz von Foerster’s fundamental metaphor of objects as tokens for eigen-solutions. This epistemological perspective is illustrated using some episodes in the history of chemistry concerning the definition (...) or identification of chemical elements. Some of von Foerster’s epistemological imperatives provide general guidelines of development and argumentation. (shrink)