The metaphysics of mechanisms: an ontic structural realist perspective

Abstract Existing metaphysical accounts of mechanisms commit to the existence of objects or entities posited in scientific theories, and thus fall within the category of maximal metaphysics. In this paper, I demonstrate the incompatibility of object-based metaphysics of mechanisms with the prevailing trend in the philosophy of physics by discussing the so-called bottoming-out problem. In response, I propose and flesh out a structuralist metaphysics of mechanisms based on Ontic Structural Realism (OSR), which is a kind of minimal metaphysics. I argue that the metaphysical underpinnings of mechanisms are structures, whose metaphysical nature is elaborated through comparison with existing metaphysical theories of mechanisms. After that, I address the concern of whether objects in mechanisms can be accommodated in my account by invoking existing metaphysical theories of objects in special science by structuralists, such as Ladyman, J., & Ross, D. (2007). Every Thing Must Go: Metaphysics Naturalized . Oxford University Press.)’s real pattern account, and suggesting a potential alignment between OSR and processual ontology. Finally, I demonstrate how my view can naturally serve as the metaphysics for Mechanism 2.0 and be applied to systems biology.