Publications
Last updated: Spring 2023
​Kolmogorov Conditionalizers Can Be Dutch Booked (If and Only If They Are Evidentially Uncertain) (w/ Snow Zhang). Review of Symbolic Logic (2022).
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A vexing question in Bayesian epistemology is how an agent should update on evidence which she assigned zero prior credence. Some theorists have suggested that the agent should update by Kolmogorov conditionalization, a norm based on Kolmogorov's theory of regular conditional distributions. However, it turns out that in some situations, a Kolmogorov conditionalizer will plan to always assign a posterior credence of zero to the evidence she learns. Intuitively, such a plan is irrational and easily Dutch bookable. In this paper, we propose a revised norm, Kolmogorov-Blackwell conditionalization, which avoids this problem. We prove a Dutch book theorem and converse Dutch book theorem for this revised norm, and relate our results to Rescorla (2018).
Examining the Quantum Principal Principle. Studies in the History and Philosophy of Science (2021).
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Earman (2018) has recently argued that the Principal Principle, a principle of rationality connecting objective chance and credence, is a theorem of quantum probability theory. This paper begins by critiquing Earman's argument; while Earman shows a certain principle follows from appropriate 'quantum' analogues of probabilism and conditionalization, that principle does not correspond to the Principal Principle. I then offer a positive proposal for how to formulate the Principal Principle in this quantum setting. I show that, while it not a theorem, the principle is intuitively plausible, and admits several important applications, including to the learning of unknown quantum states. 
You Say You Want a Revolution: Two Notions of Probabilistic Independence. Philosophical Studies​ (2021).
Branden Fitelson and Alan Hájek have suggested that it is finally time for a "revolution" in which we jettison Kolmogorov's axiomatization of probability, and move to an alternative like Popper's. According to these authors, not only did Kolmogorov fail to give an adequate analysis of conditional probability, he also failed to give an adequate account of another central notion in probability theory: probabilistic independence. I defend Kolmogorov, with a focus on this independence charge. I show that Kolmogorov's sophisticated theory of conditional distributions -advocated by authors such as Kenny Easwaran, but often overlooked by philosophers - has the resources to define the notion of independence Fitelson and Hájek seek. I then argue that Kolmogorov's original definition of independence, once suitably reinterpreted as capturing a slight logical weakening of this new notion, is not so problematic after all. Indeed, rather than discarding Kolmogorov's definition, we should make room for two distinct notions of probabilistic independence, one stronger and one weaker, which play different theoretical roles.
The Borel-Kolmogorov Paradox Is Your Paradox Too (w/ Snow Zhang). Philosophy of Science (2021).
The Borel-Kolmogorov paradox is often presented as an obscure problem that only certain accounts of conditional probability must face. In this paper, we point out that the paradox arises in the physical sciences, for physical probability or chance. By carefully formulating the paradox in this setting, we show it is a puzzle for everyone, regardless of one's preferred conditional probability formalism. We propose a treatment which is inspired by the approach that scientists took when confronted with these cases. The treatment complements that of Rescorla (2015), who considers the paradox as it arises for subjective probability. As we point out, the setting of physical probability raises new challenges and demands a rather different approach.
Clarifying the New Problem for Quantum Mechanics: Reply to Vaidman. Foundations of Physics ​(2021).
I respond to Lev Vaidman's recent criticisms of my paper "A New Problem for Quantum Mechanics".
A New Problem for Quantum Mechanics. The British Journal for the Philosophy of Science (forthcoming).
I introduce a foundational problem for quantum mechanics, distinct from the standard measurement problem, which I call the control problem. The characteristic feature of this new problem is that it introduces considerations of state preparation on top of considerations of state determination and measurement. Like the measurement problem, it places a fundamental constraint on quantum theories. 
Jeffrey Meets Kolmogorov (w/ Snow Zhang). Journal of Philosophical Logic (2020).
We introduce an axiomatic foundation for conditional probability, the theory of extensions, which handles cases involving probability-zero events. We show how the theory is related to (and in some senses equivalent to) two others: (i) a generalization of Jeffrey conditionalization which accommodates infinite partitions, and (ii) Kolmogorov's theory of regular conditional distributions, with the further requirement (discussed by authors such as David Blackwell) that the conditional distribution is proper. The paper builds on results due to Diaconis and Zabell (1982) and Gyenis, Hofer-Szabo, and Redei (2017), among others.
Selected Works In Progress
[Redacted for review]
A paper on the epistemology of chance [Email me for a draft]
A paper on quantum updating and accuracy (w/ Jer Steeger) [Email me for a draft]