Paul Needham has claimed in several recent papers that Dalton’s chemical atomism was not explanatory. I respond to his criticism of Dalton by arguing that explanation admits of degrees and that under a view that allows for a spectrum of explanatory value, it is possible to see ample worth in Dalton’s atomistic explanations. Furthermore, I argue that even Duhem, who rejected atomism, acknowledged the explanatory worth of Dalton’s atomism.

The covalent bond, a difficult concept to define precisely, plays a central role in chemical predictions, interventions, and explanations. I investigate the structural conception of the covalent bond, which says that bonding is a directional, submolecular region of electron density, located between individual atomic centers and responsible for holding the atoms together. Several approaches to constructing molecular models are considered in order to determine which features of the structural conception of bonding, if any, are robust across these models. Key components (...) of the structural conception are absent in all but the simplest quantum mechanical models of molecular structure, seriously challenging the conception’s viability. †To contact the author, please write to: Department of Philosophy, University of Pennsylvania, 433 Cohen Hall, Philadelphia, PA 19104‐6304; e‐mail: [email protected]. (shrink)

Recent work on Natural Kind Essentialism has taken a deflationary turn. The assumptions about the grounds of essentialist truths concerning natural kinds familiar from the Kripke-Putnam framework are now considered questionable. The source of the problem, however, has not been sufficiently explicated. The paper focuses on the Twin Earth scenario, and it will be demonstrated that the essentialist principle at its core (which I call IDENT)—that necessarily, a sample of a chemical substance, A, is of the same kind as another (...) sample, B, if and only if A and B have the same microstructure—must be re-evaluated. The Twin Earth scenario also assumes the falsity of another essentialist principle (which I call INST): necessarily, there is a 1:1 correlation between (all of ) the chemical properties of a chemical substance and the microstructure of that substance. This assumption will be questioned, and it will be argued that, in fact, the best strategy for defending IDENT is to establish INST. The prospects for Natural Kind Essentialism and microstructural essentialism regarding chemical substances will be assessed with reference to recent work in the philosophy of chemistry. Finally, a weakened form of INST will be presented. (shrink)

Chemists in the late nineteenth century were apt to distinguish the theory of chemical structure they advocated as chemical, as opposed to physical, atomism. The failure on Duhem’s part to consider any such distinction in his critique of atomism might be taken to be a lacuna in his argument. Far from being a weakness in his stance, however, I argue that he had good systematic reasons for not taking such a distinction seriously.

Introduction to Dossier Pierre Duhem’s Philosophy and History of Science.

Pierre Duhem’s (1861-1916) lifelong opposition to 19th century atomic theories of matter traditionally has been attributed to his conventionalist and/or positivist philosophy of science. Relatively recently, the traditional view has been challenged by the new claim that Duhem’s opposition to atomism was due to the precarious state of atomic theories at the beginning of the 20th century. In this paper, I present some of the difficulties with both the traditional and the new interpretation of Duhem’s opposition to atomism, and provide (...) a new framework in which to understand Duhem's rejection of atomic hypotheses. I argue that although not positivist, instrumentalist, or conventionalist, Duhem’s philosophy of physics was not compatible with belief in unobservable atoms and molecules. The key for understanding Duhem’s resistance to atomism during the final phase of his career is the historicist arguments he presented in support of his ideal of physics. (shrink)

Quine, taking the molecular constitution of matter as a paradigmatic example, offers an account of the relation between theory confirmation and ontology. Elsewhere, he deploys a similar ontological methodology to argue for the existence of mathematical objects. Penelope Maddy considers the atomic/molecular theory in more historical detail. She argues that the actual ontological practices of science display a positivistic demand for “direct observation,” and that fulfillment of this demand allows us to distinguish molecules and other physical objects from mathematical abstracta. (...) However, the confirmation of the atomic/molecular theory and the development of scientists’ ontological attitudes towards atoms was more complicated and subtle than even Maddy supposes. The present paper argues that the history of the theory in fact supports neither Quine’s and Maddy’s accounts of scientific ontology. There was no general demand from scientists to “see” atoms before they were reckoned to be real; but neither did the indispensable appearance of atoms in the best theory of chemical combination suffice to convince scientists of their reality. (shrink)

New perspectives on Pierre Duhem’s The aim and structure of physical theory Content Type Journal Article DOI 10.1007/s11016-010-9467-3 Authors Anastasios Brenner, Department of Philosophy, Paul Valéry University-Montpellier III, Route De Mende, 34199 Montpellier cedex 5, France Paul Needham, Department of Philosophy, University of Stockholm, 10691 Stockholm, Sweden David J. Stump, Department of Philosophy, University of San Francisco, 2130 Fulton Street, San Francisco, CA 94117, USA Robert Deltete, Department of Philosophy, Seattle University, 901 12th Avenue, Seattle, WA 98122-1090, USA Journal Metascience (...) Online ISSN 1467-9981 Print ISSN 0815-0796 Journal Volume Volume 20 Journal Issue Volume 20, Number 1. (shrink)