Can a bridge be constructed between Whiteheadian process metaphysics and Aristotelian-Scholastic substance metaphysics? I ask this question in the context of physical change, using the chemical transformation of molecules as the quintessential exemplar. While both metaphysical systems describe nature as dynamical and relational, each sees change differently: for process metaphysics, change is constitutive of all actualities, while for substance metaphysics, change is secondary and something that happens to actualities. My analysis concludes that these two systems of thought have fundamental metaphysical (...) differences that do not permit a reconciliation. Rather than reconciliation, what might be possible is the development of a new way to speak about the actualities of world, not as substances or processes but a way that subsumes both. (shrink)

According to process ontology in the philosophy of biology, the living world is better understood as processes rather than as substantial individuals. Within this perspective, an organism does not consist of a hierarchy of structures like a machine, but rather a dynamic hierarchy of processes, dynamically maintained and stabilized at different time scales. With this respect, two processual approaches on enzymes by Stein (Hyle Int J Philos Chem 10(4):5–22, 2004, Process Stud 34:62–80, 2005, Found Chem 8:3–29, 2006) and by Guttinger (...) (Everything Flows: Towards a Processual Philosophy of Biology, Oxford University Press, Oxford, 2018) allows to think of macromolecules as relational and processual entities. In this work, I propose to extend their arguments to another case study within the biochemical domain, which is the case of ligand receptors and receptor-mediated biosignaling. The aim of this work is to analyze the case of G Protein-Coupled Receptors and biosignaling under the consideration of a processual ontology. I will defend that the processual ontology framework is adequate for the biochemical domain and that it allows accounting for the current biochemical knowledge related to the case study. (shrink)