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)

Acidity provides an interesting example of an everyday concept that developed fully into a scientific one; it is one of the oldest concepts in chemistry and remains an important one. However, up to now there has been no unity to it. Currently two standard theoretical definitions coexist ; the standard laboratory measure of acidity, namely the pH, only corresponds directly to the Br⊘nsted-Lowry concept. The lasting identity of the acidity concept in modern chemistry is based on the persistence of the (...) quotidian concept. This is suggestive for considerations of other scientific concepts. (shrink)

Summary This paper presents a case study that contributes to the current debate among historians of chemistry concerning the role and influence of pedagogy in science. Recently, Bernadette Bensaude-Vincent and her colleagues concluded that in nineteenth-century France, ?textbooks played an important role in discipline building and in creating theories?.1 Developing this idea further, this paper examines the dissemination of knowledge through face-to-face chemical lectures, showing that the influence of pedagogical strategy on theoretical content of the science is far from negligible. (...) The pedagogy of William Cullen was essentially responsible for the prevalence of the doctrine of affinity in British chemistry from the 1760s onwards. Cullen used his affinity theory as a pedagogical tool that to a large extent defined his discipline, and the pedagogical pyramid that he headed similarly ensured that the doctrine would remain at the heart of British chemistry. From a pedagogical tool, the doctrine of affinity was transformed over time into a chemical tool, offering British chemists a disciplinary common ground that both set and reinforced the boundaries to their discipline. 1A. Garcia-Belmar, B. Bensaude-Vincent and J.R. Bertomeu-Sánchez, ?The Power of Didactic Writings: French Chemistry Textbooks of the Nineteenth Century?, in Pedagogy and the Practice of Science: Historical and Contemporary Perspectives, edited by D. Kaiser (Cambridge, MA, 2005), 243. (shrink)

I will trace the little known prehistory and parts of the better known history of CO2 by investigating some of the names it has been given from Antiquity to the present day. In Antiquity, the words pneuma or spiritus letalis designated both a supernatural force and an exhalation that emanated from certain caves. We will see how CO2 gradually came to be regarded as something natural, a gas and then substance.

Chemistry is a science of analysis and synthesis. This simple statement characterizes chemistry as an art that breaks down the ‘nature out there’ and puts it back together in a form convenient to our use. It hides the fact that chemical substances are products of the analytic and synthetic methods invented at particular places and times in history. Objects of chemical inquiry are not a random collection of natural and artificial substances but are constituted by the stable laboratory procedures that (...) shape chemical worlds. Recent concession to the historical contingency of chemical theories falls short of acknowledging this material contingency of chemical realities. To the latter end, this paper highlights how French chemists consolidated the analytic-synthetic ideal of chemical species by making their evolving analytic methods compatible to each other through a series of theoretical moments and thereby stabilized their objects of inquiry, theory domains and disciplinary terrain. Stabilizing chemical substances has always required normalizing the methods of identifying them and a comprehensive classification that naturalizes them. (shrink)