ABSTRACT This article surveys recent work on primitive ontology (PO) approaches to quantum mechanics, focusing on proposals that seek to integrate this approach with the metaphysics of causal powers. PO approaches aim to provide a clear metaphysical picture in which the world consists of local entities such as particles, matter density fields or flashes, and these entities compose macroscopic objects, such as scientists and their measuring devices. To account for the behaviour of these local entities, some PO theories invoke the metaphysics of powers. After motivating PO approaches and contrasting them with wave function realism, I consider the development of power‐based POs, contrasting them with both Humean POs and POs which invoke primitive laws. I explain how different power‐based frameworks address key quantum phenomena, and I survey some difficulties, including the Problem of Holism, of small worlds and of top‐down causation. Such challenges are best confronted, I suggest, by drawing on Aristotelian hylomorphism: If powers are grounded in forms that unify physical systems, then power‐based POs can accommodate holistic and context‐sensitive behaviour.
ABSTRACT This article surveys recent work on primitive ontology (PO) approaches to quantum mechanics, focusing on proposals that seek to integrate this approach with the metaphysics of causal powers. PO approaches aim to provide a clear metaphysical picture in which the world consists of local entities such as particles, matter density fields or flashes, and these entities compose macroscopic objects, such as scientists and their measuring devices. To account for the behaviour of these local entities, some PO theories invoke the metaphysics of powers. After motivating PO approaches and contrasting them with wave function realism, I consider the development of power‐based POs, contrasting them with both Humean POs and POs which invoke primitive laws. I explain how different power‐based frameworks address key quantum phenomena, and I survey some difficulties, including the Problem of Holism, of small worlds and of top‐down causation. Such challenges are best confronted, I suggest, by drawing on Aristotelian hylomorphism: If powers are grounded in forms that unify physical systems, then power‐based POs can accommodate holistic and context‐sensitive behaviour.
Abstract The primitive ontology approach to quantum mechanics seeks to account for quantum phenomena in terms of a distribution of matter in three-dimensional space (or four-dimensional spacetime) and a law of nature that describes its temporal development. This approach to explaining quantum phenomena is compatible with either a Humean or powerist account of laws. In this paper, I offer a powerist ontology in which the law is specified by Bohmian mechanics for a global configuration of particles. Unlike in other powerist ontologies, however, this law is not grounded in a structural power that is instantiated by the global configuration. Instead, I combine the primitive ontology approach with Aristotle’s doctrine of hylomorphism to create a new metaphysical model, in which the cosmos is a hylomorphic substance with an intrinsic power to choreograph the trajectories of the particles.
Abstract An Aristotelian philosophy of nature rejects the modern prejudice in favor of the microscopic, a rejection that is crucial if we are to penetrate the mysteries of the quantum world. I defend an Aristotelian model by drawing on both quantum chemistry and recent work on the measurement problem. By building on the work of Hans Primas, using the distinction between quantum and classical properties that emerges in quantum chemistry at the thermodynamic or continuum limit, I develop a new version of the Copenhagen interpretation, a version that is realist, holistic, and hylomorphic in character, allowing for the attribution of fundamental causal powers to human observers and their instruments. I conclude with a critique of non-hylomorphic theories of primitive ontology, including Bohmian mechanics, Everettianism, and GRW mass-density.
I combine the idea of a primitive ontology with the metaphysics of laws of nature. In so doing, I examine the theoretical entities that are postulated in Newtonian mechanics, classical electrodynamics, and the de Broglie–Bohm quantum theory. I argue that the existence of mass, forces, fields, and the wave-function depends on the status of laws. The three major theories on laws of nature I treat are Humeanism, dispositionalism, and primitivism about laws. I point out that properties are notoriously ignored in debates on primitive ontologies. In fact, I show that properties, both intrinsic and relational, aren’t needed in physics; therefore, I replace the primitive ontology with a primitive stuff ontology, whose elements have no properties. Recently, a debate has started on the ontological status of forces in classical mechanics; I criticize the major positions and present my own idea that focuses on the status of laws of nature. Another hot topic is the status of the wave-function. Here, I develop a new interpretation in the framework of Humeanism that crucially differs from that advocated by David Albert and Barry Loewer, in that our world is not an illusion of a reality in configuration space. In addition, I propose a hitherto unconsidered way in which the wave–function can be construed as a holistic disposition.
The article sets out a primitive ontology of the natural world in terms of primitive stuff—that is, stuff that has as such no physical properties at all—but that is not a bare substratum either, being individuated by metrical relations. We focus on quantum physics and employ identity-based Bohmian mechanics to illustrate this view, but point out that it applies all over physics. Properties then enter into the picture exclusively through the role that they play for the dynamics of the primitive stuff. We show that such properties can be local (classical mechanics), as well as holistic (quantum mechanics), and discuss two metaphysical options to conceive them, namely, Humeanism and modal realism in the guise of dispositionalism.
The article sets out a primitive ontology of the natural world in terms of primitive stuff—that is, stuff that has as such no physical properties at all—but that is not a bare substratum either, being individuated by metrical relations. We focus on quantum physics and employ identity-based Bohmian mechanics to illustrate this view, but point out that it applies all over physics. Properties then enter into the picture exclusively through the role that they play for the dynamics of the primitive stuff. We show that such properties can be local (classical mechanics), as well as holistic (quantum mechanics), and discuss two metaphysical options to conceive them, namely, Humeanism and modal realism in the guise of dispositionalism.
This thesis contributes to the development of a ‘neo-Aristotelian’ ontology of powers that accommodates quantum phenomena. It offers a number of philosophical objections to ‘Super-Humean’ metaphysics, and constructs a sequence of models that aim to improve upon it, using the metaphysical toolbox constructed in Part I. In Part II, I explore how quantum entanglement challenges the ‘classical’ conception of the world as consisting of particles (or fields) with intrinsic physical properties (Chapter 3). I consider the metaphysical model offered by Super-Humeanism, which accommodates entanglement by combining a ‘primitive ontology approach’ to quantum mechanics with ontic structural realism (Chapter 4). According to Super-Humeans, the world is made of matter points constituted by distance relations. I raise three objections to its structuralist conception of matter. I then propose an alternative semi-Humean model, ‘Bohmian power structuralism’, which overcomes these objections through an ontology of ‘power-atoms’ with multi-track causal powers (Chapter 5). But its Humean conception of laws can be challenged. A second model, ‘power monism’, enriches the primitive ontology to include a ‘cosmic power’ that transforms the power-atoms into a cosmic whole, and supports an Aristotelian-essentialist conception of laws (Chapter 6). This model overcomes the difficulties with power structuralism, but is susceptible to Hawthorne’s ‘extrinsicality’ argument, excluding consciousness from the physical world. In Part III, I consider the emergence of thermochemical properties within macroscopic (or mesoscopic) quantum systems. Metaphysical models that incorporate only finite degrees of freedom, like Super-Humeanism, cannot accommodate properties like temperature and chemical entropy, which are represented in physics in the ‘thermodynamic limit’ (Chapter 7). I offer an additional argument against adopting a reductionist approach based on Putnam’s ‘permutation argument’ (Chapter 8). Finally, I outline a third model, ‘power pluralism’, in which the world consists of: a substrate of ‘power-gunk’, and ‘substantial powers’ that elicit substances from the power-gunk (Chapter 9). In this model, quantum-entangled microscopic particles are potential parts of macroscopic (or mesoscopic) substances, which have intrinsic thermochemical properties.