I am a PhD candidate in Philosophy at the University of California, San Diego. Currently, I am completing my dissertation under the supervision of Nancy Cartwright and David Danks. Other committee members include Kerry McKenzie and Stephan Haggard (Political Science).

I primarily work on issues at the intersection of general philosophy of science, philosophy of social science, and metaphysics, with a focus on causation, explanation, and theoretical virtues. I also work in philosophy of AI and meta-philosophy.

I hold a BA and MA in Philosophy from Renmin University of China and a MA in Philosophy from Simon Fraser University. I have held visiting positions at Kyoto University (Spring 2024), the University of Cambridge (Fall 2024), and Durham University (Spring 2025).

My name is pronounced as Wei-Shin Tsai. I use he/him/his pronouns and speak Hokkien, Mandarin, and English. You are welcome to reach out to me via email.

Research

My research interests fall into two general categories. Most of my research concerns causation, with an equal focus on the more metaphysically oriented discussion on its essential features, as well as the diversity and complexity of causal relationships in scientific contexts. I examine specific kinds of causal relationships in science (esp. social sciences), both to uncover their distinct metaphysical and epistemological characteristics and to assess whether our “grand” theories of causation provide a plausible and informative foundation for understanding these particular causal relationships.

Another research focus of mine is theoretical virtues, within both the contexts of scientific theories and philosophical theories. Some theoretical virtues that I am currently investigating include simplicity and scope.

In my dissertation Middle-Range Theories of Causation, I integrate these two research interests by exploring how philosophical theories of causation with varying scopes provide distinct yet complementary ontological insights into causation. In particular, I put an emphasis on an approach to causal theorizing that I term “middle-range theorizing,” borrowing the concept from the sociologist Robert K. Merton. I argue that this approach most effectively addresses causal diversity observed in scientific practice.

In addition, I am interested in topics related to scientific explanation, causal inference, evidence-based policy, and AI ethics.

Peer-Reviewed Publications

Causation

Simpson’s Paradox Beyond Confounding (with Zili Dong and Shimin Zhao), European Journal for Philosophy of Science, 2024.

Abstract: Simpson’s paradox (SP) is a statistical phenomenon where the association between two variables reverses, disappears, or emerges, after conditioning on a third variable. It has been proposed (by, e.g., Judea Pearl) that SP should be analyzed using the framework of graphical causal models (i.e., causal DAGs) in which SP is diagnosed as a symptom of confounding bias. This paper contends that this confounding-based analysis cannot fully capture SP: there are cases of SP that cannot be explained away in terms of confounding. Previous works have argued that some cases of SP do not require causal analysis at all. Despite being a logically valid counterexample, we argue that this type of cases poses only a limited challenge to Pearl’s analysis of SP. In our view, a more powerful challenge to Pearl comes from cases of SP that do require causal analysis but can arise without confounding. We demonstrate with examples that accidental associations due to genetic drift, the use of inappropriate aggregate variables as causes, and interactions between units (i.e., inter-unit causation) can all give rise to SP of this type. The discussion is also extended to the amalgamation paradox (of which SP is a special form) which can occur due to the use of non-collapsible association measures, in the absence of confounding.

Metaphilosophy

Determinism as a Stance (In Chinese), Journal of Dialectics of Nature, (作为立场的决定论，《自然辩证法通讯》), Forthcoming.

Abstract: Determinism is typically understood as a philosophical proposition about the causal order of the world. However, both global determinism, the view that events in all domains are determined by antecedent events, and local determinism, the view that only events in certain domains are determined by antecedent events, face serious theoretical challenges. Rather than trying to address these challenges while preserving determinism as a proposition, one simpler yet more effective response for advocates of determinism is to deny that determinism is essentially a philosophical proposition about the causal order of the world. Van Fraassen argues that some philosophical positions, including empiricism, should be understood not as propositions aiming to describe objective facts, but as philosophical stances that agents can adopt. Re-examined from this perspective, determinism can be understood as a philosophical stance that agents can adopt. Specifically, it is an attitude in which one defaults to assuming the existence of a deterministic causal explanation for an event unless there are compelling reasons to reject this assumption, and actively seeks such an explanation when necessary.

Other Topics

Causal Exclusion and Causal Autonomism, Frontiers of Philosophy in China, 2018. (Invited contribution as the best student essay at the 3rd Beijing Analytic Philosophy Conference.)

Abstract: The causal exclusion problem is often considered as one of the major difficulties for which non-reductive physicalists have no easy solution to offer. Some non-reductive physicalists address this problem by arguing that mental properties are to some extent causally autonomous. If this is the case, then mental properties will not be causally excluded by their physical realizers because causation, in general, is a relation between properties of the same level. In this paper, I argue that the response from causal autonomy cannot be successful for two reasons. First, it does not offer a satisfactory explanation for how mental particulars can have causal efficacy in a non-reductive physicalist framework. Second, the causal considerations underpinning this response do not really support the conclusion that mental properties are causally autonomous.

Papers In Progress

• A pair of papers on theorizing about causation (under contract).
• A co-authored paper on how causal structures explain (under review).
• A paper on simplicity as an ultimate cognitive value for human scientists (in Chinese; under review).
• A paper on how generative AI models can empower research in experimental philosophy (in Chinese; under review).

Teaching

I taught Philosophy of Science in Summer 2025.

I am currently designing a course on Philosophy of Social Science.