Abstract Quantum mechanics is notoriously difficult to interpret. What does the theory say our world is really like? And what is it to ‘interpret’ a theory in the first place? Here I argue that the goal of interpretation is intelligibility, a goal which has always accompanied basic scientific pursuits. Intelligibility aims to show how that the world – as a theory pictures it – can be made intuitively clear. Quantum mechanics seems incapable of supporting this feature of intelligibility. But there are distinct kinds of intelligibility. I identify three kinds: mundane, mathematical and metaphysical. Theories can meet the demands of intelligibility to a greater or lesser extent across all three kinds. Quantum theory grades very high in terms of mathematical intelligibility but very low on mundane intelligibility. This mismatch motivates the search for ‘interpretations’ of quantum mechanics. These are efforts to provide metaphysical intelligibility. Various examples are considered and I investigate David Bohm’s approach as a case of a radical metaphysics whose motivations are somewhat akin to those of Leibniz.
Abstract Quantum mechanics is notoriously difficult to interpret. What does the theory say our world is really like? And what is it to ‘interpret’ a theory in the first place? Here I argue that the goal of interpretation is intelligibility, a goal which has always accompanied basic scientific pursuits. Intelligibility aims to show how that the world – as a theory pictures it – can be made intuitively clear. Quantum mechanics seems incapable of supporting this feature of intelligibility. But there are distinct kinds of intelligibility. I identify three kinds: mundane, mathematical and metaphysical. Theories can meet the demands of intelligibility to a greater or lesser extent across all three kinds. Quantum theory grades very high in terms of mathematical intelligibility but very low on mundane intelligibility. This mismatch motivates the search for ‘interpretations’ of quantum mechanics. These are efforts to provide metaphysical intelligibility. Various examples are considered and I investigate David Bohm’s approach as a case of a radical metaphysics whose motivations are somewhat akin to those of Leibniz.
Although David Bohm's interpretation of quantum mechanics is sometimes thought to be a kind of regression towards classical thinking, it is in fact an extremely radical metaphysics of nature. The view goes far beyond the familiar but perennially peculiar non-locality and entanglement of quantum systems. In this paper, a philosophical exploration, I examine three core features of Bohm's metaphysical views, which have been both supported by features of quantum mechanics and integrated into a comprehensive system. These are the holistic nature of the world, the role of a unique kind of information as the ontological basis of the world, and the integration of mentality into this basis as an essential and irreducible aspect of it.
Abstract Metaphysicians should pay attention to quantum mechanics, but not because it provides definitive answers to many metaphysical questions. The theory itself is remarkably silent on the nature of the physical world, and the various interpretations of the theory on offer present conflicting ontological pictures. Rather, quantum mechanics is essential to the metaphysician because it reshapes standard metaphysical debates and opens up unforeseen new metaphysical possibilities. Even if quantum mechanics provides few clear answers, there are good reasons to think that any adequate understanding of the quantum world will result in a radical reshaping of our classical worldview in some way or other. Whatever the world is like at the atomic scale, it is almost certainly not the swarm of particles pushed around by forces that is often presupposed. This book guides readers through the theory of quantum mechanics and its implications for metaphysics in a clear and accessible way. The theory and its various interpretations are presented with a minimum of technicality. The consequences of these interpretations for metaphysical debates concerning realism, indeterminacy, causation, determinism, holism, and individuality (among other topics) are explored in detail, stressing the novel form that the debates take given the empirical facts in the quantum domain. While quantum mechanics may not deliver unconditional pronouncements on these issues, the range of possibilities consistent with our knowledge of the empirical world is relatively small—and each possibility is metaphysically revisionary in some way.
The persistent interpretation problem for quantum mechanics may indicate an unwillingness to consider unpalatable assumptions that could open the way toward progress. With this in mind, I focus on the work of David Bohm, whose earlier work has been more influential than that of his later. As I’ll discuss, I believe two assumptions play a strong role in explaining the disparity: 1) that theories in physics must be grounded in mathematical structure and 2) that consciousness must supervene on material processes. I’ll argue that the first assumption appears to lead us toward Everett’s many worlds interpretation, which suggests a red flag. I’ll also argue that the second assumption is suspect due to the persistent explanatory gap for consciousness. Later, I explore ways that Bohm’s later work holds some promise in providing a better fit with our world, both phenomenologically and empirically. Also, I’ll address the possible problem of realism.
Abstract The paper investigates David Bohm’s philosophy of science as a form of fallibilist realism that underpins his causal interpretation of quantum mechanics Bohm (Bohm 1952a, 1952b, 1984, 1985, 1988, 1989, 1990; Bohm and Hiley 1975, 1984, 1993). Bohm’s central aim is to establish the superiority of his interpretation over the standard Copenhagen framework, particularly in contrast to that of Niels Bohr. Whereas Bohr asserts that knowledge of quantum phenomena is restricted to the statistical outcomes of measurement, Bohm’s approach is distinctly realist in orientation. Responding to the challenges posed by Einstein and other physicists, Bohm relies on extra-empirical criteria such as determinism, objectivity and intelligibility. The paper develops what will be termed the methodology of intuitive intelligibility (II), consisting of four stages: (1) reformulation of the standard quantum equations, (2) physical interpretation of the mathematical symbols, (3) drawing analogies with classical laws, and (4) drawing analogies with common experience. It is argued that Bohm applies the (II) methodology consistently, with the notable exception of the ontological status of the wave function and quantum potential. In attempting to explain causal relations from a 3N-dimensional configuration space (where N is the number of particles) to familiar three-dimensional space through an appeal to ‘information’, Bohm arguably commits a category mistake. A proposed resolution—drawing on Bohm’s own holistic analogies—is supported by the recent multi-field interpretation (Romano Multi-field and Bohm’s theory. Synthese, 198(30), 10587–10609, 2021). The term fallibilist realism aptly characterizes Bohm’s stance in the philosophy of science: he repeatedly emphasizes that the causal interpretation is not intended as a final theory. Nevertheless, holism constitutes a substantive ontological commitment that he is unwilling to abandon.
Despite scholarly consensus on the empirical facts, ever since its inception in the 1920s there has been deep disagreement about how to interpret quantum theory. “To interpret a physical theory is to say what the world would be like, if the theory were true.” All scientific theories require interpretation, since strictly speaking what they describe are our experiences of the world rather than the world itself. Thus, whether we are trying to explain or merely describe the world, we are always engaged in inference. To make inferences we need a context for interpretation. For any given claim this context is provided locally by related theories, more broadly by disciplinary paradigms, and ultimately by worldview claims about the nature of reality. The challenge in interpreting scientific theories is to integrate them into this hierarchy of knowledge. Usually this is not too difficult. New theories often require adjustments to nearby theories, but in doing so we can rely on paradigms to make them cohere. More rarely paradigmatic assumptions are themselves challenged, but in that case scientists can fall back on their worldview to make sense of the needed changes. By implication, the most difficult interpretive problems arise when our worldview is called into question, which leaves us without any frame of reference on which to fall back. Quantum theory poses a worldview problem. Prior to the quantum revolution the classical worldview could not be tested scientifically and so it was essentially metaphysical. Even though it corresponded to our experience of material objects, we lacked proof that it adequately represented the deep structure of reality. By giving us access to that deep structure for the first time, quantum mechanics made it possible to do such a test, or “experimental metaphysics.” Unfortunately, the results seemed to contradict classical assumptions, at least on the sub-atomic level.
The article continues the debate about whether classical “pure” metaphysics can explain scientific theories or science can generate its own metaphysical concepts. Two camps have emerged in modern analytic philosophy. The “metaphysician” camp defends the metaphysics of science by arguing that the fundamental concepts of classical metaphysics can be enriched, illustrated, or justified by examples from scientific theories. The “philosophers of science” camp views this as yet another invasion of metaphysics into their scientific territory. They advocate a scientific or naturalized metaphysics that strictly corresponds to modern scientific theories. Since the concept of possible worlds is a key element of mainstream analytic metaphysics, proponents of the metaphysics of science find it natural to appeal to the many-worlds interpretation of quantum theory. In turn, proponents of naturalized metaphysics often use popular metaphysical systems to justify the many-worlds interpretation of quantum mechanics. I will argue that the interpretation originally proposed by H. Everett remains only one of the ontologies of quantum theory, and attempts by philosophers of science to build a metaphysical construct on its basis encounter serious difficulties.