Despite decades of research and thought on the meaning and identification of revolutions in science, there is no generally accepted definition for this concept. This paper presents 13 different characteristics that have been used by philosophers and historians of science to characterize revolutions in science, in general, and in chemistry, in particular. These 13 characteristics were clustered into six independent factors. Suggestions are provided as to the use of these characteristics and factors to evaluate historical events as to their possible (...) categorization as revolutions in chemistry. Challenges to the goal of creating a consensus definition of “revolutions in science” are also presented in this publication. (shrink)

We provide a detailed history of the concepts of atomic number and isotopy before the discovery of protons and neutrons that draws attention to the role of evolving interplays of multiple aims and criteria in chemical and physical research. Focusing on research by Frederick Soddy and Ernest Rutherford, we show that, in the context of differentiating disciplinary projects, the adoption of a complex and shifting concept of elemental identity and the ordering role of the periodic table led to a relatively (...) coherent notion of atomic number. Subsequent attention to valency, still neglected in the secondary literature, and to nuclear charge led to a decoupling of the concepts of elemental identity and weight and allowed for a coherent concept of isotopy. This concept received motivation from empirical investigations on the decomposition series of radioelements and their unstable chemical identity. A new model of chemical order was the result of an ongoing collaboration between chemical and physical research projects with evolving aims and standards. After key concepts were considered resolved and their territories were clarified, chemistry and physics resumed autonomous projects, yet remained bound by newly accepted explanatory relations. It is an episode of scientific collaboration and partial integration without simple, wholesale gestalt switches or chemical revolutions. (shrink)

I respond to Scerri’s recent reply to my claim that there was a scientific revolution in chemistry in the early twentieth Century. I grant, as Scerri insists, that there are significant continuities through the change about which we are arguing. That is so in all scientific revolutions. But I argue that the changes were such that they constitute a Kuhnian revolution, not in the classic sense of The Structure of Scientific Revolutions, but in the sense of Kuhn’s mature theory, developed (...) in the 1980s and early 1990s. (shrink)

This undergraduate textbook introduces some fundamental issues in philosophy of science for students of philosophy and science students. The book is divided into two parts. Part 1 deals with knowledge and values. Chap. 1 presents the classical conception of knowledge as initiated by the ancient Greeks and elaborated during the development of science, introducing the central concepts of truth, belief and justification. Aspects of the quest for objectivity are taken up in the following two chapters. Moral issues are broached in (...) Chap. 4, which discusses some aspects of the use and abuse of science, taking up the responsibilities of scientists in properly conducting their business and decision-makers in their concerns with the import of science for society. Part 2 contrasts the view of scientific progress as the rejecting of old hypotheses and theories and replacing them with new ones, represented by Karl Popper, with the conception of progress as accumulating knowledge, saving as much as possible from older theories, represented by Pierre Duhem. A concluding chapter defends the natural attitude of taking the theories of modern science to be literally true, i.e. realism, in the face of arguments drawn partly from the history of scientific progress in criticism of this stance. (shrink)

The exploration of chemical periodicity over the past 250 years led to the development of the Periodic System of Elements and demonstrates the value of vague ideas that ignored early scientific anomalies and instead allowed for extended periods of normal science where new methodologies and concepts are developed. The basic chemical element provides this exploration with direction and explanation and has shown to be a central and historically adaptable concept for a theory of matter far from the reductionist frontier. This (...) is explored in the histories of Prout’s hypothesis, Döbereiner Triads, element inversions necessary when ordering chemical elements by atomic weights, and van den Broeck’s ad-hoc proposal to switch to nuclear charges instead. The development of more accurate methods to determine atomic weights, Rayleigh and Ramsey’s gas separation and analytical techniques, Moseley’s X-ray spectroscopy to identify chemical elements, and more recent accelerator-based cold fusion methods to create new elements at the end of the Periodic Table point to the importance of methodological development complementing conceptual advances. I propose to frame the crossover from physics to chemistry not as a loss of accuracy and precision but as an increased application of vague concepts such as similarity which permit classification. This approach provides epistemic flexibility to adapt to scientific anomalies and the continued growth of chemical compound space and rejects the Procrustean philosophy of reductionist physics. Furthermore, it establishes chemistry with its explanatory and operational autonomy epitomized by the periodic system of elements as a gateway to other experimental sciences. (shrink)

A critique of LaPorte's views on chemical kinds, like jade and ruby, is presented. More positively, a new slant is provided on the question of whether elements are natural kinds. This is carried out by appeal to the dual nature of elements, a topic that has been debated in the philosophy of chemistry but not in the natural kinds literature. It is claimed that the abstract notion of elements, as opposed to their being simple substances, is relevant to the Kripke–Putnam (...) approach to natural kinds and to some criticisms that have been raised against it, although I do not support the K–P account. The proposed view avoids the traditional microstructuralist approach to natural kinds. The article also addresses the question of whether natural kinds concern metaphysical or epistemological considerations. Recent attempts by chemists to modify the periodic table are brought to bear on the question of classification and consequently on whether the identification of elements is interest dependent. (shrink)

In his account of scientific revolutions, Thomas Kuhn suggests that after a revolutionary change of theory, it is as if scientists are working in a different world. In this paper, we aim to show that the notion of world change is insightful. We contrast the reporting of the discovery of neon in 1898 with the discovery of hafnium in 1923. The one discovery was made when elements were identified by their atomic weight; the other discovery was made after scientists came (...) to classify elements by their atomic number. By considering two instances of the reporting of the discovery of a new chemical element 25 years apart, we argue that it becomes clear how chemists can be said to have been responding to different worlds as a result of the change in the concept of a chemical element. They saw, did, and reported different things as they conducted their research on the new chemical elements. (shrink)