Professor Robin Hendry

IAS Fellow, Durham University (October – December 2009)

Robin Hendry is Professor in Philosophy at Durham University. He has published extensively on philosophical issues in chemistry, and their bearing on general issues in the philosophy of science like reductionism and unity in science, natural kinds and classification, and scientific realism.

Hendry took a BSc in Chemistry and the Philosophy of Science at King’s College London. Foundational problems in quantum chemistry prompted him to sign up for a PhD in Philosophy at the London School of Economics, but in the end his thesis mostly concerned scientific methodology, the historical development of quantum theory, and scientific realism. His first lectureship was at the University of Edinburgh, after which he came to Durham in October 1994. Since then his work, supported by fellowships granted by the Leverhulme Trust and the Arts and Humanities Research Council, has focused increasingly on chemistry, a science which, in contrast to physics and biology, has largely been ignored by philosophers. His book The Metaphysics of Chemistry, shortly to be published by Oxford University Press, examines the historical development of chemical taxonomy and nomenclature, explanations in quantum chemistry, and attempts to reduce chemistry to physics.

During his time at the IAS Hendry will be pursuing two lines of research. The first concerns the relationship between ordinary language and scientific research. According to linguists, non-specialist speakers of English apply the word ‘water’ to chemical substances fairly independently of H2O content. This appears to undermine the view, widely accepted among philosophers, that everyday usage picks out a substance, water, that science has discovered empirically to be H2O. Rather, it is argued, the scientific and colloquial usages are relatively independent, reflecting the differing interests of science (which emphasises molecular composition) and everyday life (which emphasises manifest properties). Hendry suspects that ‘ordinary usage’ may involve a number of inconsistent interests and beliefs, and that it is a mistake to expect it to embody coherent kind-membership conditions. He therefore hopes to develop a more nuanced understanding of the relationship between science and ordinary language in which neither scientist nor layperson is treated as Humpty-Dumpty.

The second line of research concerns the nature of the chemical bond, on which Hendry has already published two papers. The bond has its origins in nineteenth-century chemistry, when chemists began to associate structural diagrams with chemical substances to account for the differences between isomers. But twentieth-century chemists found it difficult to locate the classical bond within quantum mechanics. Indeed by the 1950s there came to be a division between those (like Linus Pauling) who thought that structure and bonding are irreducible and indispensible elements of chemical theory, and those (like Charles Coulson), who were more sceptical about whether bonds should have a long-term explanatory role. Hendry plans to extend his work forward in time, investigating recent attempts to recover something like classical bonds from density-functional approaches to molecular quantum mechanics.