(ms.). A Carnapian Solution to the Puzzle of Extrinsic Justifications. For Sophia Arbeiter & Juliette Kennedy (Eds.), Outstanding Contributions to Logic: Penelope Maddy. Springer.

Set theorists commonly give extrinsic justifications for axioms, i.e., they present the fruitfulness of axioms with respect to certain mathematical goals as evidence for their truth. The puzzle of extrinsic justifications is the question of how the fruitfulness of an axiom can be evidence for its truth. In this paper, I first discuss some problems for Penelope Maddy's solution to the puzzle of extrinsic justifications. I then propose an alternative, Carnapian solution according to which the fruitfulness of an axiom can be evidence for its truth because there are analytic truths to the effect that sets are fruitful with respect to certain mathematical goals. I argue that the Carnapian solution is independently plausible, that it avoids the problems faced by Maddy's solution, and that it neatly aligns with Maddy's epistemological and metaphysical views concerning set theory, as well as with her methodological commitments.

(2020). Why Is the Universe of Sets Not a Set? Synthese 197, 575–597.

According to the iterative conception of sets, standardly formalized by ZFC, there is no set of all sets. But why is there no set of all sets? A simple-minded, though unpopular, “minimal” explanation for why there is no set of all sets is that the supposition that there is contradicts some axioms of ZFC. In this paper, I first explain the core complaint against the minimal explanation, and then argue against the two main alternative answers to the guiding question. I conclude the paper by outlining a close alternative to the minimal explanation, the conception-based explanation, that avoids the core complaint against the minimal explanation.

(2019). Truth in Journalism. In James E. Katz & Kate Mays (Eds.), Journalism and Truth in an Age of Social Media, 103–116. Oxford University Press.

In order to fulfill their role in society, professional journalists must deliver truths. But truth-telling is not the only requirement of the goal of journalism. What is more, some of the other requirements of journalism can make it difficult for journalists to deliver truths, and may even force them to depart from truth in certain ways. In this paper, I make the requirements of the goal of journalism explicit, and I explain how conflicts between them can arise. I then make some suggestions for balancing these requirements that could help journalists regain the trust of the public.

(2018). Leibniz's Formal Theory of Contingency (with Jeffrey McDonough). Logical Analysis and History of Philosophy 21, 17–43.

This essay argues that, with his much-maligned “infinite analysis” theory of contingency, Leibniz is onto something deep and important—a tangle of issues that wouldn’t be sorted out properly for centuries to come, and then only by some of the greatest minds of the twentieth century. The first section places Leibniz’s theory in its proper historical context and draws a distinction between Leibniz’s logical and meta-logical discoveries. The second section argues that Leibniz’s logical insights initially make his “infinite analysis” theory of contingency more rather than less perplexing. The last two sections argue that Leibniz’s meta-logical insights, however, point the way towards a better appreciation of (what we should regard as) his formal theory of contingency, and its correlative, his formal theory of necessity.

(2018). Formal Analyticity. Philosophical Studies 175(11), 2791–2811.

In this paper, I introduce and defend a notion of analyticity for formal languages. I first uncover a crucial flaw in Timothy Williamson’s famous argument template against analyticity, when it is applied to sentences of formal mathematical languages. Williamson’s argument targets the popular idea that a necessary condition for analyticity is that whoever understands an analytic sentence assents to it. Williamson argues that for any given candidate analytic sentence, there can be people who understand that sentence and yet who fail to assent to it. I argue that, on the most natural understanding of the notion of assent when it is applied to sentences of formal mathematical languages, Williamson’s argument fails. Formal analyticity is the notion of analyticity that is based on this natural understanding of assent. I go on to develop the notion of formal analyticity and defend the claim that there are formally analytic sentences and rules of inference. I conclude by showing the potential payoffs of recognizing formal analyticity.

(2016). Leibniz's Formal Theory of Contingency Developed (with Jeffrey McDonough). In Ute Beckmann, et al. (Eds.), Internationaler Leibniz-Kongress X Vorträge, Vol. 1, 451–466. Georg Olms Verlag.

This essay develops our meta-logical interpretation of Leibniz’s formal theory of contingency by taking up two additional issues not fully addressed in our earlier efforts. The first issue concerns the relationship between Leibniz’s formal theory of contingency and his views on species and essentialism. The second issue concerns the relationship between Leibniz’s formal theory of contingency and the modal status of the actual world.