Research
My primary research interest lies in investigating the metaphysical nature of concrete objects within the constraints of contemporary physics. I am also interested in time and modality.

Bundle Theory and Weak Discernibility
Universal-Bundle Theory is the view that every concrete particular is solely constituted by its universals. This theory is often criticized for not accommodating the possibility of symmetrical universes, such as one that contains two qualitatively identical spheres two meters from each other in otherwise empty space. One universal-bundle theoretic solution to this criticism holds that the fact that the spheres are weakly discernible in that they stand in the irreflexive and symmetric relation *being two meters from* is sufficient for the numerical diversity of the spheres. For this solution to be effective, however, it should be established that weak discernibility not only necessitates but also explains numerical diversity. In this paper, I attempt to support this solution by arguing that the fact that two concrete particulars have a certain distance between them does explain why they are non-identical.
(Published in Analytic Philosophy (forthcoming), Dissertation Chapter)


Towards a Relational Ontology for Relational Quantum Mechanics
In this essay, I ask which ontological framework is most suitable for Carlo Rovelli’s (1996) relational quantum mechanics (RQM), one of the most recently proposed interpretations of quantum mechanics. RQM suggests that the state of a physical system is inherently relative to the observer. While there have been several philosophical debates on RQM in recent years, its ontology has rarely been discussed in philosophical literature. I propose a relation-oriented ontology for RQM, arguing that an observer-independent representation of the physical world is possible even in RQM, if we describe physical events in terms of relations rather than states. As an analogy, consider velocity. At one level of description, we can regard velocity as a monadic property of an object taking different values relative to the observers. However, at another level of description, we can take velocity as an observer-independent relation between objects (ignoring Einsteinian relativity). In a similar manner, I argue that RQM admits of a non-relative relational representation of physical reality, which combines descriptions by different observers into a single consistent picture. I argue that this provides some evidence for a version of ontic structural realism, which I call cubist priority relationism, which takes relation-tropes as the sole fundamental furniture of physical reality.
(Dissertation Chapter)
Permutation Symmetry and Non-reflexive Trope Theory
Trope-bundle theory is the view that a material object is solely constituted by some 'particularized properties called tropes. While trope-bundle theorists disagree about the details, they agree (explicitly or implicitly) that tropes have individuality in the minimal sense that they can be the relata of the (non-)identity relation. Given that at least some quantum particles are material objects, trope-bundle theory would entail that some quantum particles are fully constituted by some tropes. I argue that this consequence is at odds with the notion that quantum particles lack individuality, which has been proposed by some of the pioneers of quantum mechanics, such as Hermann Weyl (1928) and Erwin Schrödinger (1951). For if tropes have individuality, and some quantum particles are fully constituted by tropes, it would seem that those particles “inherit” individuality from their constituent tropes. In view of this problem, I propose what I call non-reflexive trope theory, which is partly based on the non-reflexive approach to quantum non-individuality developed and explored by Steven French and Décio Krause (2006) and others. According to this non-reflexive trope theory, some tropes are not the kind of entities that stand in (non-) identity, which accounts for the alleged lack of individuality of the quantum particles that they are thought to constitute.
(Presented at Eastern APA 2022, Dissertation Chapter)


Relativity and Two Dynamic Theories of Time
A dynamic theory of time is a metaphysical view of time that takes some of our pre-theoretical intuitions––especially the intuition that there is a special moment called the present and time passes in that which time is present changes––seriously. In this paper, I present and (conditionally) advocate a rarely discussed dynamic theory of time, which I call A*-theory, according to which there exists a mind-independent present and time passes mind-independently, but only in a way that is relative to the four-dimensional worldline of each observer. More precisely, I argue that the present with respect to an observer can be identified with a simultaneous hyperplane hyperbolic orthogonal to the worldline of the observer at some privileged point on the worldline. Then the passage of time with respect to the same observer amounts to the fact that which events are present with respect to the observer changes. A*-theory is not an A-theory of time, since the latter, but not the former, endorses a non-relative present. A*-theory is also not a B-theory of time, for the former, but not the latter, holds that the present is not purely indexical, psychological, or phenomenological. I argue that A*-theory preserves our temporal intuitions––as an A-theory of time arguably does––while being naturally consistent with special relativity––as a B-theory of time is. In the second half of the paper, I defend A*-theory from various potential objections, including the one that questions whether there can be a coherent rate at which time passes if time passes at all.
(Earlier versions of the paper were presented at APA Central 2020, Central States Philosophical Association 2019, and other conferences.)
Is the Principle of Recombination Humean?
To secure the plenitude of his possible worlds, David
Lewis proposes a purportedly Humean principle of recombination, according to which anything can coexist with anything and anything can fail to coexist with anything. I argue that there is more work to be done to establish that this principle is genuinely Humean, since it leads to some peculiar necessities that appear to be brute. To avoid these consequences, one could consider some restrictions on the principle of recombination. However, I argue that the Humean should reject such restrictions as arbitrary.
(Published in The Journal for Philosophical Ideas (CHUL HAK SA SANG, Korean Citation Index) (2022))


The Problem of Evil in Mahayana Buddhism
It is often thought that there is no such thing as the problem of evil in Buddhism. However, we (Seungil Lee and Jinsub Song) argue that there is an analog of the problem of evil in Dasheng quixinlun, one of the central texts in Mahayana Buddhism. According to Dasheng quixinlun, suffering (duhkha) is a consequence of ignorance (avidya) acted upon one-mind (eka-citta) through one of two aspects of one-mind, called ‘birth and death (samsara). The text tells us little about the origin of ignorance. A real puzzle lies in birth and death, in virtue of which one-mind is thought to be susceptible to ignorance in the first place. One-mind is claimed to be the ground of nirvana. If so, however, why does it also contain birth and death as one of its intrinsic aspects? How can the ground of nirvana also be a (partial) source of suffering? Regarding this 'Buddhist problem of evil,' we consider two possible responses, neither of which we find satisfactory.
Presented at the Society of Asian and Comparative Philosophy, Central APA 2019 (co-authored with Junsub Song)