The debate between ontological reductionists and emergentists in chemistry has revolved around quantum mechanics. What Franklin and Seifert (BJPS 2020) add to the long-running dispute is an attention to the measurement problem. They contend that all three realist interpretations of the quantum formalism capable of resolving the measurement problem also obviate any need for chemical emergence. I push their argument further, arguing that the realist interpretations of quantum mechanics actually subvert the basis for reduction as well, by undercutting the idea (...) that fundamental physical particles are actual parts of molecules. With both reduction and traditional synchronic emergence pictures ruled out, the only option for realists about quantum chemistry is strong Thomistic emergence. (shrink)

Philosophers have often debated the truth of microstructural essentialism about chemical substances: whether or not the structure of a chemical substance at the molecular scale is what makes it the substance it is. Oddly they have tended to pursue this debate without identifying what a structure is, and with some confusion and about what a chemical substance is. In this paper I draw on chemistry to rectify those omissions, providing a pluralist account of structure, clarifying what (according to chemistry) a (...) chemical substance is and defending microstructural essentialism, as I understand that position. I then give an account of the existence of composite substances and objects in chemistry, an issue that goes back to Aristotle. (shrink)

This paper offers an interpretation of Aristotle’s treatment of the homoeomerous, or like-parted, bodies. I argue that they are liable to be far more complexly structured than is commonly supposed. While Aristotelian homoeomers have no intrinsic macrostructural properties, they are, in an important class of cases, essentially marked by the presence and absence of microstructural ones. As I show, these microstructural properties allow Aristotle to neatly demarcate the non-elemental homoeomers from the elements. That demarcation, in turn, helps to clarify Aristotle’s (...) conceptions of both homoeomery and what it is to be a bodily element. On Aristotle’s account, I argue, a homoeomerous body, as such, is divisible into at least one part that is the same specific kind as the whole. Elemental bodies are the limiting case. For Aristotle, an elemental body is only divisible into parts that are of the same specific kind as the whole. (shrink)

In this paper a possible interpretative value of Aristotle’s fundamental ontological doctrine of potentiality and actuality is considered in the context of operationally undoubtedly the most successful but interpretatively still controversial theory of modern physics – quantum mechanics – especially regarding understanding the nature of the world, the phenomena of which it describes and predicts so successfully. In particular, beings of the atomic world are interpreted as real potential beings actualized by the measurement process in appropriate experimental arrangement, and the (...) problem of actual beings of the atomic world is considered in the context of Aristotle’s threefold requirement for the priority of actuality over potentiality – in time, definition or knowledge, and substantiality. (shrink)